载体对Au催化剂乙醇部分氧化制氢性能的影响

Effect of Support on Catalytic Performance of Au Catalyst for Partial Oxidation of Ethanol to Generate Hydrogen

关键词:  贵金属  载体  催化剂

Key words:  noble metal  support  catalyst

摘要:

采用共沉淀制备方法分别制备Au/Al₂O₃、Au/ZnO、Au/CeO₂、Au/Fe₂O₃催化剂,考察不同载体对乙醇部分氧化制氢性能的影响,并用XRD、H₂-TPR、H₂-TPD等对各催化剂的晶相结构、表面还原性、吸附性能等进行表征,考察载体对Au催化剂的活性和选择性的影响。结果表明,载体对Au催化剂的催化性能与H₂的选择性能具有较大的影响,CeO₂载体负载Au催化剂,活性组分Au与载体能形成较强的相互作用,表面存在较多的氧物种,并在乙醇部分氧化制氢反应中表现较好的活性和选择性,当反应温度为450℃时,乙醇转化率为96.0%,H₂选择性达到86.3%。

Abstract:

A series of Au catalysts supported on Al₂O₃, ZnO, CeO₂ and Fe₂O₃ were prepared by co-precipitation method, and the crystalline structure, surface reduction and adsorption properties of the catalysts were characterized by XRD, H₂-TPR and H₂-TPD techniques.At the same time, the catalytic activity and selectivity were investigated.The results showed that the supports had a great impact on Au catalysts.For the Au catalyst loaded on CeO₂, the active component Au and the CeO₂ carrier could form a strong interaction and there were more oxygen species on the surface of the catalyst.The Au/CeO₂ catalyst revealed more excellent activity and selectivity for producing hydrogen from ethanol partial oxidation.When the reaction temperature was 450℃, the ethanol conversion rate and H₂ selectivity reached 96.0% and 86.3%.