Pt/TiO_2光催化重整降解2-氯乙醇水溶液制氢

Hydrogen Production by Pt/TiO_2 Photocatalytic Reforming Degradation of Aqueous 2-Chloroethanol

在无氧条件下,进行了Pt担载的TiO2光催化有毒的2-氯乙醇(下文简称氯乙醇)重整制氢反应的研究.详细讨论了动力学因素如催化剂表面Pt化学状态、Pt担载量、溶液pH值、氯乙醇浓度等对产氢速率的影响,并用XRD、HNMR、XPS等技术进行了表征,探讨了氯乙醇降解和产氢反应机理.研究表明,在光催化降解氯乙醇的同时产生氢是完全可行的.催化剂表面的Pt以Pt0的化学状态存在,有利于析氢;溶液pH值对产生速率影响也很大,而氯乙醇的浓度变化只是在开始略有影响,浓度的增加对产氢并没有明显的影响.研究得出Pt担载的TiO2光催化重整氯乙醇制氢反应的最佳条件是:Pt的最佳担载量约为1.0%;氯乙醇溶液浓度范围为0.04～0.10M;最佳溶液pH值范围为4～10.

The production of hydrogen by anaerobic photocatalytic reforming degradation of aqueous 2-chloroethanol (chloroethanol, shortened form in the following text) solution has been investigated using a Pt/TiO_2 catalyst. The effect of kinetic factor such as chloroethanol concentration, catalyst surface chemical state, and pH of systems on the photocatalytic production of hydrogen have been studied in detail. The catalyst and the products were characterized by HNMR? XRD and XPS techniques, and the possible photoreaction mechanism was discussed. Both hydrogen production and photocatalytic reforming degradation of aqueous chloroethanol solution have been achieved using a Pt/TiO_2 catalyst. The Pt particles which has been identified as Pt^0 state on the TiO_2 surface are beneficial to hydrogen production. The hydrogen production rate reaches the maximum at ～0.05 M of chloroethanol, the concentration of chloroethanol is (0.04～)0.1 M. The pH affects the hydrogen production rate significantly, and the optimum pH value and Pt loading is 4～10 and about 1.0%.