制备条件对氧化铁催化合成碳酸二甲酯反应性能的影响  

Influence of preparation conditions on catalytic properties of iron oxide for synthesis of dimethyl carbonate

作　　者：陈红萍[1,2] 刘广环[1] 梁英华[1] 赵新强[2] 

机构地区：[1]河北联合大学化学工程学院,河北唐山063000 [2]河北工业大学化工学院,天津300130

出　　处：《天然气化工—C1化学与化工》2015年第1期48-55,共8页Natural Gas Chemical Industry

摘　　要：采用沉淀法制备了氧化铁催化剂并对其进行TG/DTA,XRD、N2吸附/脱附、SEM、TEM和FTIR表征,考察了沉淀剂、溶液Fe3+浓度、陈化时间和焙烧温度对其形貌及催化甲醇与CO2直接合成碳酸二甲酯(DMC)反应性能的影响。结果表明,以氨水作沉淀剂,溶液中Fe3+浓度为0.625mol/L,陈化时间12h,焙烧温度为350℃时,氧化铁催化活性最高。均匀分布的纳米颗粒、较大比表面积和完整的α-Fe2O3晶型是其催化活性高的主要原因。通过5次重复使用,催化活性略有降低。在体系中加入N,N-二环己基碳二亚胺(DCC)脱水剂,可显著提高DMC收率。Iron oxide was prepared by means of precipitation method and characterized by TG/DTA, XRD, SEM, TEM, BET and FTIR. The effect of preparation conditions such as the kind of precipitant, Fe3 ＋solution concentration, aging time and calcination temperature on Fe2O3 morphology and catalytic performances for the synthesis of dimethyl carbonate（DMC） from methanol and CO2 was investigated. The results showed that the best catalytic performances was found over the iron oxide prepared under the condition of ammonia as precipitation, Fe3 ＋solution concentration of 0.625mol/L, aging time of 12 h, calcinating temperature of 350℃. A uniform distribution of the nanoparticles, larger spicific surface area and the complete α-Fe2O3 crystal form were the main reasons for the high catalytic activity. The iron oxide was used for five runs and its catalytic performances only decreased a little. In addition,N,N＇-dicyclohexyl carbodiimide（DCC） as a dehydrating agent could increase the yield of DMC significantly.

关 键 词：氧化铁 制备条件 碳酸二甲酯 合成 甲醇 二氧化碳 

分 类 号：O643[理学—物理化学] TQ426[理学—化学]