对甲基乙苯脱氢制对甲基苯乙烯

研究了对甲基乙苯在水汽存在下以金属氧化物为催化剂的脱氢过程。开发出具有良好反应性能的多组份铁系脱氢催化剂,在620℃、空速1.0h~(-1)(V)、水/烃比2.5(w)和常压下,甲基乙苯转化率66.8%(w),生成甲基苯乙烯的选择性91.2%(w)。考察了工艺参数对甲基乙苯脱氢反应性能的影响及烷基芳烃组成与脱氢反应性能之间的关系,表明烷基芳烃脱氢性能与催化剂类型有关。从不同转化深度时产品的组成分布推测了甲基乙苯脱氢可能的反应历程。

Study of the Dehydrogenation of Para-Ethyltoluene to Para-Vinyltoluene

In this paper,the dehydrogenation process of para-ethyltoluene over a metaloxide catalyst in the presence of steam was reported.An iron based multimetallicoxide catalyst,having good catalytic performance,was developed.At 620℃,with asteam/hhydrocarbon ratio of 2.5(w),1.0 LHSV and under atmospheric pressure,theconversion of ethyltoluene to vinyltoluene was found to be 66.8% with a selec-tivity of 91.2%.The effects of reaction parameters on catalytic properties andthe relationship between alkyl-aromatic compounds and their reactivity wereinvestigated for dehydrogenation of ethyltoluene to vinyltoluene.It was shownthat the catalytic dehydrogenation properties of alkyl-aromatics were related tothe type of catalyst.A possible reaction pathway for the dehydrogenation ofethyltoluene was speculated from distribution of products at various conversionrates.