分子筛催化噻吩类硫化物与烯烃烷基化脱硫研究

Alkylation of Thiophenic Sulfur Compounds with Olefin over Zeolite Catalysts

采用GC—FPD,GC—MS,NH3-TPD及BET等手段,以噻吩,2-甲基噻吩,3-甲基噻吩,2-乙基噻吩及2,5-二甲基噻吩为模型硫合物,异丁烯为烷基化剂,对HZSM-5,Hβ,HM,HY,HMCM-41等分子筛为催化剂催化噻吩类硫化物与异丁烯的烷基化反应进行了研究,并比较不同分子筛的酸强度分布及孔径大小对噻吩类硫化物与异丁烯的烷基化反应性能的影响。结果表明,Hβ,HM,HY,HMCM-41催化剂催化噻吩与异丁烯的烷基化反应在温和的反应条件下(如80℃,常压)即可达到较高的转化率,分子筛催化剂的孔径大小是影响催化活性的关键因素。

A desulfurization method was proposed for the removal of sulfur compounds from FCC gasoline by alkylation of thiophenic derivative with olefins over zeolite catalysts, and the alkylated thiophenes were concentrated in the heavy fraction of the FCC gasoline by distillation. Five types of zeolite catalysts, including HZSM-5, Hβ, HM, HY and HMCM-41, had been investigated by means of GC-FPD, GC-MS, NH3-TPD and BET, and the alkylation performances of model sulfur compounds, such as thiophene, 2-methylthiophene, 3-methylthiophene, 2-ethylthiophene and 2,5-dimethylthiophene, with isobutylene were correlated with the distribution of acidity and pore diameter of zeolite catalysts as above. The results showed that the alkylation of the model sulfur compounds with isobutylene over Hβ, HM, HY and HMCM-41 zeolite catalysts was easy and conversions were near to 100% at mild reaction conditions (e.g. 80°C, air-pressure), and the pore diameter of zeolite was the key factor of the influence on the catalytic activity.