PREPARATION OF ETHYLENE GLYCOL ACETATE THROUGH CATALYTIC OXIDATION OF ETHYLENE——ONE-STEP PROCESS WITH SIMULTANEOUS INTRODUCTION OF OXYGEN AND ETHYLENE INTO A Pd-Cu CATALYTIC SOLUTION

Ethylene glycol acetate can be prepared from ethylene by employing PdCl_2-CuCl_2-Cu(OAc)_2 in anacetic acid solution,usually involves two steps-acetoxylation and the regeneration of catalyst.In thispaper,a one-step process has been studied with oxygen and ethylene introduced simultaneously in a singlereactor.It was observed that there must be enough partial pressure of oxygen to oxidize Cu~+ to Cu~(2+)by keeping oxygen content at 8-10% in the raw binary gas mixture of oxygen and ethylene,whereby theactivity of the catalytic system could be maintained without formaton of CuCl residue.By using nitrogen as a diluent,the ratio of O_2/C_2H_2 could be kept in the non-explosive range.Itis claimed that 95% of the converted ethylene from the feed gas exists as ethylene glycol monoacetateand diacetate.     

乙烯直接氧化制乙二醇酯

开发了一种均相Pd-Cu催化系统,可以在5kg/cm~2左右,65℃的条件下进行反应。有效酯的选择性在90％以上。根据试验计算出每生产一吨乙二醇消耗乙烯0.5吨,乙烯有效利用率在90％以上。反应条件缓和,不含泥渣。由于利用反应-萃取方法提取产物,降低了过程的能耗,而且在本法中乙酰氧基化反应和催化剂再生同时进行,是一项新工艺流程。     

乙烯直接氧化制备乙二醇醋酸酯的研究——氧和乙烯同时进入Pd-Cu催化反应液一步法的工艺研究

用PdCl_2-CuCl_2-Cu(OAc)_2醋酸溶液的催化体系由乙烯制备乙二醇醋酸酯,催化过程分乙酰氧基化及催化剂再生二步.本文作了进一步的研究.即将氧和乙烯同时送入反应器,使乙酰氧基化反应和催化剂再生过程为一步过程.研究证明:当采用氧及乙烯作原料气时,在双组份中氧含量8—10%时,才有足够的氧分压,能使Cu~+氧化成Cu~(?),从而保持催化系统的活性,因而基本上在催化体系中无CuCl的残渣生成.并研究了以N_2作为添加组成,可以使O_2/C_2H_4处于非爆炸范围,所得结果,原料气转化的乙烯中有95%生成乙二醇单醋酸酯和乙二醇双醋酸酯.