四氢萘加氢裂解反应行为及重整C_(10)^(+)芳烃利用方案研究

Study on Hydrocracking Behavior of Tetrahydronaphthalene andUtilization Scheme of Reforming C_(10)^(+)Aromatics

考察了四氢萘的裂解行为,研究了分子筛类型、金属改性以及金属间相互作用对四氢萘裂解性能的影响。结果表明:四氢萘裂解反应行为与分子筛孔结构和酸性质密切相关,ZSM-5分子筛拥有酸强度和酸量的优势,四氢萘裂解反应的选择性最高;β沸石拥有最大孔道尺寸,四氢萘转化率最高,但其氢转移及烷基化等副反应会生成大量的萘系物等重芳烃;金属Ni改性可以提升β沸石加氢裂解活性,且能降低其氢转移和烷基化选择性;Cu和Ni之间存在的“氢溢流”协同催化效应可以大幅度提高β沸石四氢萘的转化率,降低氢转移和烷基化反应选择性,提升裂解的单环芳烃收率。

The cracking behavior of tetrahydronaphthalene was investigated,and the effects of molecular sieve type,metal modification and metal interaction on the cracking performance of tetrahydronaphthalene were studied.The results showed that the reaction behavior of tetrahydronaphthalene cracking was closely related to the pore structure and acid properties of the molecular sieve.ZSM-5 molecular sieve had the highest acid content and strong acid strength,and the selectivity of tetrahydronaphthalene cracking reaction was the highest.βzeolite has the largest pore size and the conversion rate of tetrahydronaphthalene was the highest.However,the hydrogen transfer and alkylation and other side reactions can produce a large number of heavy aromatics such as naphthalene series.Ni modification can improve the hydrocracking activity ofβzeolite and reduce the hydrogen transfer and alkylation selectivity.The“hydrogen overflow”synergistic catalytic effect between Cu and Ni can greatly improve the conversion rate ofβzeolite tetrahydronaphthalene,reduce the selectivity of hydrogen transfer and alkylation reaction,and increase the yield of single cyclic aromatic hydrocarbons.