Volume 19, Issue 11

The book Industrial Green Chemistry, recently published by De Gruyter and co-edited by Serge Kaliaguine and Jean-Luc Dubois, provides several valuable examples of sustainable green chemical processes being developed today. The ten-chapter multi-author book, led by these two reputable researchers, opens a stimulating debate for the scientific community, bringing into focus new perspectives on green chemistry, by describing opportunities for sustainable chemical processes.

Doped zirconium oxide nanoparticles [ZrO 2 ] NPs in the [PEG–H 2 O] and [TiO 2 ] NPs in the [PEG–H 2 O/ZrO 2 ] C matrices to fabricated the [PEG–H 2 O/ZrO 2 +TiO 2 ] h hybrid nanofluid films by a sol–gel method, the average crystallite size is 100 ± 5 nm. The nanofluid and hybrid nanofluid thin films are studied using combined experimental and DFT theoretical method (DMOl 3 ), including FTIR spectrum and optical properties. Mathematically, Higher rate of reactions of rotating [PEG/H 2 O–ZrO 2 ] m , and [PEG–H 2 O/ZrO 2 +TiO 2 ] h nanofluids on an extending sheet is considered with thermal radiation and heat source. The numerical Runge–Kutta–Fehlberg of 4–5th order (RKF45) method is used to solve the issue. The results specifically determine that Δ E g Opt ${\Delta}{E}_{g}^{\text{Opt}}$ values decrease from 2.27 eV for [PEG–H 2 O/ZrO 2 ] m mono nanofluid to 1.596 eV for [PEG–H 2 O/ZrO 2 +TiO 2 ] h hybrid nanofluid using the DFT computations HOMO and LUMO calculation. This result concluded that the [PEG–H 2 O/ZrO 2 ] m transformed from semiconductor to [PEG–H 2 O/ZrO 2 +TiO 2 ] h as a superconductor hybrid nanofluid by addition [TiO 2 ] NPs . The hybrid nanoparticles have a higher influence than nanoparticles on the velocity distributions.

The study of nonideal mixing effect on the dynamic behaviors of CSTRs has very rarely been published in the literature. In this work, Cholette’s model is employed to explore the nonideal mixing effect on the dynamic response of a nonisothermal CSTR. The analysis shows that the mixing parameter n (the fraction of the feed entering the zone of perfect mixing) and m (the fraction of the total volume of the reactor), indeed affect the characteristic roots of transfer function of a real CSTR, which determine the system stability. On the other hand, the inverse response and overshoot response are also affected by the nonideal mixing in a nonisothemal CSTR. These results are of much help for the design and control of a real CSTR.

The mesoporous Ni/KIT-6 catalysts with different composition were prepared by altering reduction temperatures. In addition, their physicochemical properties were characterized by X-ray diffraction, in-situ X-ray photoelectron spectroscopy, and Brunauer–Emmett–Teller techniques. The results shown that the specific surface area, composition and metallic Ni crystallinity of the Ni/KIT-6 catalyst were significantly affected by reduction temperatures. The catalytic performances of the prepared Ni/KIT-6 catalysts were evaluated via the CO 2 reforming of CH 4 into syngas and followed the order: RT0 < RT250 < RT300 < RT350 < RT400 < RT450 ≈ RT500. The specific surface area, pore volume, pore diameter, and Ni 0 content of the most representative RT450 catalyst among of them were 646.7 m 2  g −1 , 0.92 cm 3  g −1 , 6.5 nm, and 30.9%, respectively. The CH 4 and CO 2 conversions of RT450 catalyst reached to 69.0 and 39.4% under a reaction temperature of 600 °C, respectively. The CO selectivity was greater than 49% and the RT450 catalyst had good stability.

Greenhouse gas (GHG) pollution is considered one of the challenging concerns in industrial plants, and to emit the appropriate designation in nitrogen oxide reduction, it is required to implement proper numerical simulation procedures. In this study, ANSYS Fluent ® software is used as dynamic software to solve heat and mass flow transfer numerically by considering non-structured networks for complex geometries. Dry nitrogen oxide burners have an additional thermocouple to provide an extra fuel pathway to combine with air. Then, standard K-ε is used in the numerical simulations to calculate thermal efficiency in combustion processes for turbulent flow regimes. It can cause the removal of 50% of nitrogen oxide into the atmosphere. Furthermore, by the increase of temperature, nitrogen oxide concentration has been increased in the system. After 1975 K, Fuel has been changed to dry fuel, and therefore nitrogen oxide concentration increased because the steam can provide a relatively non-combustible compound increase than fuel. On the other hand, regarding the water volume increase at inlet steam, nitrogen oxide volume percentage has been decreased dramatically, especially in the first periods of water volume increase. Consequently, when the steam percentage is increased instead of water, nitrogen oxide reduction is increased. Moreover, our simulation results have a proper match with Gibbs energy equilibrium.

Low grade phosphate-siliceous slates dump samples (about 11.98% P 2 O 5 ) from Zhanatas deposit, Karatau basin, Kazakhstan were subjected to upgrading in the present study. The suggested upgrading route was to get rid of most of the inorganic carbonates via leaching using organic acids like acetic acid. The effect of leaching temperature, dissolution time, and solid/liquid ratio were studied as the main determental working parameters. It was concluded that a concentrate product containing about 21% P 2 O 5 was produced after leaching with acetic acid at optimum conditions: 30 C 0 , 15 min, and 3:1 liquid/solid ratio. The calculated apparent activation energy of the leaching process showed that the process took place in the intra-diffusion region.

The present research article explored the potential of activated carbon prepared from Limonia acidissima shell to adsorb total Fe ions from aqueous solution in a packed bed up-flow column. The effect of essential factors such as bed height (3–5 cm), initial concentration (30–50 mg/L), and flow rate (3.32–5.4 mL/min) on the performance of the column bed was investigated. The adsorption capacity augmented with an increase in bed height and initial adsorbate concentration but declined with an increase in flow rate. The maximum uptake capacity of 209.6 mg/g was achieved at 5 cm bed height, 3.32 mL/min, and 50 mg/L initial concentration. The bed depth service time (BDST) model was used to analyze the experimental data and determine the characteristic parameters of the packed bed reactor suitable for designing large-scale column studies. The Adams–Bohart, Thomas, and Yoon–Nelson models were applied to the experimental data to predict breakthrough curves using non-linear regression. The artificial neural network (ANN) based model was able to efficaciously predict the column performance using the Levenberg–Marquardt (LM) algorithm. A comparison between the experimental data and model results contributed to a high degree of correlation, specifying that the preliminary information was in good agreement with the ANN predicted data.

Biomass ashes like rice husk ash (RHA), bagasse fly ash (BFA), were used for aqueous phase removal of a pesticide, diuron. Response surface methodology (RSM) and artificial neural network (ANN) were successfully applied to estimate and optimize the conditions for the maximum diuron adsorption using biomass ashes. The effect of operational parameters such as initial concentration (10–30 mg/L); contact time (0.93–16.07 h) and adsorbent dosage (20–308 mg) on adsorption were studied using central composite design (CCD) matrix. Same design was also employed to gain a training set for ANN. The maximum diuron removal of 88.95 and 99.78% was obtained at initial concentration of 15 mg/L, time of 12 h, RHA dosage of 250 mg and at initial concentration of 14 mg/L, time of 13 h, BFA dosage of 60 mg respectively. Estimation of coefficient of determination ( R 2 ) and mean errors obtained for ANN and RSM ( R 2 RHA  = 0.976, R 2 BFA  = 0.943) proved ANN ( R 2 RHA  = 0.997, R 2 BFA  = 0.982) fits better. By employing RSM coupled with ANN model, the qualitative and quantitative activity relationship of experimental data was visualized in three dimensional spaces. The current approach will be instrumental in providing quick preliminary estimations in process and product development.

In the present study, calcium peroxide (CaO 2 ) was used separately for potential application as an environmentally friendly and low-cost oxidant for the removal of a textile dye ‘Reactive Black 5’ (RB5) from simulated textile wastewater containing auxiliary chemicals of textile production. The specific morphology, elemental analysis, particle size distribution, specific surface area, identification of crystalline phases and surface functional groups of the synthesized CaO 2 were investigated by scanning electron microscopy (SEM), energy-dispersive X-ray (EDX), laser diffraction (LD), Brunaure–Emmett–Teller method (BET), X-ray diffraction (XRD) and Fourier transmission infrared (FTIR), respectively. X-ray Diffraction analysis confirmed the synthesized oxidant as CaO 2 with the tetragonal crystalline structure. The signal corresponded to a bending vibration of O–Ca–O was detected in the fingerprint region of the FTIR spectroscopy. The effects of various independent parameters such as contact time, pH, initial RB5 concentration and CaO 2 dosage on decolorization were investigated. The results of the study showed that pH, initial dye concentration and the CaO 2 amounts have significant effects on removal of the RB5. The optimum pH was determined 7 for the removal of RB5 by CaO 2 . 2.0 g CaO 2 was found to be sufficient for the removal of 300 mg/L RB5 with 96.93% removal efficiency. Also 82.8% chemical oxygen demand (COD) removal efficiency from simulated textile wastewater (STW) was obtained by 2.0 g CaO 2 . The results of the present study showed that the CaO 2 can be used as an environmentally friendly and low-cost oxidant for effective removal of reactive textile dyes.