通过沉积沉淀法制备了Au负载量为3%的Au/CeO2催化剂,并利用表征手段结合固定床反应器试验研究了催化剂的理化特性和催化水煤气变换反应(water gas shift reaction,WGSR)的活性.结果表明:Au元素均匀地分散在了载体表面,改善了催化剂的氧...通过沉积沉淀法制备了Au负载量为3%的Au/CeO2催化剂,并利用表征手段结合固定床反应器试验研究了催化剂的理化特性和催化水煤气变换反应(water gas shift reaction,WGSR)的活性.结果表明:Au元素均匀地分散在了载体表面,改善了催化剂的氧化还原性能和CO吸附性能,进而提高了催化剂的活性,当反应温度为300℃时,WGSR试验中CO转化率提高了56.0%,O2促进了催化剂表面碳酸盐类物质的分解,恢复了催化剂的表面活性位,明显提高了低温下CO的转化率;当反应温度在200,250℃时,CO转化率分别提高了15.0%和17.5%.展开更多
To investigate the effects of chlorine on the Au/ceria catalysts,the adsorption of gold or chlorine and their coadsorpiton on the stoichiometric and partially reduced CeO2（111） surfaces are studied from the first pr...To investigate the effects of chlorine on the Au/ceria catalysts,the adsorption of gold or chlorine and their coadsorpiton on the stoichiometric and partially reduced CeO2（111） surfaces are studied from the first principles.It is found that the adsorption of Au is significantly enhanced by the chlorine preadsorption on the stoichiometric CeO2（111） surface;while on the partially reduced CeO2（111） surface,the preadsorbed chlorine inhabits the oxygen vacancy（which is the preferred adsorption site for gold）,leading to a CeOCl phase and the dramatical weakening of the Au adsorption.Therefore,chlorine on the CeO2（111） surface can affect the Au adsorption thus the activity of the Au/CeO2 catalyst.展开更多
文摘通过沉积沉淀法制备了Au负载量为3%的Au/CeO2催化剂,并利用表征手段结合固定床反应器试验研究了催化剂的理化特性和催化水煤气变换反应(water gas shift reaction,WGSR)的活性.结果表明:Au元素均匀地分散在了载体表面,改善了催化剂的氧化还原性能和CO吸附性能,进而提高了催化剂的活性,当反应温度为300℃时,WGSR试验中CO转化率提高了56.0%,O2促进了催化剂表面碳酸盐类物质的分解,恢复了催化剂的表面活性位,明显提高了低温下CO的转化率;当反应温度在200,250℃时,CO转化率分别提高了15.0%和17.5%.
基金supported by the National Natural Science Foundation of China(Grant Nos.11174070,51401078,and 11147006)the China Postdoctoral Science Foundation(Grant No.2012M521399)+2 种基金the Postdoctoral Research Sponsorship in Henan Province,China(Grant No.2011038)the Foundation for the Key Young Teachers of Henan Normal UniversityStart-up Foundation for Doctors of Henan Normal University,China
文摘To investigate the effects of chlorine on the Au/ceria catalysts,the adsorption of gold or chlorine and their coadsorpiton on the stoichiometric and partially reduced CeO2（111） surfaces are studied from the first principles.It is found that the adsorption of Au is significantly enhanced by the chlorine preadsorption on the stoichiometric CeO2（111） surface;while on the partially reduced CeO2（111） surface,the preadsorbed chlorine inhabits the oxygen vacancy（which is the preferred adsorption site for gold）,leading to a CeOCl phase and the dramatical weakening of the Au adsorption.Therefore,chlorine on the CeO2（111） surface can affect the Au adsorption thus the activity of the Au/CeO2 catalyst.
