An Investigation Of Degradating Organic Compound In Waste Water By Combinatorial Photocatalytic Method

Photocatalysis degradation was proved to be an efficient approach for the purification of air and water. In this area, Maier et al. developed a high throughput technology for photocatalytic degradation of organic pollutant based on HPLC screening technology, and shorted the time for catalyst discovering, however the analysis rate of HPLC can not catch up the reaction rate. Hence, it is desired to design a real high throughput analysis method to meet the requirement of this investigation.In this work, we have designed a combinatorial reactor, and a fluorescence imaging analysis system, which can simultaneously conduct more than 100 catalytic reactions and analysis these samples in seconds. The results from our fluorescence imaging analysis were compared with that from the traditional UV method. For the same catalysts, we have obtained the same results based on both of our fluorescence imaging analysis and the traditional UV analysis.In the current investigation, the influence of polymer P1 (HO(CH₂CH₂O)20(CH₂CH(CH₃)O)70(CH₂CH₂O)20H) employing in catalyst synthesis on catalytic behavour was explored. The polymer P1 acts as a template in the catalyst synthesis. The catalyst library was synthesized on a quartz sand substrat (specific surface area 1.73 m2/g). It was proved that the catalysts prepared by using P1 as template were more active than the regular catalysts.The investigation indicate that under UV light, in both the P1 templated ZrO₂-TiO₂-Nb₂O₅-WO3 catalyst library and regular ZrO₂-TiO₂-Nb₂O₅-WO3 catalytic library, the addition of ZrO₂ to TiO₂ did not result in significant improvement in catalytic activities, whereas apparent improvement was observed when Nb₂O₅ or WO3 was added into TiO₂. When Nb₂O₅ and WO3 were co-doped into TiO₂, the tertiary catalysts exhibited higher catalytic activities. The catalysts containing 20³0% of Nb₂O₅ and 10²0% ofWO3 (balanced with TiO₂) are superior to any of pure TiO₂, Nb₂O₅, WO3, and the binary catalysts composed of any two of TiO₂, Nb₂O₅, and WO3. Our study has demonstrated that besides the traditional TiO₂-domain catalysts, active photo-degradation catalysts can be prepared by combination of Nb₂O₅, WO3, and ZrO₂.The catalyst libraries ZrO₂-WO3-TiO₂, V₂O₅-MoO3-TiO₂, and ZrO₂-Nb₂O₅-WO3 prepared with P1 template were tested under visible light. Our study has demonstrated that ZrO₂ to TiO₂ did not result in significant improvement in catalytic activities, whereas marked improvement was observed when WO3 was added into TiO₂;in the V₂O₅-MoO₃-TiO₂ catalyst library, catalyst with composition 20～30%TiO₂-30～50% MoO₃-40～60%V₂O₅ is the most active catalyst. In catalyst library ZrO₂-Nb₂O₅-WO₃, the addition of ZrO₂ into Nb₂O₅ did not improve catalytic activities, but the employing of WO₃ could enhance the catalytic activity of Nb₂O₅. The catalyst with composition 80%WO₃-20%Nb₂O₅ showed the highest activity.