KINETIC PECULIARITY OF CO-PRODUCTION OF BENZENE AND NAPHTHALENE FROM AROMATIC MIXTURES BY THERMAL HYDRODEALKYLATION

ABSTRACT

The kinetic peculiarity of aromatic and non-aromatic hydrocarbons under co-production process conditions of benzene and naphthalene from pyrolysis gasoline or other industrial aromatic mixtures through thermal hydrodealkylation was experimentally investigated. In these experiments, various model mixtures of such pure hydrocarbons as benzene, toluene, naphthalene, 1-, 2-methylnaphtalenes and n-heptane were used as raw materials, and under thermal hydrodealkylation conditions, conversion kinetics of these hydrocarbons and their effects to each other were studied. According to the experimental results obtained, the conversion rates in descending order are as n-heptane > 1-methylnaphthalene (1-MN) > 2-methylnaphthalene (2-MN) > toluene. N-heptane considerably accelerates the hydrodealkylation reactions of both toluene and 1-MN and 2-MN. While 1- MN and 2-MN increase the rate of toluene's conversion to some extent, toluene can prevent their conversion. Furthermore, n-heptane has an increasing impact on the reaction rate of benzene's conversion into biphenyl. At temperature of 625°C and in a long contact time (60 s or more) almost all of n-heptane is converted into mostly alkanes, C1–C3 gases.     

神华蒙西8万t/a苯加氢项目萃取精制系统工艺技术改造

介绍了神华蒙西公司8万t/a苯加氢项目萃取塔回流系统回流罐体积小、油水分离不彻底,造成外排废水中带油。另外,萃取塔顶非芳烃中苯含量过高。通过理论计算,找出了萃取塔顶部非芳烃含苯量高的原因,并进行了相应的技术改造,解决了油水分离不彻底的问题。同时,也使塔顶非芳烃中苯的含量,从原来的60%下降到15%左右,减少了苯的损失,为公司创造了效益。