权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Synthesis of Dimethyl Carbonate Catalyzed by Potassium Salt of Weak Acid-on-Catabon and Related Systems.

弱酸钾盐催化合成碳酸二甲酯及相关体系。

基本信息

批准号：
10650771
负责人：
HAYASHI Hiromu
金额：
$ 1.6万
依托单位：
The University of Tokushima
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1998
资助国家：
日本
起止时间：
1998 至 1999
项目状态：
已结题

项目摘要

To develop a new process for the synthesis of dimethyl carbonate, base-catalyzed transesterification of ethylene carbonate-methanol system has been studied. The route is of interest, as ethylene carbonate could be obtained in a low cost through reaction of ethylene oxide with carbon dioxide. Basic catalysts such as magnesia and hydrotalcites are effective for transesterification, but a trace of moisture may cause to decompose carbonate to carbon dioxide, which unfortunately deactivates the catalyst. In the present work, potassium salts of various acids such as carbonate, dihydrogenphosphate and acetate were examined. The treaction could be carried out without catalyst degeneration.Recycling use of ethylene glycol which accumulates in the transesterification of ethylene carbonate-alcohol system is an important problem for practical applications. Thus oxidative carbonylation of ethylene glycol to ethylene carbonate has been studied in the present work. Cuprous chloride dissolves into ethylene glycol by absorption of molecular oxygen to give a green solution of cupric glycoxide chloride. The copper(II) complex was resuced by carbon monoxide under pressure of 10 atm at 50-80℃ to afford ethylene carbonate in high yield. The concentration of ethylene carbonate in liquid phase increased linearly with time by continuous absorptions of mixed gas of OィイD22ィエD2/CO=1/2 under pressure of 15 kg/cmィイD12ィエD1. The yield of ethylene carbonate of 739% based on CuCl charged was obtained at 50℃ for 4h, signifying the oxidative carbonylation catalysis through redox cycle of copper-glycoxide chloride.

为开发碳酸二甲酯的合成新工艺，对碱催化碳酸乙烯酯-甲醇体系酯交换反应进行了研究。该路线是令人感兴趣的，因为碳酸亚乙酯可以通过环氧乙烷与二氧化碳的反应以低成本获得。碱性催化剂如氧化镁和水滑石对于酯交换是有效的，但是微量的水分可能导致碳酸盐分解成二氧化碳，这不幸地使催化剂失活。在目前的工作中，各种酸的钾盐，如碳酸钾，磷酸二氢钾和乙酸钾进行了检查。碳酸乙烯酯-醇体系酯交换反应中积累的乙二醇的回收利用是实际应用中的一个重要问题。因此，本文对乙二醇氧化羰基化合成碳酸亚乙酯进行了研究。氯化亚铜通过吸收分子氧而溶解于乙二醇中，得到绿色的羟基氧化铜氯化物溶液。在50-80℃、10个大气压下，用一氧化碳还原铜（Ⅱ）络合物，高产率地得到碳酸亚乙酯。在压力为15 kg/cm × 12 × 1在50℃下反应4 h，以CuCl计，碳酸乙烯酯的收率可达739%，表明铜-氯乙醇氧化还原循环催化氧化羰基化反应。