溶剂对环戊二烯加氢的影响

Solvent Effection on the Hyorogenation of Cyclopentadiene

溶剂对环戊二烯（ＣＰＤ）液相加氢行为有明显的影响。在３０℃、１１０×１０５～１２３×１０５ＰａＨ２、骨架镍催化的条件下，ＣＰＤ在甲醇、乙醇、异丙醇、苯、甲苯等溶剂中的加氢反应是分步进行的。即先生成环戊烯（ＣＰＥ），且对ＣＰＤ浓度表现为零级反应，再生成环戊烷（ＣＰＡ）。而在二氯乙烷、二氯甲烷中反应则没有明显的这种分步性。苯是较好的ＣＰＤ选择性加氢生成ＣＰＥ的溶剂。在ＣＰＤ∶苯＝２∶２５（体积比）、３０℃、１１０×１０５～１２０×１０５Ｐａ、骨架镍催化的条件下，ＣＰＥ的反应选择性达９９５％、摩尔收率达９０１％。

To the hydrogenation of cyclopentadiene (CPD) in liquid phase, the kinetic performance was markedly influenced by solvent.When the reaction was carried out in solvents of methanol, ethanol, isopropanol, benzene, and toluene respectively at 30℃,110×105～123×105Pa of hydrogen , Raney Ni catalyst, cyclopentene(CPE) was formed in the first step with a feature of zero order reaction to CPD concentration, and cyclopentane(CPA) was then formed in the second step by CPE hydrogenation. However, when the reaction was carried out in solvent of dichloromethane or dichloroethane, CPE and CPA were formed simultaneously.The cyclopentadiene hydrogenation rate was also obviously influenced by solvent.The CPE formation rate(r) was decreased in the order:rbenzene>rtoluene>rmethanol>rethanol>risopropanol.When the selectivity of CPE is 995%,the yield of CPE(Y) decreased in the order:Ytoluene≈Ybenzene>Yisopropanol>Yethanol>Ymethanol>Ydichloromethane>Ydichloroethane.Increase in benzene amount the yield of CPE increase by suppressing CPD polymerization. The hydrogenation of CPD in benzene (the volume ratio is: CPD∶benzene=2∶25) at 30℃,110×105～123×105Pa of hydrogen , Raney Ni catalyst gave 901% CPE with 995% selectivity.