Abstract
The influence of sonicating a TiO2 suspension was studied and, in addition, the effect of the TiO2 aggregate size. 2,4-Dichlorophenol (DCP) was degraded by photocatalysis with TiO2. In a first experimental series, the suspension was prepared just stirring the photocatalyst. Then, the experimental runs were repeated but stirring and sonicating the TiO2. The sonicated suspension showed to be much more effective than the non-sonicated, and the kinetic constants were around 70% higher for DCP removal and 40% higher for total organic carbon (TOC) mineralization. The absorption and scattering coefficients and the diffuse reflectance were also determined and presented for both types of suspensions. The values were calculated by transmittance measurements for different amounts of TiO2. The values obtained were fitted to the radiative transfer equation using the Schuster–Schwarzschild approximation. In agreement with the results of the degradation experiments, it was found that the absorption coefficient was higher for the sonicated suspension.
References
1. Malato S, Fernández-Ibañez P, Maldonado MI, Blanco J, Gernjak W. Decontamination and disinfection of water by solar photocatalysis: recent overview and trends. Catal Today 2009;147:1–59.10.1016/j.cattod.2009.06.018Suche in Google Scholar
2. Mccullagh C, Robertson JMC, Bahnemann DW, Robertson PKJ. The application of TiO2 photocatalysis for disinfection of water contaminated with pathogenic micro-organisms: a review. Res Chem Intermediat 2007;33:359–75.10.1163/156856707779238775Suche in Google Scholar
3. Henderson MA. A surface science perspective on TiO2 photocatalysis. Surf Sci Rep 2011;66:185–297.10.1016/j.surfrep.2011.01.001Suche in Google Scholar
4. Almquist CB, Biswas P. Role of synthesis method and particle size of nanostructured TiO2 on its photoactivity. J Catal 2002;212:145–56.10.1006/jcat.2002.3783Suche in Google Scholar
5. Maira AJ, Yeung KL, Lee CY, Yue PL, Chan CK. Size effects in gas-phase photo-oxidation of trichloroethylene using nanometer-sized TiO2 catalyst. J Catal 2000;192:185–96.10.1006/jcat.2000.2838Suche in Google Scholar
6. Jiang J, Oberdörster G, Biswas P. Characterization of size, surface charge, and agglomeration state of nanoparticle dispersions for toxicological studies. J Nanoparticle Res 2009;11:77–89.10.1007/s11051-008-9446-4Suche in Google Scholar
7. Fernández-Ibañez P, Malato S, de las Nieves FJ. Relationship between TiO2 particle size and reactor diameter in solar photoreactors efficiency. Catal Today 1999;54:195–204.10.1016/S0920-5861(99)00182-0Suche in Google Scholar
8. Yokota T, Cesur S, Suzuki H, Baba H, Takahata Y. Anisotropic scattering model for estimation of light absorption rates in photoreactor with heterogeneous medium. J Chem Eng Jpn 1999;32:314–21.10.1252/jcej.32.314Suche in Google Scholar
9. Curco D, Gimenez J, Addardak A, Cervera-March S, Esplugas S. Effects of radiation absorption and catalyst concentration on the photocatalytic degradation of pollutants. Catal Today 2002;76:177–88.10.1016/S0920-5861(02)00217-1Suche in Google Scholar
10. Satuf ML, Brandi RJ, Cassano AE, Alfano OM. Experimental method to evaluate the optical properties of aqueous titanium dioxide suspensions. Ind Eng Chem Res 2005;44:6643–9.10.1021/ie050365ySuche in Google Scholar
11. Cabrera MI, Alfano OM, Cassano AE. Absorption and scattering coefficients of titanium dioxide particulate suspensions in water. J Phys Chem 1996;100:20043–50.10.1021/jp962095qSuche in Google Scholar
12. Yurdakal S, Loddo V, Bayarri B, Palmisano G, Augugliaro V, Giménez J, et al. Optical properties of TiO2 suspensions: influence of pH and powder concentration on mean particle size. Ind Eng Chem Res 2007;46:7620–6.10.1021/ie070205hSuche in Google Scholar
13. Loddo V, Addamo M, Augugliaro V, Palmisano L, Schiavello M. Optical properties and quantum yield determination in photocatalytic suspensions. AIChE J 2006;52:2565–74.10.1002/aic.10883Suche in Google Scholar
14. Modest MF. Radiative heat transfer. McGraw-Hill: New York, 1993.Suche in Google Scholar
15. Cassano AE, Alfano OM. Reaction engineering of suspended solid heterogeneous photocatalytic reactors. Catal Today 2000;58:167–97.10.1016/S0920-5861(00)00251-0Suche in Google Scholar
16. Brandi RJ, Alfano OM, Cassano AE. Rigorous model and experimental verification of the radiation field in a flat solar collector simulator employed for photocatalytic reactions. Chem Eng Sci 1999;54:2817–27.10.1016/S0009-2509(98)00355-8Suche in Google Scholar
17. Kortum G. Reflectance spectroscopy: principles, methods, applications. New York, NY: Springer-Verlag, 1969.10.1007/978-3-642-88071-1Suche in Google Scholar
18. Arancibia-Bulnes CA, Bandala ER, Estrada CA. Radiation absorption and rate constants for carbaryl photocatalytic degradation in a solar collector. Catal Today 2002;76:149–59.10.1016/S0920-5861(02)00215-8Suche in Google Scholar
©2013 by Walter de Gruyter Berlin / Boston
Artikel in diesem Heft
- Masthead
- Masthead
- Editorial
- In Honor of Alberto E. Cassano: Researcher, Engineer, and Academic
- Articles
- From Ideal Reactor Concepts to Reality: The Novel Drum Reactor for Photocatalytic Wastewater Treatment
- Synthesis, Characterization, and Comparison of Sol–Gel TiO2 Immobilized Photocatalysts
- Determination of Kinetic Parameter in a Unified Kinetic Model for the Photodegradation of Phenol by Using Nonlinear Regression and the Genetic Algorithm
- Mass Transfer and Conservation from a Finite Source to an Infinite Media
- Modelling and Simulation of Gas–liquid Hydrodynamics in a Rectangular Air-lift Reactor
- Two-Dimensional Modeling of an Externally Irradiated Slurry Photoreactor
- Role of Aspect Ratio and Joule Heating within the Fluid Region Near a Cylindrical Electrode in Electrokinetic Remediation: A Numerical Solution based on the Boundary Layer Model
- Solar Water Disinfection Using NF-codoped TiO2 Photocatalysis: Estimation of Scaling-up Parameters
- A Simple and Semi-Empirical Model to Predict THMs Generation in Water Facilities Including pH Effects
- On the Standardization of the Photocatalytic Gas/Solid Tests
- Microalgae Technology: A Patent Survey
- Influence of Physical and Optical Parameters on 2,4-Dichlorophenol Degradation
- Factors Capable of Modifying the Response of Pseudomonas aeruginosa to the Inactivation Induced by Heterogeneous Photocatalysis
- Enhanced Antibacterial Activity of CeO2 Nanoparticles by Surfactants
- Determination of Photochemical, Electrochemical and Photoelectrochemical Efficiencies in a Photoelectrocatalytic Reactor
- Correlations between Molecular Descriptors from Various Volatile Organic Compounds and Photocatalytic Oxidation Kinetic Constants
- Role of Joule Heating in Electro-Assisted Processes: A Boundary Layer Approach for Rectangular Electrodes
Artikel in diesem Heft
- Masthead
- Masthead
- Editorial
- In Honor of Alberto E. Cassano: Researcher, Engineer, and Academic
- Articles
- From Ideal Reactor Concepts to Reality: The Novel Drum Reactor for Photocatalytic Wastewater Treatment
- Synthesis, Characterization, and Comparison of Sol–Gel TiO2 Immobilized Photocatalysts
- Determination of Kinetic Parameter in a Unified Kinetic Model for the Photodegradation of Phenol by Using Nonlinear Regression and the Genetic Algorithm
- Mass Transfer and Conservation from a Finite Source to an Infinite Media
- Modelling and Simulation of Gas–liquid Hydrodynamics in a Rectangular Air-lift Reactor
- Two-Dimensional Modeling of an Externally Irradiated Slurry Photoreactor
- Role of Aspect Ratio and Joule Heating within the Fluid Region Near a Cylindrical Electrode in Electrokinetic Remediation: A Numerical Solution based on the Boundary Layer Model
- Solar Water Disinfection Using NF-codoped TiO2 Photocatalysis: Estimation of Scaling-up Parameters
- A Simple and Semi-Empirical Model to Predict THMs Generation in Water Facilities Including pH Effects
- On the Standardization of the Photocatalytic Gas/Solid Tests
- Microalgae Technology: A Patent Survey
- Influence of Physical and Optical Parameters on 2,4-Dichlorophenol Degradation
- Factors Capable of Modifying the Response of Pseudomonas aeruginosa to the Inactivation Induced by Heterogeneous Photocatalysis
- Enhanced Antibacterial Activity of CeO2 Nanoparticles by Surfactants
- Determination of Photochemical, Electrochemical and Photoelectrochemical Efficiencies in a Photoelectrocatalytic Reactor
- Correlations between Molecular Descriptors from Various Volatile Organic Compounds and Photocatalytic Oxidation Kinetic Constants
- Role of Joule Heating in Electro-Assisted Processes: A Boundary Layer Approach for Rectangular Electrodes