Photocatalytic Hydrogen Generation Using Furfural,Furfuryl Alcohol and Furoic Acid as Electron Donors over Pt/TiO_2

The adsorption of pollutants furfural,furfuryl alcohol and furoic acid on TiO2 is consistent with a Langmuir-Hinshelwood kinetic model,with adsorption constants 9.43×102,3.88×102 and 1.48×103 L/mol,respectively.In 4.00×10-3 mol/L furfural,furfuryl alcohol and furoic acid solution,the efficiency of hydrogen evolution catalyzed by Pt/TiO2 was enhanced respectively by 33.8%,260% and 444% after 10 h irradiation,compared to that in pure water.The pollutants decreased by 10.0%,16.3% and 48.5% and the COD(chemical oxygen demand) by 10.0,18.0 and 28.4 mg/L·h in the reaction system of furfural,furfuryl alcohol and furoic acid after 5 h irradiation,respectively.The initial-pH effect on hydrogen evolution rate was investigated.Under weakly alkaline condition,the rate of the hydrogen generation reached maximum in the reaction systems of furfural and furoic acid,whereas under weakly acidic condition,the rate reached maximum in that of furfuryl alcohol.A possible reaction mechanism was discussed according to the intermediate products of degradation.