Band 9, Heft 1

The process optimization of microwave assisted leaching of manganese from electrolytic manganese residue (EMR) was conducted. The Box-Behnken design (BBD) was utilized to determine the number of experiments as well as to assess the effect of the main leaching parameters, including the reaction temperature, reaction time, concentration of sulfuric acid and dosage of citric acid. A quadratic model was found to best fit the experimental data and was utilized to optimize the process parameters to maximize the percentage manganese recovery. 3-D response surface plots and contour plots were generated utilizing mathematical models to understand the effect of variables as well as to identify the optimal conditions. The optimum conditions of microwave assisted leaching were: temperature of 76°C, time of 55 min, H 2 SO 4 concentration of 0.76 mol·L -1 , dosage of citric acid of 3.51 mg/g. Under these conditions, the percentage manganese recovery higher than 90% could be achieved.

This study provides a complete evaluation of a sustainable zero-waste process for the recovery of added value biomaterials from the abundant shrimp shell biomass waste using natural deep eutectic solvents (NADES). The process parameters for the fractionation of α-chitin, minerals and protein was followed using on-line measurements. Furthermore, the quantitative analysis of isolated chitin, minerals and solvent waste streams were examined. The dominant fractionation mechanisms are explained through the analysis of the liquid and solid fractions. Four of the most promising, and commercially available, NADES consisting on mixtures of Choline Chloride-Lactic Acid (CCLA), Choline Chloride-Malonic Acid (CCMA), Choline Chloride-Urea (CCUR) and Choline Chloride-Citric Acid (CCCA), were tested. The highest chitin extraction yield obtained was < 90% using CCLA, leading to purity higher than 98%. Moreover, it is possible to recycle this particular NADES several times, while having no loss in the shrimp shell fractionation capability.

The kinetics of isothermal extraction of caffeine from guarana seed under the action of ultrasonic field with simultaneous cooling (UESC) was investigated. The isothermal kinetics curves were measured at temperatures range T = 17-58 ° C. Using the model-fitting method it was determined that the kinetics of caffeine extraction can be described by a theoretical Jander three-dimensional diffusional model. The values of the rate constant were calculated for different temperatures, as well as the kinetic parameters (activation energy ( E a ) and pre-exponential factor (ln A )). Based on the results obtained, it is concluded that the rate constants of caffeine extraction under UESC are about 2 times higher in comparison to the values obtained for the extraction in the conditions of conventional heating (CH). The activation energy of the caffeine extraction under the UESC EaUESC=19.4kJ⋅ mol− 1$\left( E_{\text{a}}\,^{\text{UESC}}=19.4\,\text{kJ}\cdot \text{mo}{{\text{l}}^{-1}} \right)$is lower than the values are for CH EaCH=21.8kJ⋅ mol− 1.$\left( E_{\text{a}}\,^{\text{CH}}=21.8\,\text{kJ}\cdot \text{mo}{{\text{l}}^{-1}} \right).$Energy consumption for UESC is four times lower than for CH conditions. It is shown that there is a linear correlation relationship between kinetic parameters obtained for UESC and CH conditions. The changes in the values of kinetic parameters are explained by the model of selective transfer of energy from the reaction system to the reactant molecules.

This study was conducted to fabricate scaffold from polylactic acid (PLA) and hydroxyapatite (HA) extracted from waste bovine bone for enhancing both mechanical and biocompatible properties. After pretreatment in dilute NaOH solution, the bone was calcined at 900°C for 6 h, ball milled and converted to HA. Factors that affect the formation of HA were investigated. Experimental results showed that HA particles with crystal size < 100 nm and 99% crystallinity could be obtained at 90°C, pH 11 and 35 mM H 3 PO 4 solution followed by 4 h calcination at 900°C. By using non-solvent induced phase separation method, PLA scaffolds with pore size and surface area of 22.6 μm and 25.7 m 2 /g, respectively, containing different hydroxyapatite were successfully prepared. Tensile strength of scaffolds increased due to effective support by HA grafted collagen. PLA scaffolds containing HA were more degradable than PLA scaffolds and PLA scaffolds containing HA grafted collagen. Cell culture results showed that cell density increased significantly on porous scaffolds than that on the dense scaffolds. Moreover, cell density also increased significantly on the scaffold containing HA grafted collagen than that on the scaffold with pure HA.

For green synthesis in organic phases, the catalysis of lipases needs to be further improved. Here a strategy is to simulate the activation of lipases at water/oil interface by immobilizing lipase on an available carrier material, which can replace the water at the interface to stabilize enzyme against denaturation from organic phase. The carrier is selected as cotton fiber on which Pseudomonas cepacia lipase is immobilized by physical adsorption in a column glass bottle to form a simple bioreactor together with the bottle. In synthesis of fragrance ester hexyl acetate via transesterification of hexanol with vinyl acetate, the bioreactor exhibits a 3-fold increase in the ability to transform substrate, relative to native lipase in terms of the initial period of reaction at 37°C and 160 rpm. And also the bioreactor is very stable in catalysis for that it has an extra long half life t 1/2 = 636 h, calculated from the decrease degree of molar conversions in six times of 6-hour transesterifications. More interestingly, the bioreactor behaves excellent activity at room temperature and in a static state, and can transform nearly 100% hexanol after 48 h. All these indicate that the bioreactor has great potential for industrial application.

In this work, we showed the synthesis of zinc oxide nanoparticles (ZnO NPs) using leaf extract of Punica granatum . Characterization results showed the synthesis of stable ZnO NPs with average size of 7 nm. Fourier transform infrared (FT-IR) and zeta potential results confirmed the capping of ZnO NPs with plant extract polyphenols. X-ray diffraction (XRD) and selected area electron diffraction (SAED) examinations showed the crystalline nature of prepared ZnO NPs. Further, the cytotoxic properties of the green synthesized ZnO NPs are examined against pediatric leukemia cells and the morphology of cells was studies under microscope. The results of cytotoxicity and microscopic images revealed the dose dependent cytotoxicity, indicating their prospects for the development of novel techniques and materials for pediatric leukemia cancer therapy.

Palladium is very expensive metal and has numerous applications especially as a versatile hydrogenation and dehydrogenation catalyst for chemical reactions. The main hurdle in its wide use is the high materials cost. In the present study a cost effective palladium nano catalyst was prepared using the green method of synthesis with guar gum as capping and reducing agent. The formations of palladium nanoparticles were confirmed by UV-spectrophotometer while for morphology and nature, SEM and XRD were performed that confirmed the crystalline nature of PdNPs and proved the roughly spherical shape of nanoparticles. FT-IR analysis showed different functional groups of reducing agent and proved that guar gum have the ability to stabilized as well as to reduce the Pd (II) to Pd (0). Specific signal for the palladium is present in EDX spectra that further confirmed the formation of PdNPs. The catalytic efficiency was studied using the hydrogenation of 4-nitrophenol. Rate constant of prepared nano-catalyst was 0.1436/min, its efficiency, TON, TOF, in above mention reaction is 90.83, 27.78, and 185.2/hrs, respectively. Data obtained proved synthesized PdNPs to be efficient heterogeneous catalyst for the reduction of 4-NP and for the degradation of azo dyes.

Biosurfactants are surface-active metabolites produced by microorganisms. Biosurfactants tend to solubilize hydrocarbons in the surrounding environment, by reducing surface tension and increasing carbon uptake. In this study, isolation of biosurfactant producing bacteria and effect of renewable, non-fossil fuel based carbon sources on production were assessed. Oil field produced water was collected from Potwar oil fields and thirteen strains were isolated. Strains were screened for biosurfactant production by hemolysis test, emulsification index test, emulsification assay, oil displacement test, drop collapse test, tilted glass slide test and oil coated agar emulsification test. Strains were further screened for maximum production on cost effective renewable carbon source e.g. glucose, waste glycerol and animal fat. Promising strains were identified as Bacillus subtilis (MH142143), Pseudomonas aeruginosa (MH142144), Bacillus tequilensis (MH142145) and Bacillus safensis (MH142146) by 16S rRNA gene sequencing. Among all isolates, highest biosurfactant production on glucose (37%), glycerol (48%) and animal fat oil (49%), after 24 h cultivation was by Pseudomonas aeruginosa . Biosurfactant showed similarity to rhamnolipids by Thin Layer Chromatography (TLC). Assessment of bioactive propertiaes of rhamnolipid showed strong antimicrobial activity against Bacillus spp. Future investigations can be focused on application of these strains in environmental as well as industrial sectors.

Currently, the green route for synthesis of silver nanoparticles (Ag NPs) using plants leaf extract is an emerging research area in nanotechnology. The present study was explored for synthesis, characterization and catalytic application of Ag NPs using Diospyros lotus fresh leaf extracts. Factors affecting the synthesis were optimized and optimum conditions were pH of 8.6, silver nitrate (AgNO 3 ) concentration of 1.5 mM and 10 mL leaf extract. Formation of Ag NPs was observed by change in color of reaction mixture from pale yellow to reddish brown. The synthesized Ag NPs were characterized using UV-Vis spectrophotometer, EDX, XRD and SEM analyses. UV-Vis spectrophotometer showed maximum absorbance peak in the range of 407 nm at different time intervals indicating formation of Ag NPs. SEM and XRD analysis confirmed face centered cubic structure and crystalline nature of biologically synthesized Ag NPs with average particle size of 27 nm. The purity of synthesized Ag NPs was revealed by EDX. Finally, photo catalytic activity (PCA) of Ag NPs was studied and 72.91% decolorization of industrial waste water was obtained at 54 h. Some important parameters like pH, turbidity, conductance; TSS, TDS, sulphide, sulphates, etc. were also monitored before and after treatment with Ag NPs.

The method of microwave strengthens roasting neutral leaching slag contained germanium is put forward. The dielectric properties and temperature rising behavior of neutral leaching slag in the microwave field are analyzed via experimental and theoretical analysis. The experiment used the dielectric constant test device, the microwave roasting device and the temperature measuring device. The neutral leaching slag can absorb microwave energy and transform into heat energy. The specific surface area of the calcined slag containing the neutral leaching slag is increased by microwave roasting, and the microwave energy can reduce the particle size of the mineral particles to some extent. At the same time, cracks can be seen on the surface of the calcined sand after microwave roasting. The surface of neutral leaching slag roasted by microwave reformed cracks which help to open reaction channels making the oxygen to inside takes part in oxidizing reaction significantly improving germanium oxide reaction conditions, besides increasing the leaching process of the reaction area and increasing the leaching rate. The research on the dielectric constants and temperature characteristics of neutral leaching residue can provide the theoretical and experimental basis for microwave strengthen roasting.

The Lysimachia foenumgraecum Hance extract (LHE) was used for silver nanoparticles (AgNPs) synthesis. In this study, the herbal plant of Lysimachia foenumgraecum Hance (LH) was extracted with deionized water and we are the first to successfully use LHE as reducing and stabilizing agents for the green synthesis of AgNPs. The concentration of LHE used in this study was in the range of 0.003 to 1.0 wt%. Aqueous colloidal solutions of AgNPs reduced and stabilized by LHE show long-term stability due to the steric stabilization effect. This can be confirmed by zeta potential measurements which afforded values approximately of 0 mV, indicating the steric stability of AgNPs colloidal solutions synthesized by LHE. Furthermore, the obtained AgNPs colloidal solutions show superior antibacterial effect to gram-positive bacteria ( Staphylococcus aureus ) comparing to Chloramphenicol (positive control). AgNPs with LHE 0.003 wt% affords the highest antibacterial effect to S. aureus showing an inhibition zone diameter of 19.08 ± 0.67 mm; which is superior to Chloramphenicol.

This paper aims to investigate the heating behaviors of Y-TZP arrays under microwave irradiation. In this study, a three-dimensional numerical model of the microwave heating system was developed by COMSOL Multiphysics software. The numerical model was verified by microwave heating experiment, and the average root means square errors (RMSE) between the simulation and experimental data also confirmed the reliability of the model. The varying position and arrays of materials were applied to predict and visualize the three-dimensional distribution of the electromagnetic field and temperature during the microwave heating process. The results show that the temperature field distribution in microwave cavity was highly sensitive to the dielectric materials, the arrangement of the Y-TZP array interfered with the distribution of standing waves. The results can serve as references for the study to design and optimize the ceramic’s application in terms of microwave heating.

Nickel salts of Keggin-type heteropolyacid on Zr(IV)-based metal-organic frameworks (UiO-66) has been synthesized via ion-exchange followed by a facile one-pot hydrothermal method. The synthesized catalysts underwent FT-IR, N 2 adsorption-desorption, powder XRD, SEM and TEM analysis. The NiHSiW/UiO-66 catalyst was used as a new and effective solid acid in the catalytic transfer free fatty acid to biodiesel with an optimum conversion of 86.7%. The excellent activity of the NiHSiW/UiO-66 nanocatalyst was closely related to its high specific surface area, nano-sized catalyst, and the synergistic effects of NiHSiW salts and UiO-66 matrix. Importantly, a relatively stable catalytic performance was achieved for 8 repeated cycles. Finally, kinetics of the esterification reaction have been assumed to be of pseudo first order.

A novel hydrogel slow-release nitrogen fertilizer based on sawdust with water absorbency was prepared using grafting copolymerization. Urea was incorporated as nitrogen source in a hydrogel fertilizer. Potassium persulfate (KPS) and N,N᾽-methylenebis acrylamide (MBA) were used as the initiator and cross-linker, respectively. The structure and properties of the samples were characterized by XPS, EDS, SEM, XRD and FTIR. The effects of various salt solutions, ionic strength and pH on swelling behavior were discussed. The results showed that the largest water absorbency of the sample reached 210 g/g in distilled water. In addition, the sample had the good nitrogen release property. Thus, the novel environmentally friendly hydrogel fertilizer may be widely applied to agricultural and horticultural fields.

ASP was used to synthesize FeNP A . They were characterized by UV-vis spectroscopy, FT-IR, TEM, SEM, XRD and ZP. The aim of this study was to evaluate in vitro cytotoxic activity and antioxidant acitivities of FeNP A and ASP . The antioxidant properties were evaluated using DPPH, ABTS + and H 2 O 2 assays. FeNP A had higher antioxidant activity comparing to ASP according to DPPH (IC 50 : 3.48 μg/mL) and ABTS + (60.52%) assays. Anti-cancer activities of FeNP A and ASP were investigated in breast cancer, melanoma and control cell lines. FeNP A was more cytotoxic than ASP in MCF-7, MeWo, CHL-1, and HEL 299 cells. FeNP A had shown that mitochondria induce apoptosis through stress in MDA-MB-231, and cells MeWo. ASP also induced apoptosis 2.23-fold in MCF-7 cells. Progesterone receptor gene expression showed a 10-fold increase in a hormone-dependent MCF-7 cell line in ASP , and FeNP A treatment. Expressions of BCL6, CXCL12, DNAJC15, RB1 and TPM1 in melanoma cancer cell lines were significantly increased in ASP and FeNP A administration. It had been shown that FeNP A regulates gene expressions that may be considered important in terms of prognosis in breast cancer and melanoma cell lines and it is suggested that gene expressions regulated by FeNP A are also evaluated in animal models in vivo.

Metal magnesium is mainly produced from the calcined dolomite by the silicothermic production. However, in this process, the reduction temperature is higher while the reaction speed is slow, which results in higher energy consumption and serious environmental problems. In this paper, adding aluminum into the ferrosilicon reducing agent is expected to lower the reaction temperature so as to solve the problems above. The phase transition involved in the whole reduction process including with and without aluminum addition were investigated in details by theoretical calculation and experimental research. The influence of aluminum on the magnesium oxide reduction path was analysis to clarify the internal mechanism. The results show that aluminum added into the ferrosilicon would first react with magnesium oxide to form magnesium vapor and alumina under vacuum pressure of 10 Pa when the temperature rises to 720°C. Then, calcium aluminate would be formed by the reaction of aluminum oxide and calcium oxide. Once the temperature reaches 1150°C, silicon begins to reduce the magnesium oxide to create the silicon oxide that will finally react with calcium oxide to form calcium silicate. When the temperature rises above 1150°C, both the aluminum and silicon will participate in the reduction of magnesium oxide. In the process of heating up, the mixture of aluminum, ferrosilicon and calcined dolomite forms Mg 2 Al 4 Si 5 O 18 and Ca 3 Al 2 (OH) 12 phase with the components in calcined dolomite. Mg 2 Al 4 Si 5 O 18 and Ca 3 Al 2 (OH) 12 phase finally form Ca 12 Al 14 O 33 phase. The interaction between aluminum and ferrosilicon in the mixture is less; the mixture of aluminum and ferrosilicon first forms Al 3 FeSi 2 phase, and finally has the trend of forming Al 4.5 FeSi phase. There is a great difference between the phase transformation of aluminum in the mixture of aluminum, ferrosilicon and calcined dolomite and that of aluminum in the mixture of aluminum and ferrosilicon.

Green synthesis is a simple, non-toxic, economical and eco-friendly approach for the synthesis of nanoparticles. In the present work, nanoparticles of titanium dioxide (TiO 2 NPs) were synthesized using an aqueous solution of Syzygium cumini leaf extract as a capping agent. These green synthesized TiO 2 NPs were further evaluated for photo catalytic removal of lead from industrial wastewater. Obtained nanoparticles were characterized using: high-resolution scanning electron microscopy (HRSEM), high-resolution transmission electron microscopy (HRTEM), X-ray energy dispersive spectroscopy (EDS), Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), dynamic light scattering (DLS) and Brunauer-Emmett-Teller (BET). Obtained results revealed that synthesized TiO 2 NPs possess spherical morphology with anatase phase with a large BET surface area of 105 m 2 /g. Photo catalytic studies of TiO 2 NPs for lead removal from explosive wastewater were performed in a self-designed reactor. Inductive coupled plasma spectroscopy (ICP) was used to determine the lead concentration. Obtained results witnessed 75.5% removal in chemical oxygen demand (COD) and 82.53% removal in lead (Pb 2+ ). This application of green TiO 2 NPs is being explored for the first time.

Jatropha curcas biodiesel was taken as the research object, studied the single and compound effects of oxidation degree and temperature on kinematic viscosity of biodiesel, and established a mathematical model. The results indicate that the kinematic viscosity of biodiesel decreases gradually with the increase of temperature, and the mathematical model affected by the single factor of temperature is η = e ( A + Bt + Ct 2) . The kinematic viscosity of biodiesel increases with the increase of oxidation time. The regression equation between kinematic viscosity and conductivity is established as follows: η = A + Bμ . It is found that the influence of temperature on the kinematic viscosity of biodiesel is much greater than that of oxidation, and the higher the temperature, the lower the influence of oxidation on the kinematic viscosity of biodiesel. Through the analysis of the influence weight of two factors and the change rate of kinematic viscosity, it is found that with the increase of temperature, the effect of conductivity on the change rate of kinematic viscosity of biodiesel is positive, but the influence decreases gradually. The relationship between kinematic viscosity, temperature and oxidation

To research the roles of rare earth minerals in denitrification via the NH 3 -SCR, a mixture was made by certain ratio of rare earth concentrates and rare earth tailings, then treated by microwave roasting, and acids and bases to form a denitrification catalyst. The mineral phase structure and surface morphology of the catalyst were characterized by XRD, BET, SEM and EDS. The surface properties of the catalyst were tested by TPD and XPS methods, and the denitrification activity of the catalyst was evaluated in a denitrification reactor. The results showed that the denitrification efficiency increased up to 82% with complete processing. XRD, BET, SEM, and EDS spectrum analysis stated that the treated minerals contained cerium oxides and Fe−Ce composite oxides. The surface of the modified minerals became rough and porous, the surface area increased, and the surface-active sites were exposed. The results of NH 3 -TPD and NO-TPD showed that the catalyst surface could gradually adsorb more NH 3 and NO after each step. XPS analysis indicated that there were more Ce 3+ , Fe 2+ , and lattice oxygen in rare earth minerals catalyst after each treatment step.

Antibiotics are the chemicals responsible for killing pathogenic bacteria but inappropriate and extensive use of antibiotics is hazardous causing adverse impact on human health. Excessive use of antibiotics has led to the development of multiple-drug resistant bacteria posing health hazards to mankind. The study of nanoparticles has revolutionized the problem solving concerns regarding fields of agriculture, chemistry and medicine. Nanoparticles are smaller than atomic nuclei offering more surface area and greater reactivity. Bacterial silver nanoparticles (AgNPs) were studied for their antibacterial potential. AgNPs from Bacillus subtilus show the highest antibacterial activity. Nanoparticles exhibiting antibacterial activity can be helpful to reduce the toxic impact of synthetic antibiotics. Present work deals with the green production of silver nanoparticles by exploiting indigenous bacteria. These AgNPs were characterized through Fourier transform infrared spectroscopic (FTIR) analysis, transmission electron microscopy (TEM) and UV spectroscopic analysis and were also evaluated for their antibacterial and antifungal potential. The data suggested the extracellular biosynthesis method to be very effective for the biosynthesis of AgNPs in some bacterial strains. Keeping in view the antibacterial potential of studied AgNPs, the present work suggests green production of nanoparticles which can be effectively utilized as environment friendly antibacterial and antifungal agents.

This study focusses on the synthesis of carboxymethyl guar gum (CMG) via monochloroacetic acid under alkaline conditions. The reaction conditions were also optimized during the course of experiment. Guar derivative with variable degree of substitution (DS) were prepared and were confirmed by Fourier transform infrared (FTIR) spectroscopy. The DS was determined quantitatively by titration method for each derivative. The synthesized guar gum derivatives, being the natural thickners, have been used in textile printing technology. Substituted guar gum has been proved environmental friendly thickener as compared to synthetic thickeners. Penetration properties, fixation ability, colour fastness, levelness and fabric handling was compared with alginate thickener (commercially available). Guar gum thickeners showed enhanced properties versus alginate thickener and can be used as an alternative to synthetic thickeners in view of its green, non-hazardous and economical derivatives. Guar gum is the outstanding natural thickener, stabilizer, gelling agent and could possibly be used in various industrial units including food, cosmetic, textile, oil fracturing and mining.

Mixed matrix membrane (MMM), formed by dispersing fillers in polymer matrix, has attracted researchers’ attention due to its outstanding performance compared to polymeric membrane. However, its widespread use is limited due to high cost of the commercial filler which leads to the studies on alternative low-cost fillers. Recent works have focused on utilizing agricultural wastes as potential fillers in fabricating MMM. A membrane with good permeability and selectivity was able to be prepared at low cost. The objective of this review article is to compile all the available information on the potential agricultural wastes as fillers in fabricating MMM for gas separation application. The gas permeation mechanisms through polymeric and MMM as well as the chemical and physical properties of the agricultural waste fillers were also reviewed. Additionally, the economic study and future direction of MMM development especially in gas separation field were discussed.

Green synthesized nanoparticles from plant extracts are being used in various biomedical applications, particularly because of their bactericidal and cytotoxic activities. In this study, silver nanoparticles (AgNPs) were successfully synthesized from the Rosmarinus officinalis aqueous leaf extract. Different spectroscopic and microscopic analyses such as ultraviolet-visible (UV-vis) spectroscopy, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy, and energy-dispersive X-ray spectroscopy were performed to verify the biosynthesized AgNPs in our sample. The formation of nanosilver particles was preliminarily confirmed by UV-vis spectroscopy at 400 nm. The presence of carboxylic or amide groups was confirmed by FTIR, for the reduction of the silver ion. Transmission electron microscopy confirmed a particle size of 12–22 nm. The prepared AgNPs showed good antibacterial activity against human pathogens and good cytotoxic activity against the human breast cancer cell line (MDA MB 231). The nanoparticles prepared from R. officinalis can be used for various biomedical applications.

Stabilization of zero-valent CuNi nanoparticles (NPs) supported on Cicer arietenum (CP) is reported here for the reduction and removal of persistent organic pollutants. The functional groups and interactions of NPs with the CP were determined by ATR-FTIR. The crystallinity, morphology, and the elemental composition of the samples were determined through powder XRD, FESEM, and EDS techniques, respectively. The XRD spectrum displayed a sharp crystalline peak at 43.9 for CuNi. The Cu and Ni zero-valent NPs displayed a peak at almost the same region, and thus, both the peaks are merged and appeared as a single peak. The chemical reduction/degradation of eight model pollutants, viz., 2-nitrophenol (ONP), 3-nitrophenol (MNP), 4-nitrophenol (PNP), 2,4-dinitrophenol (DNP), methyl orange (MO), congo red (CR), methylene blue (MB), and rhodamine B (RB) were carried out in the presence of NaBH 4 . The k app value of 0.1 mM 4NP was highest which was 1.8 × 10 −1 min −1 while the slowest rate was observed for CR and RB with k app 5.5 × 10 −3 and 5.4 × 10 −3 min −1 respectively. This article helps in the removal of toxic organic pollutants through green supported NPs.

The rubber peptizer 2,2′-dibenzoylaminodiphenyl disulfide is typically synthesized from C 7 H 5 NS, NaOH, H 2 SO 4 , and H 2 O 2 , but these reactants were replaced with C 6 H 4 ClNO 2 , C 2 H 6 O, Na 2 S, S, and N 2 H 4 ·H 2 O, and these raw materials effectively improved the synthesis yield, reduced the number of synthetic steps, and made the synthetic process greener. Although the catalyst is difficult to recover, it effectively avoids using ethanol as a volatile organic solvent. The Aspen Plus method was used to simulate the key processes in the synthesis in the experimental conditions as the boundary conditions. The simulation results show that the feed ratio of C 7 H 5 NS, H 2 O 2 , and C 7 H 5 ClO directly determines the yield of the reaction, and the equivalents of NaOH, H 2 SO 4 , and Na 2 CO 3 indirectly affect the yield of the reaction by changing the reaction environment and controlling the formation of byproducts. The temperature of the ring-opening reaction and the acylation reaction should be maintained within 110–120°C to maximize the yield. The oxidation reaction temperature also directly affects the reaction yield and should be kept below 40°C. The simulation results are consistent with practical industrial production conditions. Based on the developed green synthesis process and the optimal process parameters obtained from the simulation, the industrial-scale production of 10,000 tons of 2,2′-di benzoyl amino diphenyl disulfide was carried out. Compared with that of o -nitrochlorobenzene, the yield of 2,2′-dibenzoylaminodiphenyl disulfide increased from approximately 72% to more than 90%. Using this method instead of the original synthesis method avoids the use of o -nitrochlorobenzene, which is neurotoxic; Raney nickel as the metal catalyst, which is difficult to recycle with existing environmental protection technologies; and ethanol as the organic solvent, which is associated with environmental problems. The amine tail gas that is easily generated in the original synthesis method is not generated in this system, and the drying step is eliminated.

This study was focused to synthesize silver nanoparticles (AgNps) from the aqueous extract of Bistorta amplexicaule and to evaluate their antimicrobial, antifungal, and 4-nitrophenol (4-NP) degradation potential. The AgNps from B. amplexicaule were characterized by field emission scanning electron microscopy, energy dispersive X-ray spectrometry, X-ray diffraction, and X-ray photoelectron spectroscopy studies. The biological activity of the AgNps was checked against the three bacterial and two fungal strains. The inhibition activities of the synthesized nanoparticles on pathogenic bacteria and fungi were equally studied using the colony-forming unit method. The AgNps synthesized showed excellent bactericidal and fungicidal activities against pathogenic Escherichia coli , Staphylococcus aureus , methicillin-resistant Staphylococcus aureus (MRSA), Candida albicans , and Candida tropicalis . The removal of nitrophenols is one of the most demanding tasks, due to their injurious impact on the health of the living organisms. The AgNps showed superior performance compared with the pure plant extract. The AgNps also displayed efficient catalytic ability in reducing toxic 4-NP into harmless 4-aminophenol in the presence of NaBH 4 solution. Hence, the synthesized AgNps can be effectively used against bacterial and fungal infections and in the decontamination of 4-NP polluted water.

Among the various green synthesis methods for nanoparticle synthesis, the honey-mediated green synthesis of nanoparticles is a fast, safe, biocompatible, and cost-effective method. In the present work, we demonstrate the sunlight-induced honey-mediated synthesis of silver nanoparticles and report the effect of light intensity, its color, and exposure time on the formation of nanoparticles. The visual inspection followed by UV-Vis spectral studies was performed to confirm the formation of silver nanoparticles. The HRTEM measurement confirms the formation of polydispersed silver particles. We further report the excellent antimicrobial activity of the synthesized nanoparticles against various strains of bacteria, which is found to be comparable to that of the antibiotic drug of choice. Our study points to further research on the possibility of considering these green synthesized silver nanoparticles as an alternative to antibiotics.

The adsorption of l -α-glycerophosphocholine (GPC) by cation-exchange resin 001 × 7 was studied in a batch system. The adsorbent dosage, shaking speed, and adsorption temperature were investigated. An adsorption efficiency of more than 99.4% was obtained under optimal conditions. The kinetic data evaluated by the pseudo-second-order kinetic model fitted the experimental data better than those evaluated by the pseudo-first-order model. The rate constant k 2 increased when the temperature increased, indicating the adsorption was endothermic in nature. The Langmuir and Freundlich isotherm models were used to analyze the adsorption equilibrium data, and it was found that the experimental data well fitted the Langmuir isotherm model. The thermodynamic parameters, enthalpy change (Δ G 0 ), free energy change (Δ H 0 ), and entropy change (Δ S 0 ), were calculated. The value of Δ G 0 was found to be in the range of −5.09 to −14.20 kJ mol −1 , indicating that the adsorption was spontaneous and basically physisorption, and the positive values of Δ H 0 and Δ S 0 exhibited that the adsorption was endothermic and the randomness of the system increased during the adsorption.

Green synthesis of metallic nanoparticles (NPs) is acquiring considerable attention due to its environmental and economic superiorities over other methods. This study describes the practical synthesis of silver nanoparticles (AgNPs) through the reduction of silver nitrate solution using an algal source, Chlorella vulgaris , as the reducing as well as the stabilizing agent. The energy required for this synthesis was supplied by microwave radiation. The ultraviolet-visible spectroscopy exhibited a single peak related to the surface plasmon absorbance of AgNPs at 431 nm. The AgNPs with high stability (a zeta potential of −17 mV), hydrodynamic size distribution of 1–50 nm, and mostly spherical shape were obtained through a 10 min process. Fourier transform infrared spectroscopy analysis revealed that several functional groups, including carbonyl groups of C. vulgaris , play a significant role in the formation of functional NPs. Antibacterial features of the produced AgNPs were verified against those of Salmonella enterica subsp. enterica serovar typhimurium and Staphylococcus aureus , demonstrating a considerable growth inhibition at increasing concentrations of the NPs. As a result, the formed AgNPs can be used as a promising agent against bacterial diseases.

Graphene oxide hydrosol was added dropwise to the surface of chitosan (CS) to successfully obtain graphene oxide/chitosan composite (GC). The composite material was characterized by scanning electron microscopy and X-ray diffraction. The prepared adsorbent was used to simulate the static adsorption of copper, lead, and cadmium ions from 100 mL of 50 mg/L simulated wastewater samples. When the pH of the simulated wastewater is 6, initial dosage is 70 mg, adsorption time is 90 min, and temperature is 20°C; the adsorption capacities for copper, lead, and cadmium are 60.7, 48.7, and 32.3 mg/g, respectively. The adsorption and desorption cycle experiments show that the adsorption capacity of GC for copper ions can reach 86% of the initial adsorption capacity after ten cycles. The adsorption of lead ions on the composite conforms to the Freundlich adsorption isotherm model.

Metal nanoparticles (MNPs) and metal oxide nanoparticles (MONPs) are used in numerous fields. The new nano-based entities are being strongly generated and incorporated into everyday personal care products, cosmetics, medicines, drug delivery, and clothing to impact industrial and manufacturing sectors, which means that nanomaterials commercialization and nano-assisted device will continuously grow. They can be prepared by many methods such as green synthesis and the conventional chemical synthesis methods. Green synthesis includes infinite accession to produce MNPs and MONPs with demanding properties. The structure–function relationships between nanomaterials and key information for life cycle evaluation lead to the production of high execution nanoscale materials that are gentle and environmentally friendly. Majority of plants have features as sustainable and renewable suppliers compared with microbes and enzymes, as they have the ability to pick up almost 75% of the light energy and transform it into chemical energy, contain chemicals like antioxidants and sugars, and play fundamental roles in the manufacture of nanoparticles. Plants considered the main factory for the green synthesis of MNPs and MONPs, and until now, different plant species have been used to study this, but the determined conditions should be taken into consideration to execute this preparation. In this study, we focus on the biosynthesis procedures to synthesize MNPs and MONPs, including comparison between green synthesis and the classical chemistry methods as well as the several new orientation of green synthesis of nanoparticles from different plant parts, especially plant leaf extracts. Plants with reducing compounds is the preferred choice for the synthesis of noble metals – metal ions can be reduced to the corresponding metals in the absence of any other chemicals under microwave irradiation conditions using benign solvent, water. Noble metals such as gold (Au), silver (Ag), platinum (Pt), and palladium (Pd) and other metals such as copper (Cu) and nickel (Ni), which are characterized by their optical, electronic, mechanical, magnetic, and chemical properties, leading to different technological applications. Plants with numerous reducing agents are suitable candidates for the manufacture of noble MNPs. The main purpose of this research is to give a background on green nanotechnology prospective evolution, pertinent concerns appeared related to the green synthesis of metal and metal oxide from plant extracts, nanoparticle formation mechanism, and the importance of flavonoids, vitamin B 2 , ascorbic acid (vitamin C), and phenolic compounds in the MNP and MONP production. The traditional sorghum beers are produced in many countries in Africa, but diversity in the production process may depend on the geographic localization. These beers are very rich in calories; B-group vitamins including thiamine, folic acid, riboflavin, and nicotinic acid; and essential amino acids such as lysine. However, the Western beers are more attractive than the traditional sorghum beers. The traditional sorghum beers have poor hygienic quality, organoleptic variations, and shorter shelf life compared with the Western beers. Many research studies on traditional sorghum beers have been carried out and documented in several African countries, especially the microbiological and biochemical properties, the technologies used in the manufacture processes, and synthetic characteristics of African traditional sorghum beers (ikigage, merissa, doro, dolo, pito, amgba, and tchoukoutou). The excellent resources for the production of greener biomaterials are plants and considerable advances have been achieved in many fields such as biotechnology and gene transfer. The manufactured biological nanomaterials have a great application in the pharmaceutical industry such as novel pharmaceuticals preparation, drug delivery personification procedures, and production of functional nanodevices.

Water hyacinth (WH) is a noxious weed. Its rapid growth can clog waterways, causing widespread ecological and environmental threats as well as power generation and irrigation issues. In the present study, water hyacinth was utilized as a precursor to synthesize multiwall carbon nanotubes (MWCNTs) using a simple chemical vapor deposition method. FESEM-EDS revealed that the synthesized MWCNTs had noodle-like, dense, and rough surfaces. TEM confirmed that MWCNTs had a bamboo-like structure with the diameter of 30–40 nm, and the wall thickness of approximately 7 nm. The interlayer distance was found to be approximately 0.34 by XRD. Raman spectra displayed three major bands of MWCNTS: D-band at 1,340 cm −1 , G-band at 1,596 cm −1 , and (D + G)-band between 2,783 and 2,953 cm −1 . The ratio of the D-to-G band intensity was 0.94 ± 0.03, indicating that the synthesized MWCNTs had well degree of graphitization. Electrochemical measurement results of the prepared MWCNTs cathode for aluminum–air battery showed that MWCNTs exhibited higher energy capacity than commercial graphite. Collectively, this study shows that water hyacinth could be used effectively as a precursor for the production of MWCNTs, thus successfully converting the noxious weed into high value-added materials.

Phosphorus extraction from phosphorus rock was conducted by carbothermal reduction with silica and coke. The effects of reaction temperature, reaction time, coke excess coefficient, molar ratio of silicon–calcium, and phosphorus rock particle size on the phosphorus reduction rate were investigated by the response surface methodology (RSM). The central composite design (CCD) with five factors and five levels was used to explore the effects of variables’ interactions on the phosphorus reduction rate. The results showed that there are significant interactions between reaction time and temperature; reaction temperature and molar ratio of silicon–calcium; reaction temperature and phosphorus rock particle size; coke excess coefficient and molar ratio of silicon–calcium; and coke excess coefficient and phosphorus rock particle size. The optimum conditions in the experimental range are reaction time 92 min, reaction temperature 1340°C, coke excess coefficient 1.27, molar ratio of silicon–calcium 1.28, and phosphorus rock particle size 75–106 µm, which were derived from the quadratic statistic model. Under these conditions, the phosphorus reduction rate can reach 96.88%, which is close to the model prediction value 99.40%. The optimized carbothermal reduction conditions of phosphorus rock by the RSM are helpful to reduce the energy cost of thermal phosphoric acid process.

TiO 2 has many advantages, such as UV resistance, thermal stability, and antibacterial; the attention toward TiO 2 composite materials (TCMs) is rapidly increasing in the protection of stone culture relics. An innovative rod-shaped TCM was synthesized in this study. The structure and morphology of TCM were studied by X-ray diffraction and scanning electron microscopy. The acid resistance, weather resistance, hydrophilicity, and photocatalytic performance of TCM had been investigated. The experimental results indicated that TCM has good protection effects. The stone sample treated with TCM has stronger acid resistance and weather resistance, better hydrophilicity, and more excellent photocatalytic activity compared with the untreated stone. More importantly, the stone treated with TCM has better acid resistance and weather resistance than that treated with normal shaped TiO 2 materials of the previous study. This work describes an effective way to protect stone cultural relics.

The current work described the preparation of gold nanoparticles (AuNPs) using the plant extract of Impatiens balsamina followed by evaluating their wound-healing potential. The formed NPs were studied by performing UV-visible spectroscopy, Fourier transform infrared, transmission electron microscopy and X-ray diffraction. Further, both the thermal and excision wound models were used to understand the wound-healing ability of AuNPs. It is exhibited that at a concentration of 20 mg, the AuNPs exhibited substantial decrease in excision wound within 8 days. The obtained wound-healing results indicated that the AuNPs prepared from the leaf extract of I. balsamina exhibited active wound-healing potential when related to traditional drugs; hence, AuNPs could have future applications in the development of dressing materials in nursing care for wound healing after surgery.

Zinc oxide nanoparticles (ZnO NPs) were hydrothermally fabricated, using hydroalcoholic clove extract. GC-MS analysis demonstrated that Eugenol is the main bioactive compound of the prepared extract. Experiments were designed, based on the central composite design. The effects of different amounts of zinc nitrate (2–6 g) and clove extract (10–30 mL) were evaluated for antioxidant and bactericidal properties of the formed ZnO NPs using the response surface methodology. The attained results demonstrated that more desirable NPs with maximum antioxidant activity (85.23%) and bactericidal effect, against Escherichia coli and Staphylococcus aureus , as manifested in the diameter of formed clear zones of 11.12 and 12.11 mm, respectively, were resulted using 3.98 g of the zinc salt and 20.30 mL of the clove extract. Furthermore, XRD and SEM analysis results revealed that the fabricated ZnO NPs had a hexagonal shape with a particle size of 50 nm and could degrade 70% of methylene blue during UV radiation.

Platinum nanoparticles (Pt NPs) have attracted interest in catalysis and biomedical applications due to their unique structural, optical, and catalytic properties. However, the conventional synthesis of Pt NPs using the chemical and physical methods is constrained by the use of harmful and costly chemicals, intricate preparation requirement, and high energy utilization. Hence, this review emphasizes on the green synthesis of Pt NPs using plant extracts as an alternative approach due to its simplicity, convenience, inexpensiveness, easy scalability, low energy requirement, environmental friendliness, and minimum usage of hazardous materials and maximized efficiency of the synthesis process. The underlying complex processes that cover the green synthesis (biosynthesis) of Pt NPs were reviewed. This review affirms the effects of different critical parameters (pH, reaction temperature, reaction time, and biomass dosage) on the size and shape of the synthesized Pt NPs. For instance, the average particle size of Pt NPs was reported to decrease with increasing pH, reaction temperature, and concentration of plant extract.

Green synthesis of 3-(1-naphthyl), 4-methyl-3-(1-naphthyl) coumarins and 3-phenylcoumarins has been carried out in one step by reacting 2-hydroxybenzaldehydes and 2-hydroxyacetophenones with 1-naphthylacetic anhydride and phenylacetic anhydride, respectively, using dual-frequency ultrasonication, i.e. ultrasonic bath of 40 kHz and probe of 20 kHz. The compounds were obtained in very high yield (80–90%) and their structures were confirmed by infrared and nuclear magnetic resonance data.

A simple chemical route was adopted for the preparation of adsorbent to remove fluoride in the simulation solution. In this study, commercially activated carbon (CAC) was used as the raw material, HNO 3 (20 wt%), La(NO 3 ) 3 ·2H 2 O (0.05 mol/L), and Al(NO 3 ) 3 (0.10 mol/L) were employed as modification reagents to successfully prepare the CAC adsorbent loaded with the elements La and Al (La( iii )–Al( iii )–CAC). The modified adsorbent was characterized by scanning electron microscopy, energy-dispersive spectroscopy, and Fourier-transform infrared spectroscopy measurements. The effects of variables such as solution pH, adsorption time, initial concentrations, and volume of solution were investigated on adsorption efficiency by the response surface method (RSM). Under optimum conditions, specified as a pH value of 6, an adsorption time of 1.2 h, an initial concentration of 30 mg/L, a solution volume of 25 mL, and the value of R F can reach at 74.11%. From the RSM analysis, the pH value was a significant factor in the adsorption process and the order for these key factors was as follows: pH > adsorption time > solution volume. Meanwhile, there were interactions among these factors. Chemical modification had an important role in pore structure generation and functional group of adsorbent to improve the adsorption efficiency. The removal performance of adsorbent on simulation solution of fluoride also showed the feasibility of adsorbent to be applied in industrial purposes.

The adaptive nature of algae results in producing unique chemical components that are gaining attention due to their efficiency in many fields and abundance. In this study, we screened the phytochemicals from the brown alga Hydroclathrus clathratus and tested its ability to produce silver nanoparticles (AgNPs) extracellularly for the first time. Lastly, we investigated its biological activity against a variety of bacteria. The biosynthesized nanoparticles were characterized by UV-visible spectroscopy, Fourier-transform infrared spectroscopy, dynamic light scattering, transmission electron microscopy, and energy-dispersive spectroscopy. The biological efficacy of AgNPs was tested against eighteen different bacteria, including seven multidrug-resistant bacteria. Phytochemical screening of the alga revealed the presence of saturated and unsaturated fatty acids, sugars, carboxylic acid derivatives, triterpenoids, steroids, and other components. Formed AgNPs were stable and ranged in size between 7 and 83 nm and presented a variety of shapes. Acinetobacter baumannii , Staphylococcus aureus , Methicillin-resistant S. aureus (MRSA), and MDR A. baumannii were the most affected among the bacteria. The biofilm formation and development assay presented a noteworthy activity against MRSA, with an inhibition percentage of 99%. Acknowledging the future of nano-antibiotics encourages scientists to explore and enhance their potency, notably if they were obtained using green, rapid, and efficient methods.

One-pot green synthesis of silver nanoparticles (AgNPs) has attracted much attention due to its simplicity, high feasibility in scaling up production, abundantly renewable sources, and environmental friendliness. Herein, Ocimum tenuiflorum and Phyllanthus urinaria leaf extracts (OT-ext and P.uri.ext, respectively) were chosen as reacting agents with rich and poor saponins to fabricate two biogenic AgNPs and characterize them. OT-AgNPs were simply and successfully generated by OT-ext. Ultraviolet-visible spectra showed the peak centered at 434 nm, which confirmed the presence of AgNPs after an 8-h reaction. FT-IR showed the organic functional groups (OH, C═O, C═C, CH, and COC) capping the surface of OT-AgNPs, which agreed with energy-dispersive X-ray spectroscopy analysis exhibiting the composition containing C, O, and Ag. Transmission electron microscopy micrographs revealed that OT-AgNPs possess spherical morphology, with a size range of 5–61 nm, and the majority having a small size within that range. In comparison, P.uri.AgNPs formed by P.uri.ext had a size distribution in a similar range, but the P.uri.AgNP diameter shifted toward larger sizes. Further, OT-AgNPs and P.uri.AgNPs showed an effective antifungal ability against Fusarium oxysporum , Aspergillus niger , and Aspergillus flavus . Overall, it was found that the rich saponins in the extracts lead to the formation of smaller AgNPs, but all extract-mediated AgNPs with a size less than 100 nm can act as a fungicide for various applications.

Gallosilicate zeolite (Ga-Silicate-1) was synthesized and characterized by wet chemical analysis, Fourier transform infrared spectroscopy, X-ray diffraction, BET surface area analysis and 29 Si MAS NMR. The prepared Ga-Silicate-1, calcined in the temperature range from 350°C to 550°C, was tested as a catalyst for the synthesis of propylene carbonate (PC) from CO 2 and propylene oxide in a solvent-free reaction. The effects of various parameters, such as co-catalyst, reaction temperature, reaction time, and pressure of CO 2 , on the reaction were investigated. It has been found that increasing the calcination temperature from 500°C to 550°C decreased both the conversion and selectivity to PC from 63.7% to 20.6% and from 77.6% to 58.9%, respectively. Unlike conversion and selectivity, the surface area increased from 96.1 to 103.8 m 2 /g. This significant increase in surface area due to the degalliation of the zeolite, along with the decrease in conversion, clearly indicates the role of gallium in the production of PC. Under mild reaction conditions (75°C and P (CO 2 ) = 0.55 MPa), a conversion of 70.8% and a selectivity of 81.3% were obtained. Based on the obtained results, a mechanism for the synthesis of PC over the Ga-Silicate-1 catalyst was proposed.

In this study, we reported an easy, rapid, cost-effective and environmentally benign method for the fabrication of silver nanoparticles (Ag-NPs) using Olea ferruginea as reducing, capping and stabilizing agent. For this, an aqueous extract of leaf and bark of O. ferruginea was treated with 1 mM AgNO 3 , which reduces Ag ions to Ag-NPs by establishing reddish brown color. The synthesized Ag-NPs were spherical crystals, with a mean size of 23 and 17 nm for leaf- and bark-mediated Ag-NPs, respectively. Fourier transform infrared spectroscopy affirmed the role of leaf and bark extracts of O. ferruginea as reducing, capping and stabilizing agent. These biosynthesized Ag-NPs showed profound antibacterial activity against Gram-negative ( Pseudomonas aeruginosa and Escherichia coli ) and Gram-positive ( Streptococcus pneumonia and Staphylococcus aureus ) bacteria. The highest antibacterial activity was shown by bark Ag-NPs against S. aureus (14.00 mm), while leaf Ag-NPs showed higher activity against S. pneumonia (13.00 mm). Additionally, they produced effective antioxidant activity against 2,2-diphenyl-1-picrylhydrazyl (DPPH) as compared to plant extracts and positive control. It was observed that the bark-mediated Ag-NPs had higher percentage (90%) of scavenging potential than the leaf-mediated Ag-NPs (78%). The significance of the current study is the synthesis of eco-friendly, easy and cost-effective Ag-NPs as biomedical products.

In recent years, green synthesis of nanoparticles has been the cornerstone of development of nanotechnology and its applications, as it emphasizes on promoting environmental sustainability. The aim of the present study was to investigate the potential health benefits of the green-synthesized titanium nanoparticles (TiO 2 NPs). TiO 2 NPs were synthesized using titanium( iv ) isopropoxide and lupin bean extract. The synthesized particles were characterized to assess the average particle size by dynamic light scattering, and X-ray diffraction method was used to study the crystalline nature. The average particle size recorded was 9.227 nm with a polydispersity index (PDI) of 0.382. The morphology of the particles was assessed by scanning electron microscope and transmission electron microscopy which showed varied shapes of the nanoparticles, uniform spherical and crystallite rod shaped. Further, the cytotoxic efficacy of the nanoparticles was assessed against the breast cancer (MCF-7) cell line using 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromidefor (MTT) assay. The antibacterial activity of the nanoparticles was evaluated against clinical pathogens via the disc diffusion assay. The key findings showed that the TiO 2 NPs exhibited potent cytotoxicity against the MCF-7 cell line with an IC 50 of 41.1 µg. It also showed profound antibacterial activity. Thus, the synthesized nanoparticles could have potential biomedical applications owing to their therapeutic efficacy.

This study showed the fabrication of gold nanoparticles (AuNPs) utilizing Erythrina senegalensis leaf extract as an effective, low-cost and eco-friendly approach. The bioconstituents existing in the E. senegalensis leaf extract are accountable for reducing and stabilization of NPs. The produced AuNPs were studied by using transmission electron microscopy, X-ray diffraction, UV-visible (UV-Vis) spectroscopy, Fourier transform infrared spectroscopy and energy-dispersive X-ray spectroscopy. In addition, this study also showed that the prepared AuNPs exhibited very good antipneumonial activity against mycoplasmal pneumonia in the investigational animals, indicating their potential for the development of new therapeutic drugs for the lung injury treatments in in the future.

Selenium (Se) as a bioactive micronutrient could be augmented via transforming into nanoparticles (NPs), especially using biogenic protocols, for usage as an antimicrobial element. The reducing power of costus ( Saussurea costus ) root extract (SCE) was employed for phytosynthesis of Se-NPs through a simple and rapid protocol that included stirred mixing of 10 mM Na 2 SeO 3 with 1.0% SCE solution for 4 h. The phytosynthesized SCE/Se-NP composite was obtained with a mean diameter of 6.13 nm and a zeta potential of −42.8 mV. Infrared analyses revealed the involvement of many SCE phytogroups in Se-NP synthesis, whereas transmission microscopy displayed well distribution and spherical shapes of the phytosynthesized NPs. The antibacterial assessments against foodborne pathogens ( Escherichia coli , Salmonella typhimurium and Staphylococcus aureus ) revealed the superior powers of SCE/Se-NPs and the elevated potentialities of SCE and Se-NPs for inhibition of bacterial pathogens. The scanning micrographs indicated that SCE/Se-NPs were attached to bacterial cells and led to their complete lysis/explosion with exposure prolongation. The SCE/Se-NP composites are recommended for the effective control of foodborne bacterial pathogens, applying a simple and eco-friendly phytosynthesis protocol.

Effects of the temperature of chitosan (CS) solutions as well as the temperature of the chamber on an electrospinning process were investigated. CS with a low molecular weight was dissolved in the solvent of trifluoroacetic acid/dichloromethane (70/30 v/v) at a concentration of 80 mg/mL for electrospinning. Both CS solution and chamber temperatures strongly affected the morphology of electrospun CS nanofibers. At the solution temperature and chamber temperature of 32°C, uniform CS nanofibers with an average diameter of 200 nm could be obtained. Although the chamber temperature is generally regarded as an unimportant parameter in the electrospinning of polymers, the experimental results demonstrated its critical effect on the electrospinning of CS.

The electrochemical behavior of gold dissolution in the Cu 2+ –NH 3 –S 2 O 3 2− –EDTA solution has been investigated in detail by deriving and analyzing the Tafel polarization curve, as this method is currently widely implemented for the electrode corrosion analysis. The dissolution rate of gold in Cu 2+ –NH 3 –S 2 O 3 2− –EDTA solution was determined based on the Tafel polarization curves, and the effects of various compound compositions in a Cu 2+ –NH 3 –S 2 O 3 2− –EDTA mixture on the corrosion potential and corrosion current density were analyzed. The results showed that the corrosion potential and polarization resistance decreased, whereas the corrosion current density increased for certain concentrations of S 2 O 3 2− –NH 3 –Cu 2+ and EDTA, indicating that the dissolution rate of gold had changed. The reason for promoting the dissolution of gold is also discussed.

Synthesis of nanoparticles is a fast-growing area of interest in the current development in science and technology. Nanoparticles are also used in biomedical applications. Green synthesis of nanoparticles is an environmental friendly and cost-effective technique. Trillium govanianum Wall. Ex. Royle crude extract was used for the eco-friendly genesis of silver nanoparticles (AgNPs). Aromatic amines were the functional groups involved in the bio-fabrication and synthesis of the AgNPs. The production of AgNPs was established by the appearance of brown color. The manufactured AgNPs were characterized by UV-Vis spectrophotometer, X-ray diffractometer, and FTIR spectrophotometer. AgNPs were face-centered cubic in nature with an average size of 9.99 nm. The produced AgNPs (18 µL disc −1 ) showed substantial antibacterial (53.74, 52.75, 51.61, 43.00, 36.84, and 36.84%) and antifungal (54.05, 42.11, 41.10, 40.85, 30.55, and 29.73%) potential against the tested bacterial ( X. campestris , P. aeruginosa , S. aureus , E. coli , B. subtilis , and K. pneumoniae ) and fungal ( A. alternaria , Paecilomyces , C. albicans , Curvularia , A. niger , and Rhizopus ) strains, respectively.

The current research aimed to evaluate in vitro biological activities of green-synthesized silver nanoparticles using the Allium sativum clove extract. The stability of green-synthesized silver nanoparticles was evaluated via storage at 4°C, room temperature (37°C), and calcined at 300°C, 500°C, and 700°C. The antibacterial effect was evaluated using agar well, spread plate, biofilm reduction, and cell proliferation inhibition assays. The cytotoxic and antidiabetic effects were determined via brine shrimp lethality, protein kinase inhibition, and α-amylase inhibition assays. DPPH scavenging, iron-chelating, anticoagulant, and hemolytic effects were evaluated. The highest inhibition of Klebsiella pneumoniae was observed when freshly prepared, calcined (300°C), and stored nanoparticles (4°C and 37°C) were applied (9.66, 9.55, 7.33, and 6.65 mm) against freshly prepared and calcined at 700°C which showed the highest inhibition of Pseudomonas aeruginosa (8.55 and 7.66 mm). Cell viability assay, biofilm reduction assay, and spread plate method showed a significant antibacterial effect of freshly prepared silver nanoparticles. Freshly prepared and calcined nanoparticles at 300°C and 500°C possessed strong antioxidant and iron-chelating activity. Among all the synthesized silver nanoparticles, freshly prepared and calcined nanoparticles (300°C and 500°C) increases the prothrombin time. Silver nanoparticles possessed significant anticoagulant properties and less toxic at least concentration toward human RBCs. In brine shrimp lethality assay, freshly prepared nanoparticles showed a stronger toxic effect and caused high mortality of larvae. Protein kinase inhibition assay revealed that freshly prepared nanoparticles had the highest zone of inhibition (18.0 mm) at 50 µg/disc. Green-synthesized nanoparticles would be used as potential therapeutic agents to overcome both infectious and noninfectious diseases.

N -Hydroxyethyl-substituted 1,2,3,4-tetrahydroquinolines were synthesized by the reaction of 2-(phenylamino)ethanol with unsaturated ketone catalyzed by acidic ionic liquid N -methyl-2-pyrrolidonium dihydrogen phosphate [NMPH]H 2 PO 4 , obviating the need for toxic and expensive catalysts. The acidic ionic liquid not only showed superior performance over H 3 PO 4 but also was stable and could be reused at least five times with a slight loss of activity. It provided a straightforward and efficient protocol for the synthesis of 1,2,3,4-tetrahydroquinoline derivatives.

The effect of KMnO 4 on the combustion characteristics and kinetic behavior of semi-coke was studied by thermogravimetric analysis. When 6 wt% KMnO 4 was added, the ignition temperature of semi-coke was the lowest. The apparent activation energy of semi-coke with different addition amount of KMnO 4 was calculated by Coats–Redfern integration method, the apparent activation energy of semi-coke during combustion reaction first decreased and then increased with increase in KMnO 4 . When 6 wt% KMnO 4 is added, the apparent activation energy is minimal. The apparent activation energy of semi-coke with 2 wt% KMnO 4 added at different conversion rates was calculated using Flynn–Wall–Ozawa integration method. The results show that the apparent activation energy of semi-coke combustion decreases with the increase of conversion.

The bimetallic Zn/Co zeolitic imidazole frameworks (ZnCo-ZIFs) were successfully synthesized by a simple solvothermal method at room temperature. Silver elements were afterward doped onto the bimetallic frameworks to form Ag/ZnCo-ZIFs via a facile impregnation method in acetone solvent. The as-synthesized material was used as a heterogeneous catalyst for the removal reaction of Congo red (CR) and malachite green (MG) in the presence of hydrogen peroxide (H 2 O 2 ). Effects of catalyst dosage, H 2 O 2 concentration, initial concentration of the contaminants, reaction temperature, and reaction time were conducted in this work. The results showed that more than 94% and 98% removal of CR and MG were, respectively, achieved within 45 and 30 min. The presence of Ag also enhanced the removal efficiency of CR and MG. The main mechanism of removal reaction of the organic contaminants could be oxidation via hydroxyl radicals. Moreover, the catalytic activity of the material remained over 90% after four recycling cycles. Due to the efficient reactivity as well as high stability, Ag/ZnCo-ZIFs can be a potential heterogeneous catalyst to remove hazardous dyes from aqueous solution.

White-light emitting lanthanide( iii ) metal-organic coordination polymers (LMOCPs) were prepared via a green synthesis method performed in pure aqueous solution at room temperature without using toxic solvent and reagents. This kind of LMOCP, denoted as adenosine monophosphate (AMP)/Ln-CIP, was composed of Ln 3+ {Ln = Tb (1), Eu (2), and Gd (3)}, hydrosoluble biomolecule of AMP, and nonpoisonous antenna ligand of CIP (ciprofloxacin). The complex of Tb(1), Eu(2), and Gd(3) in AMP/Ln-CIP emits strong green, red, and blue light, respectively. With careful adjustment of the doping mole ratio of the three lanthanide ions {Ln = Tb:Eu:Gd = 0.1:0.9:99.0} in one framework, white light-emission can indeed be achieved. AMP/Ln-CIP is network-structural and amorphous by transmission electron microscope and X-ray diffraction analysis. The fluorescence lifetime and quantum yield of AMP/Ln-CIP are 4.36 ms and 36.5%, respectively.

The paper industry is an essential but energy-intensive economic sector. This study aims to propose an appropriate inventory method to first determine the GHG emission factor in the life cycle of paper products of Vietnam. The approach overcomes the limitations of the ISO 14067 method by including the environmental burdens from the paper mill’s processes. In 2018, the amount of GHG emitted from cradle to gate when producing a ton of carton box, writing paper, and tissue products (EFCO2eq{\text{EF}}_{{\text{CO}}_{\text{2eq}}}) was 1,366 kg CO 2eq , 1,224 kg CO 2eq , and 751 kg CO 2eq , respectively. High energy intensity is identified as the main reason that causes high life cycle analysis (LCA) GHG emission factors and virgin paper-based products often emit higher LCA GHG amounts than recycled paper-based products. To reduce the emission, the Vietnamese paper mills should increase the use of recycled paper and replace fossil fuels with environmentally friendly energy resources.

Many innovative technologies have been developed around the world to meet its energy demands using renewable and nonrenewable resources. Solar energy is one of the most important emerging renewable energy resources in recent times. This study aims to present the state-of-the-art of parabolic trough solar collector technology with a focus on different thermal performance analysis methods and components used in the fabrication of collector together with different construction materials and their properties. Further, its industrial applications (such as heating, cooling, or concentrating photovoltaics), solar energy conversion processes, and technological advancements in these areas are discussed. Guidelines on commercial software tools used for performance analysis of parabolic trough collectors, and international standards related to performance analysis, quality of materials, and durability of parabolic trough collectors are compiled. Finally, a market overview is presented to show the importance and feasibility of this technology. We believe the compilation of reviews related to the above aspects will further provide impetus for the development of this technology in the near future.

A method was developed for rapid qualitative determination of lignocellulose in the tobacco cell wall by utilizing 2D heteronuclear single quantum coherence NMR spectra (2D HSQC NMR). Traditional methods for analyzing the structure of lignocellulose involve many steps of separation and extraction, which is labor-intensive. In this work, the whole cell wall was milled and dissolved in deuterium solvent. The solvent dimethylsulfoxide (DMSO-d 6 ) containing hexamethylphosphoramide (HMPA-d 18 ) enhanced swelling of the sample and gave high-resolution spectra. The tobacco samples are ball milled at different ball milling times, and the state of the particles is observed through an electron microscope, and then the probability of the particles being less than 5 µm is counted. Through the comparison of the abundance and integration of the peak signals in the spectra under different transmittances, it was determined that when the milling time was 6 h, the quality of the NMR spectra was the best. The optimum conditions of characterizing tobacco structure were DMSO-d 6 /HMPA-d 18 solution and 6 h milling time. Under these conditions, complete representation of the structure of lignocellulose and simplified process could be achieved. Graphical abstract

A converter slagging agent was prepared using converter precipitator dust and oxide scale as raw materials and bentonite, calcium oxide, and soluble glass as binders. The influence of different binders on the strength of the converter slagging agent was studied. The optimum ratio of bentonite, calcium oxide, and sodium silicate was determined by orthogonal experiments. The chemical composition, strength, moisture content, alkalinity, and other indicators of the prepared converter slagging agent met the requirements for converter smelting. The drop intensity of the green pellet was 3.7 times, and the compressive strength of the dry pellet could reach 988.72 N/m 2 . Therefore, the sustainable utilization of converter precipitator dust and oxide scale could be realized by the preparation of a converter slagging agent.

Mosquito-borne diseases are causing serious damage to public health worldwide, and control of these deadly mosquito vectors is a major thrust area for epidemiologists and public health workers. Therefore, the present research reports an eco-friendly solution with multipotency of silver nanoparticle fabricated from shrimp shell biowaste in controlling mosquitoes and bacterial pathogens. The biofabricated chitosan silver nanoparticles (Cs-AgNPs) were confirmed by UV-visible spectroscopy, transmission electron microscopy (TEM), Fourier transform infrared spectroscopy, energy dispersive X-ray spectroscopy, X-ray powder diffraction and zeta potential analysis. The TEM studies showed that the obtained Cs-AgNPs were mostly spherical in shape. Low doses of chitosan and Cs-AgNPs showed high mosquitocidal properties against both larvae and adult of Anopheles stephensi , Aedes aegypti , and Culex quinquefasciatus. The LC 50 (lethal concentration 50%) of Cs-AgNPs was 10.240 ppm (fourth instar larvae) and 9.671 ppm (adult) for An. stephensi ; 11.349 ppm (fourth instar) and 12.015 ppm (adult) for Ae. aegypti and 12.426 ppm (fourth instar) and 12.965 ppm (adult) for Cx. quinquefasciatus. The concerning part of antibacterial studies showed that Cs-AgNP had significant inhibition on tested bacterial pathogens. Overall, this study shows that chitosan extracted from the shrimp shell wastes can be used as a potential source for controlling major mosquito vectors.

Selenium nanoparticles (Se NPs) were fabricated with propolis hydro-alcoholic extract and six different methods, namely, hydrothermal, microwave irradiation, ultrasonication, UV radiation, self-assembling, and conventional heating. Results indicated that antioxidant activity, turbidity, pH, and brix values of the provided hydroalcoholic propolis extract were 85.8%, 2.235% a.u., 4.1, and 3.2°Bx, respectively. Gas chromatography analysis revealed that approximately 38 bioactive compounds were detected in the provided extract within 40 min of retention time, including chalcone. Results also revealed that each method had advantage in fabrication of Se NPs compared to others, but spherical Se NPs with overall appropriate physicochemical attributes of particle size (50–60 nm), polydispersity index (0.362), zeta potential (−41.8 mV), maximum broad absorption peak (321 nm), and antioxidant activity (12.4%) were synthesized using the ultrasonication method with a frequency of 20 kHz and a power of 300 W for 10 min.

The current study was conducted to assess the potential of ginger rhizome extract ( Zingiber officinale ) for the synthesis of silver nanoparticles (AgNPs) through the green method and its mitigating activity against pathogenic bacterial strains. AgNPs were synthesized through a simple one-step approach and characterized by UV-Visible (UV-Vis) spectroscopy, powder X-ray diffraction (PXRD), transmission electronic microscopy (TEM), and energy dispersive X-rays spectroscopy (EDS). PXRD and TEM results of AgNPs showed the face central cubic structures and predominantly spherical structures with a size of 6.5 nm. EDS analysis confirms the elemental silver in nanoparticles. Moreover, the impact of the pH, as well as temperature, during the synthesis of AgNPs has also been investigated. At 25°C and pH 5, there was no significant peak for AgNPs in the absorption spectra. However, with an increase in temperature from 25°C to 85°C and pH 5 to pH 11, particles started attaining the spherical shape of different sizes due to an increase in the reduction rate. The AgNPs displayed effective results against selected pathogenic strains, Pseudomonas aeruginosa (MTCC 424), Methicillin-resistant Staphylococcus aureus (ATCC 43300), and fungus Candida albicans (KACC 30003). The prepared AgNPs exhibited excellent antioxidant activity and catalytic reduction of methyl orange with the pseudo-first-order rate constant of 3.9 × 10 −3 .

The present study was aimed to biosynthesize selenium nanoparticles (SeNPs) and assess their foliar applications to improve the growth of wheat plants under controlled irrigation and drought stress. Bud aqueous extract of Allium sativum L. was used as a reducing and stabilizing agent of SeNPs followed by their optical and morphological characterization by using ultraviolet-visible spectroscopy, scanning electron microscopy, Fourier-transform infrared, and energy dispersive X-ray analysis. Various concentrations of SeNPs (10, 20, 30, and 40 mg/L) were applied exogenously to drought-tolerant (V1) and drought-susceptible (V2) wheat varieties at the trifoliate stage. Under the positive control conditions, plants were irrigated with 450 mL of water/pot (100% field capacity); and under water-deficit environment, plants were irrigated with 160 mL of water/pot (35% field capacity). Remarkable increase in plant height, shoot length, shoot fresh weight, shoot dry weight, root length, root fresh weight, root dry weight, leaf area, leaf number, and leaf length has been observed when 30 mg/L concentration of SeNPs was used. However, the plant morphological parameters decreased gradually at higher concentrations (40 mg/L) in both selected wheat varieties. Therefore, 30 mg/L concentration of SeNPs was found most preferable to enhance the growth of selected wheat varieties under normal and water-deficient conditions.

The present study explores the potential of Valeriana jatamansi shoot extract for Ag-metal bio-reduction and its antimicrobial activity. Among the different ratios of AgNO 3 and extract tested, 1:5 (1 mL AgNO 3 and 5 mL extract) gave maximum SPR peak at 411.0 nm during UV-Vis spectrophotometric analysis, indicating the synthesis of maximum amount of AgNPs in solution. XRD analysis reported the crystalline nature of AgNPs with 13.32 nm nanocrystallite size. FTIR studies suggested the involvement of carboxylic acid (–[C–O–O–H]) and methane (–CH–) functional groups of different compounds in AgNPs reduction and fabrication. Average size of synthesized uniform shaped nanospheres was 32 nm by SEM image analysis. The produced AgNPs (1.5 mg/disc) showed growth inhibition of 71.46, 65.97, 61.5, 55.32, and 54.83% against Pseudomonas aeruginosa , Escherichia coli , Candida albicans , Xanthomonas campestris , and Staphylococcus aureus . While the least growth inhibition of 48.55% was recorded for Klebsiella pneumonia , suggesting it as the least-susceptible microbe among all the tested microbial species. P. aeruginos a was found to be most sensitive of all tested microbes, while E. coli , C. albicans , and X. campestris reported moderate susceptibility to AgNPs.

The present study reports the synthesis of ZnO-NPs using Acantholimon serotinum extracts followed by characterization and evaluation of biological activities. Field emission scanning electron microscope revealed irregular spherical morphology with a size in the range of 20–80 nm. The X-ray diffraction analysis confirmed the synthesis of highly pure ZnO NPs with a hexagonal shape and a crystalline size of 16.3 nm. The UV-Vis spectroscopy indicates the synthesis of ZnO-NPs. FT-IR confirmed the presence of phytocomponents in the plant extract, which was responsible for nanoparticle synthesis. According to MTT results, the biosynthesized ZnO-NPs showed cytotoxic effects on human colon cancer Caco-2 (IC 50 : 61 µg/mL), neuroblastoma SH-SY5Y (IC 50 : 42 µg/mL), breast cancer MDA-MB-231 (IC 50 : 24 µg/mL), and embryonic kidney HEK-293 (IC 50 : 60 µg/mL) cell lines. Significant reactive oxygen species (ROS) generation was measured by the DCFH-DA assay after 24 h incubation with ZnO-NPs (200 µg/mL). ZnO-NPs caused apoptotic and necrotic effects on cells, which was confirmed by Annexin V-PE/7-AAD staining and 6.8-fold increase in pro-apoptosis gene Bax and 178-fold decrease in anti-apoptosis gene Bcl-2. The well diffusion method did not show effective growth inhibition activities of the ZnO-NPs against bacteria. In conclusion, the ZnO-NPs induce cytotoxicity in cell lines through ROS generation and oxidative stress.

Bayan Obo tailings are rich in rare earth elements (REEs), iron, and other catalytic active substances. In this study, mine tailings were calcined at different temperatures and tested for the catalytic combustion of low-concentration methane. Upon calcination at 600°C, high catalytic activity was revealed, with 50% CH 4 conversion at 587°C (space velocity of 12,000 mL/g h). The physicochemical properties of catalysts were characterized using thermogravimetric analysis, X-ray diffraction, scanning electron microscopy, hydrogen temperature-programmed reduction (H 2 -TPR), and X-ray photoelectron spectroscopy (XPS). Compared to the raw ore sample, the diffraction peak intensity of Fe 2 O 3 increased post calcination, whereas that of CeCO 3 F decreased. A porous structure appeared after the catalyst was calcined at 600°C. Additionally, Fe, Ce, Ti, and other metal elements were more highly dispersed on the catalyst surface. H 2 -TPR results revealed a broadening of the reduction temperature range for the catalyst calcined at 600°C and an increase in the reduction peak. XPS analysis indicated the presence of Ce in the form of Ce 3+ and Ce 4+ oxidation states and the coexistence of Fe in the form of Fe 2+ and Fe 3+ . Moreover, XPS revealed a higher surface O ads /O latt ratio. This study provides evidence for the green reuse of Bayan Obo mine tailings in secondary resources.

Preparation of inclusion complex using cyclodextrins is a well-known formulation strategy to elevate the solubility of drugs. However, often cyclodextrins alone may not bring a considerable improvement in the solubility of low solubility drugs. In this study, the inclusion complexation of furosemide (FSM) was tried with β-cyclodextrin (β-CD) either with the use or without the use of sodium lauryl sulfate (SLS), which is a surfactant. By using the kneading method, the binary complex of FSM/β-CD in the equal molar ratio was used. FSM and β-CD were kneaded continuously until a thick past was achieved, which was evaporated for a period of about 24 h. The solid complexed product was then crushed and stored in airtight container until use. Phase solubility studies confirmed a stoichiometric ratio of 1:1 (FSM/β-CD and FSM/β-CD with SLS). The apparent stability constant and complexation efficiencies of significantly enhanced in the presence of SLS. The prepared complexes were evaluated for DSC, PXRD, 1 H NMR, and in vitro release studies. The results exhibited a significant enhancement in diuresis in rats. It is evident that the addition of SLS with β-CD significantly enhances the solubilizing efficiencies and hence bioavailability of FSM.

The radical proliferation of pathogenic bacteria and their infections causes significant issues for human health and the environment. Today, biopolymers are used to produce different nanoparticles. In the present investigation, the fabricated chitosan/agar-silver nanoparticles (Cht/Ar-AgNPs)-coated papers were tested for antibacterial applications. Agar was used as a reducing agent for the synthesis of AgNPs. Synthesized Ar-AgNPs were examined through optical, phase crystallinity and topological analysis. Cht and Ar-AgNPs solution was mixed with various ratios of 9:1, 8:2, 7:3, 6:4, and 5:5 by weight. In addition to that, the conformity of Cht/Ar-AgNPs-coated papers was characterized by structural, spectral, and morphological analysis. However, Cht/Ar-AgNPs-coated papers were subjected to antibacterial properties. The ratio of (6:4) Cht/Ar-AgNPs-coated paper showed excellent antibacterial agent, and it can be used as extending the food product shelf life.

Palladium–nickel (Pd–Ni) bimetallic nano-catalysts supported on activated carbon (Pd–Ni/AC) have been successfully prepared by impregnation method enhanced with ultrasonic. The prepared Pd–Ni/AC catalysts were used for the catalytic hydrodechlorination reaction of bleached shellac and characterized by Fourier-transform infrared spectroscopy, nitrogen adsorption, X-ray diffraction, X-ray photoelectron spectroscopy, field-emission scanning electron microscope, and high-resolution transmission electron microscopy. The results show that Pd–Ni bimetallic structures in catalytic particles with the diameter of 4 and 14 nm were distributed uniformly on AC support, and the lattice fringe spacing in catalytic particles was measured as 0.213 nm which is lying in the region between monometallic Pd (111; 0.225 nm) and Ni (111; 0.203 nm), and that Pd 1 –Ni 1 /AC catalyst exhibits the best catalytic hydrodechlorination performance with the dechlorination efficiency of 92.58 wt% while it is used for the hydrodechlorination of bleached shellac, and the optimum catalytic performance is related to the synergistic electronic effect and bimetallic structure of the Pd 1 –Ni 1 /AC sample.

A novel porous ceramsite was made of municipal sludge, coal fly ash, and river sediment by sintering process, and the performance of batch and fixed-bed column systems containing this material in the removal of acid red G (ARG) dye from aqueous solutions was assessed in this study. The results of orthogonal test showed that sintering temperature was the most important determinant in the preparation of porous ceramsite, and it possesses developed pore structure and high specific surface area. Batch experiment results indicated that the adsorption process of ARG dye toward porous ceramsite was a spontaneous exothermic reaction, which could be better described with Freundlich–Langmuir isotherm model ( R 2 > 0.992) and basically followed the pseudo-first-order kinetic equation ( R 2 > 0.993). Column experiment results showed that when the porous ceramsite was used as packing material, its adsorption capacity was roughly improved by 3.5 times compared with that in batch system, and the breakthrough behavior was simulated well with Yoon–Nelson model, with R 2 > 0.954. This study suggested that the novelty man-made porous ceramsite obtained from solid wastes might be processed as a certain cost-effective treatment material fit for the dye removal in aqueous solutions.

Graphene is considered a promising catalyst candidate due to its 2D nature, single-atom thickness, zero bandgap and very high surface to volume ratio. Further, graphene oxide (GO) has been used as a catalytic support material for metal/metal oxide nanoparticles due to its tunable electrical properties. In addition, its high chemical stability and ultrahigh thermal conductivity may possibly promote high loading of catalytically active sites. This review article focuses on the recent progress in the catalytic applications of GO especially (i) as catalytic-support material (GO/reduced graphene oxide supported metal/metal oxide nanohybrids) for the green synthesis of biologically relevant molecules, (ii) for metal-free catalysis and (iii) for electrocatalysis, with special focus on graphene contribution to catalytic efficiency. The critical overview and future perspectives are also discussed.