文档介绍：。啦删⑧天洋大尊中国近代第一所大学硕士学位论文一■啊●■嘲|强■■■■¨r___ 学科亏业: 些主工艺作者姓名:堑堂指导敦师:型塞重型墼堂 2006年1月中文摘要在乙酸乙酯的工业化合成路线中,乙醇一步合成法由于成本低、设备腐蚀小以及无毒性等优点,被认为是最有前景的乙酸乙酯制备方法。本文开发了一种全新的基于MoS2/C催化剂的乙醇一步法合成乙酸乙酯的工艺。本文研究了助催化剂铜的添加对催化剂性能的影响,对反应工艺条件进行了优化,并对该催化过程的反应机理进行了讨论。研究结果表明,助催化剂铜的添加能提高乙酸乙酯的选择性,并可降低乙醛的选择性。铜的负载量为Cu/MoS2=5%(铜与MoS2的质量比)时乙酸乙酯的选择性较高,达到48%。助剂的添加顺序也对催化剂性能有比较明显的影响, 先负载铜的催化剂催化活性较高。对添加助剂的催化剂的XRD表征发现,/$(摩尔比)物相。对工艺条件的研究表明,反应温度为290 ℃,,催化剂有较高的催化活性,乙酸乙酯选择性为48%, 乙醇转化率为86%。通过乙酸乙酯生成机理的研究发现,乙酸乙酯的生成是由两个脱氢步骤构成的。第一步为乙醇脱氢生成乙醛,第二步为乙醇和乙醛加成脱氢生成乙酸乙酯。实验结果表明,纯乙醛在该催化剂上不发生生成乙酸乙酯的反应,故否定了乙醛缩合和乙醛歧化生成乙酸乙酯的反应机理。本文还对主要副产物烯烃的生成过程进行了研究,结果表明,主要副产物乙烯和丙烯,其主要生成来源为乙醇,由乙醛向乙烯或丙烯的转化很难发生。关键词: MoS2/C催化剂铜助剂乙醇乙酸乙酯脉冲反应 ABSTRACT Among thedifferent technical routes forethyl acetate production,the direct synthesis from ethanol has drawn more and more attention because ofitsless corrosion,low toxicityand cost. Inthiswork,the novel MoS2/C supported catalystand the relatedtechnology for one-step synthesis ofethyl acetate fzomethanol were promoter effect of Cu on theperformance ofcatalyst technological conditions wereoptimized and thepossible reactionmechanism Wasdiscussed. The resultsshowed thatthe addition ofCu couldimprove the selectivity of ethylacetate(EA)and inhabited theformation the Culoading was 5%based OntheMoS2 weight,the selactivity forEAcould reach to48%.The adding sequences ofpromoter may alsoinfluence prior addifion of Cucould enhance the XRD characteristic ofthecatalyst showed thatthe nOW Cu-Mo·S phase withmolar ratioof :6:. Under theoptimized reaction conditions oftemperature 290112 and ethanol space ‘。theethanol conversion Was86%and EAselectivity was 48%. The study on theformationmechanism ofEA showed thatthere was two steps dehydrogenation inthe firststep was ethanol dehydrogenation to acetaldehyde,and thesecond one was theaddition-dehydrogenation ofethanol wi