摘要
考察了HY,Hβ,HZSM-5,SAPO-11四种分子筛催化剂对FCC汽油中噻吩类含硫化合物烷基化反应深度脱硫的影响。结果表明:在360℃,1MPa的反应条件下,强酸酸量比例大、B酸中心多的HZSM-5分子筛催化剂能达到催化噻吩类含硫化合物与烯烃进行烷基化转化的目的,使汽油中大部分含硫化合物经烷基化反应生成大分子含硫化合物进入更高沸点的馏分油中;另一方面,HZSM-5分子筛独特的孔结构能够有效地减少噻吩类的过度缩合,减少生焦和烯烃类的多聚,最大限度保证汽油产品收率。以量子力学理论为基础,运用分子模拟手段计算噻吩类含硫化合物的动力学直径,研究了含硫化合物及烯烃与ZSM-5的化学吸附作用,并根据计算结果提出了在分子筛催化体系中噻吩类含硫化合物烷基化的反应历程。
Alkylation reactions of thiophenic compounds contained in FCC naphtha on zeolite catalysts with HY, Hβ, HZSM-5 and SAPO-11 active components were investigated respectively. As a result, HZSM-5, which has large contents of both strong acid sites and bronsted acid sites, had the highest alkylation activity and selectivity for thiophenic compounds reacted with olefins. Certain sulfur-containing impurities could be converted to larger molecules having higher boiling points within the range of diesel fraction. ZSM-5 zeolite has its unique pore structure, which effectively reduced the over-condensation of thiophenic compounds, as well as lowered the oligomerization of olefins and decreased the coke yield, and resulted in high yield of naphtha. Based on the quantum mechanics, the chemical adsorption function of sulfur compounds with olefins on ZSM-5 was studied by using molecular simulation to calculate the kinetic diameters of the thiophenic compounds. According to the calculation results, the alkylation reaction path of thiophenic compounds on zeolite was proposed.
出处
《石油炼制与化工》
CAS
CSCD
北大核心
2005年第2期38-42,共5页
Petroleum Processing and Petrochemicals
