文献类型：期刊文献

中文题名：Nd掺杂对Ce基催化剂用于CO_(2)与CH_(3)OH直接合成DMC的影响

英文题名：Effects of Nd doping on direct synthesis of DMC with CO_(2) and CH_(3)OH catalyzed by Ce-based catalysts

作者：沈怡婷[1,2];张海涛[1,2];马宏方[1,2];钱炜鑫[1,2];应卫勇[1,2]

机构：[1]华东理工大学化工学院大型工业反应器工程教育部工程研究中心,上海200237;[2]华东理工大学煤液化气化及高效低碳利用全国重点实验室,上海200237

年份：2025

卷号：50

期号：10

起止页码：36

中文期刊名：低碳化学与化工

外文期刊名：Low-Carbon Chemistry and Chemical Engineering

收录：;北大核心:【北大核心2023】；

基金：国家自然科学基金(22178113);中央高校基本科研业务费专项资金(JKA01231712,JKCA1241202)。

语种：中文

中文关键词：碳酸二甲酯;直接合成;Nd掺杂;Ce基催化剂;二氧化碳;甲醇

外文关键词：dimethyl carbonate;direct synthesis;Nd doping;Ce-based catalysts;carbon dioxide;methanol

摘要：二氧化碳(CO_(2))与甲醇(CH_(3)OH)直接合成碳酸二甲酯(DMC),是目前最具环保优势的DMC合成方法之一。Ce基催化剂常用于CO_(2)与CH_(3)OH直接合成DMC反应,但CeO_(2)存在热稳定性不足和活性位点有限等问题。以六水硝酸钕(NdN3O9·6H_(2)O)作为助剂,采用共沉淀法制备了一系列Nd掺杂Ce基催化剂。催化剂结构经ICP-OES、XRD、HR-TEM和XPS等表征,并研究了催化剂的催化性能。结果表明,适当的Nd掺杂量(质量分数,下同)对优化催化剂的比表面积、氧空位密度和酸碱性位点数量有积极作用。其中,Nd掺杂量为5%的催化剂(5%Nd_(2)O_(3)-CeO_(2))具有最大的氧空位密度、较多的中酸性位点和最多的弱碱性位点。在CH_(3)OH用量为23.74 g、2-氰基吡啶用量为36.44 g、5%Nd_(2)O_(3)-CeO_(2)用量为200 mg、温度为140℃和压力为1.2 MPa的条件下反应2 h,5%Nd_(2)O_(3)-CeO_(2)的CH_(3)OH转化率为27.35%,DMC选择性为77.72%,DMC产量为392.90 mmol/g。在温度为140℃、压力为1.2 MPa、CH_(3)OH用量为23.74 g、5%Nd_(2)O_(3)-CeO_(2)用量为200 mg和反应时间为2 h的条件下,5%Nd_(2)O_(3)-CeO_(2)经过4次循环反应后,其催化性能仍优于CeO_(2)。
The direct synthesis of dimethyl carbonate(DMC)with carbon dioxide(CO_(2))and methanol(CH_(3)OH)is currently one of the most environmentally advantageous methods for DMC production.Ce based catalysts are commonly used in direct synthesis of DMC with CO_(2) and CH_(3)OH,but CeO_(2) suffers from issues such as insufficient thermal stability and limited active sites.Using neodymium nitrate hexahydrate(NdN3O9·6H_(2)O)as the promoter,a series of Nd-doped Ce-based catalysts were prepared by co-precipitation method.The structures of catalysts were characterized by ICP-OES,XRD,HR-TEM,and XPS,etc.,and their catalytic performances were investigated.The results show that the appropriate Nd doping amount(mass fraction,the same below)can positively optimize the catalyst’s specific surface area,oxygen vacancy density and the number of acid-base sites.Among them,the catalyst with Nd doping amount of 5%(5%Nd_(2)O_(3)-CeO_(2))has the highest oxygen vacancy density,more medium-strong acid sites,and the most weak base sites.Under the reaction conditions of CH_(3)OH dosage of 23.74 g,2-cyanopyridine dosage of 36.44 g,5%Nd_(2)O_(3)-CeO_(2) dosage of 200 mg,temperature of 140℃ and pressure of 1.2 MPa,5%the CH_(3)OH conversion rate is 27.35%,DMC selectivity is 77.72%and DMC yield is 392.90 mmol/g catalyzed by 5%Nd_(2)O_(3)-CeO_(2) after reacting for 2 h.After four cycles under the conditions of temperature of 140℃,pressureof 1.2MPa,CH_(3)OHdosageof23.74g,5%Nd_(2)O_(3)-CeO_(2) dosage of 200 mg and reaction time of 2 h,the catalytic performance of 5%Nd_(2)O_(3)-CeO_(2) remains superior to that of CeO_(2).