摘要
考察了 Pt/CeO_2/Al_2O_3 催化剂在含硫和无硫的条件下对汽油典型模型组分(甲苯、正庚烷、1-辛烯和环己烷)的蒸汽重整反应性能,并用 X 射线衍射、程序升温还原和热重分析等方法对催化剂进行了表征,探讨了该催化剂在零售汽油蒸汽重整反应中失活的原因。实验结果表明,无硫时,该催化剂对各模型组分均表现出良好的活性及稳定性;但在硫含量为300μg/g 时,该催化剂上甲苯和环己烷的转化率显著降低;1-辛烯的初始转化率略有降低,但反应稳定性较差;只有正庚烷的转化率没有明显变化。含硫条件下,催化剂对烯烃、芳烃和环烷烃的蒸汽重整性能显著下降的原因是催化剂中 Pt-CeO_2 键被破坏,导致催化剂硫中毒,而硫中毒加速了催化剂表面积碳。
The stability and sulfur tolerance of Pt/CeO2/Al2O3 catalyst in steam reforming （SR） of retail gasoline was not better than that in SR of iso-octane with 300 μg/g sulfur. SR of various typical model components, namely toluene, n-heptane, 1-octene and cyclohexane, in gasoline with or without sulfur was carried out. Pt/CeO2/Al2O3 catalyst were characterized by means of XRD, He-TPR and TG to reveal the difference in SR of retail gasoline and iso-octane. In the absence of sulfur, Pt/CeO2/Al2O3 catalyst exhibited good activity and stability in SR of the said gasoline model components. In the presence of 300 μg/g sulfur, conversions of toluene and cyclohexane decreased significantly. Although initial conversion of 1-octene reduced only slightly but the steadiness of reaction declined. Sulfur imposed no influence on catalyst performance in SR of n-heptane. Deactivation of the catalyst in SR of toluene, 1-octene and cyclohexane with sulfur is due to the destroy of Pt-CeO2 bond, which accelerated surface carbon deposition.
出处
《石油化工》
CAS
CSCD
北大核心
2008年第7期662-666,共5页
Petrochemical Technology
基金
国家自然科学基金项目(20590366
20573036)
"863"计划项目(2007AA05Z101)
新世纪优秀人才支持计划项目(06-NCET-0423)
上海市"曙光计划"项目(06SG28)
上海市重点学科建设项目(B409)
关键词
汽油
蒸汽重整
铂
氧化铈
抗硫中毒
催化剂
制氢
gasoline
steam reforming
platinum
cerium oxide
sulfur tolerance
catalyst
hydrogen production
