摘要:本文使用浸渍法制备了负载型的CuO/MCM-41和CuO/MCM-48催化剂,用掺杂法制备了Cu-MCM-41和Cu-MCM-48催化剂,通过XRD、SEM对合成的催化剂进行表征,并在选择性催化氧化二甲氧基甲烷(DMM)合成碳酸二甲酯(DMC)的反应中评价其催化活性。结果表明:选用不同的方法制备含有铜物种的催化剂时,当介孔分子筛中含有较丰富的Si-OH,有利于其与Cu物种之间产生较强的相互作用,抑制铜物种的聚集,而且有利于催化氧化DMM合成DMC的有效活性组分Cu-O-Si-O的生成。43434
毕业论文关键词:负载;催化剂;DMC
Study on Synthesis of Dimethyl Carbonate by Selective Oxidation Dimethoxy Methane by Supported Copper-Based Catalyst
Abstract: In this paper, the supported catalysts of CuO/MCM-41 and CuO/MCM-48 were prepared by impregnation method, and the catalysts of Cu-MCM-41 and Cu-MCM-48 were prepared by doping method. The samples were characterized by XRD, SEM, and their catalytic activities were evaluated in the reaction of the synthesis of DMC by selective oxidation of DMM. The results showed that the catalysts containing copper species were prepared in different methods, when the mesoporous molecular sieves contained rich Si-OH, it was conducive to produce the strong interaction between Si-OH and Cu species, and which inhabited the migration of Cu species. However, it was benefit to the formation of active components of Cu-O-Si-O.
Key Words: Load; Catalyst; DMC
目 录
摘 要 1
引 言 1
1 实验部分 3
1.1 试剂和仪器 3
1.2 实验方法 3
2 结果与讨论 5
2.1催化剂的XRD分析 5
2.2催化剂的SEM分析 6
2.3催化剂的催化活性分析 7
3 结 论 9
参考文献 10
致 谢 12
负载型铜基催化剂催化氧化二甲氧基甲烷合成碳酸二甲酯的探究
引 言
碳酸二甲酯(Dimethyl Carbonate, DMC)分子式为CH3O-CO-OCH3,常温下是一种无色透明的液体,略有刺激性气,具有与水相近的物性,沸点为90.2 ℃,熔点为4 ℃,黏度为0.644 mPa·s,由于它的低粘度使其可以作为锂离子电池的电解液[1,2]。DMC难溶于水,但可以与有机溶剂如醇、醚等任意比例混合,是一种优良的溶剂[3]。DMC有很高的含氧量(53.3 %),可以代替甲基叔丁醚(MTBE)作汽油添加剂[4]。此外,由于DMC分子结构式中含有甲基、甲氧基、和羰基等多种官能团,可以代替剧毒的光气(COCl2)、氯甲烷、硫酸二甲酯等进行羰基化、甲基化、甲酯化等反应,广泛应用在医药、农药、染料、润滑油添加剂、食品添加剂等的生产中[5-10],因此DMC被誉为21世纪绿色有机合成“新基石”[11]。
目前工业合成DMC的主要方法有甲醇光气法、酯交换法、甲醇氧化羰基化法等[12]。
1)甲醇光气法[13]:利用甲醇和光气反应生成氯甲酸甲酯,氯甲酸甲酯再与甲醇反应得DMC。
COCl2 + CH3OH → ClCOOCH3 + HCl
ClCOOCH3 + CH3OH → (CH3O)2CO + HCl
该工艺原料光气有毒,并且反应的副产物HCl对设备有强烈的腐蚀性,此法已逐渐被淘汰。
2)酯交换法[14]:由碳酸乙(丙)烯酯与甲醇反应制取DMC。
C2H6O3(PC) + 2CH3OH → (CH3O)2CO + CH3CHOHCH2OH