The conversion of ethanol to hydrocarbons over ZSM-5,H-ZSM-5 or Zn-ZSM-5 zeolite catalysts was studied in a fixed-bed reactor in the temperature range of 280-450 ℃.The liquid hydrocarbons in the products were analyzed by means of GC-MS and the major products were C5-9 olefins,C4-7 alkane and C6-11 aromatics.On ZSM-5,the maximum selectivities to benzene,toluene and xylene were 5.94％,24.81％ and 33.21％ at 425,425 and 450 ℃,respectively.On Zn-ZSM-5,the maximum selectivities to benzene,toluene and xylene were 5.99％,24.45％ and 37.89％ at 380,450 and 380 ℃,respectively.On H-ZSM-5,the maximum selectivities to benzene,toluene and xylene were 7.08％,27.60％ and 30.23％ at 380,380 and 450 ℃,respectively.The yield of the liquid hydrocarbons decreased with increasing the silica-alumina ratio at a constant temperature,and first increased and then decreased with temperature rise at a constant silica-alumina ratio.When the silica-alumina ratio was 25,the maximum yield of liquid hydrocarbons was 17.7％,13.8％ and 16.3％ on ZSM-5,Zn-ZSM-5 and H-ZSM-5 at 320,320 and 380 ℃,respectively.%以ZSM-5,H-ZSM-5,Zn-ZSM-5为催化剂,在280～450℃范围内,乙醇在固定床反应器上转化为气相烃、液相烃和水.液相烃经GC-MS检测,主要成分是C5-9烯烃、C4-7烷烃和C6-11芳烃.实验结果表明,ZSM-5催化剂上,温度为425℃时,苯和甲苯选择性最大,分别为5.94％和24.81％；温度为450℃时,二甲苯选择性最大,为33.21％.Zn-ZSM-5催化剂上,温度为380℃时,苯和二甲苯选择性最大,分别为5.99％和37.89％；温度为450℃时,甲苯选择性最大,为24.45％.H-ZSM-5催化剂上,温度为380℃时,苯和甲苯选择性最大,分别为7.08％和27.60％；温度为450℃时,二甲苯选择性最大,为30.23％.硅铝比和反应温度对液相烃收率有显著影响,反应温度一定时,随硅铝比的增大,液相烃收率减小；硅铝比一定时,随反应温度的升高,液相烃收率先增大后减小.硅铝比为25时,ZSM-5和Zn-ZSM-5催化剂上,320℃下液相烃收率最大,分别为17.7％和13.8％;H-ZSM-5催化剂上,380℃下液相烃收率最大,为16.3％.
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