The Effects Of Organic Groups In Photocatalytic Hydrogen Production With TiO₂and Studies On Hydrogen Production Process Of Wastewater

Photocatalytic hydrogen production is a hot and difficult spot in catalytic fields, and the usage of organics in generating H2is an important issue. Most of the industrial wastewater is organic wastewater, and studying photocatalytic H2production of organics could combine degradation of pollutants with production of clean energy, achieving dual goals.Sol-gel, hydrothermal and photoassisted platinum deposition methods were used to prepare Pt-TiO2nanotube catalysts, we found that the5:10:1molar ratio of water, alcohol and n-butyl titanate,60minutes Pt loading time and0.5%Pt loading amount are the best conditions in preparing catalysts. The SEM images show that catalysts have ideal tubular morphology and large specific surface area.organic and water molecules co-adsorbing on the catalyst surface at the same quantity levels about9hours shows the highest H2production efficiency. H-NMRs reveal that cracking of organic molecules takes place on the catalyst surface. Transitional products on the catalyst surface can not desorbed because of the shackle of hydrogen bonds, until form CO2. Due to the factors of molecular steric, hydroxyl radicals implanted and the breaking of C-C bonds, H2generation activity of multi-branched, long-chain and too many-OH or-COOH functional groups organics are inhibited.Because of the electronic effects caused by amines, alkanolamines have a stronger adsorption capacity of-OH and a weaker breaking difficulty of C-C bonds, and the best H2generation activity. Ethers, ketones, esters and alkanes lacking the adsorption capacity of hydrogen bonds caused by-OH have the negative activity. Benzene ring organics can not produce H2because of its strong stability. All in all, absorption between organic molecules and catalysts, and efficiency of-OH implantation are the two most important factors in generating H2.pH=10,40℃reaction temperature,0.09g catalysts addition amount,20dilution times, and20hours reaction time are the best conditions in generating H2by pharmaceutical wastewater. Bear-wastewater can not generate H2. Low concentration azo dyes also can not generate H2but have some decolorization effects. Organics can produce some H2over sunlight but have a low efficiency.The elaboration of hydrogen production mechanism process of organic molecules, and the wastewater degradation combinating with hydrogen production are two innovations of this paper.