Title: | Solar photocatalytic gas-phase degradation of n-decane--a comparative study using cellulose acetate monoliths coated with P25 or sol-gel TiO(2) films |
Author(s): | Miranda SM; Lopes FV; Rodrigues-Silva C; Martins SD; Silva AM; Faria JL; Boaventura RA; Vilar VJ; |
Address: | "LSRE-Laboratory of Separation and Reaction Engineering, Associate Laboratory LSRE/LCM, Faculdade de Engenharia, Universidade do Porto, Rua Dr. Roberto Frias, Porto, 4200-465, Portugal" |
Journal Title: | Environ Sci Pollut Res Int |
DOI: | 10.1007/s11356-014-2952-2 |
ISSN/ISBN: | 1614-7499 (Electronic) 0944-1344 (Linking) |
Abstract: | "Cellulose acetate monoliths (CAM) were used as the substrate for the deposition of TiO2 films to produce honeycombed photoactive structures to fill a tubular photoreactor equipped with a compound parabolic collector. By using such a setup, an efficient single-pass gas-phase conversion was achieved in the degradation of n-decane, a model volatile organic compound. The CAM three-dimensional, gas-permeable transparent structure with a rugged surface enables a good adhesion of the catalytic coating. It also provides a rigid structure for packing the tubular photoreactor, and maximizing the illuminated catalyst surface. The efficiency of the photocatalytic oxidation (PCO) process on n-decane degradation was evaluated under different operating conditions, such as feeding concentration (73 and 146 ppm), gas stream flow rate (73, 150, and 300 mL min(-1)), relative humidity (3 and 25 %), and UV irradiance (18.9, 29.1, and 38.4 WUV m(-2)). The results show that n-decane degradation by neat photolysis is negligible, but mineralization efficiencies of 86 and 82 % were achieved with P25-CAM and SG-CAM, respectively, for parent pollutant conversions above 95 %, under steady-state conditions. A mass transfer model, considering the mass balance to the plug-flow packed photoreactor, and PCO reaction given by a Langmuir-Hinshelwood bimolecular non-competitive two types of sites equation, was able to predict well the PCO kinetics under steady-state conditions, considering all the operational parameters tested. Overall, the performance of P25-CAM was superior taking into account mineralization efficiency, cost of preparation, surface roughness, and robustness of the deposited film" |
Keywords: | Air Pollutants/*chemistry Alkanes/*chemistry Catalysis Cellulose/analogs & derivatives Kinetics Organic Chemicals Oxidation-Reduction *Photolysis Titanium/*chemistry Ultraviolet Rays Volatile Organic Compounds/*chemistry; |
Notes: | "MedlineMiranda, Sandra M Lopes, Filipe V S Rodrigues-Silva, Caio Martins, Susana D S Silva, Adrian M T Faria, Joaquim L Boaventura, Rui A R Vilar, Vitor J P eng Comparative Study Evaluation Study Research Support, Non-U.S. Gov't Germany 2014/05/09 Environ Sci Pollut Res Int. 2015 Jan; 22(2):820-32. doi: 10.1007/s11356-014-2952-2. Epub 2014 May 9" |