摘要
采用共沉淀法制备了ZIF-8催化剂,利用XRD,FTIR,SEM,TG对催化剂进行了表征,考察了物料比、反应温度、反应时间、催化剂用量等对尿素与1,2-丙二醇(PG)合成碳酸丙烯酯(PC)的影响。实验结果表明,在n(PG)∶n(尿素)=4、催化剂用量(以尿素计)3.3%(w)、反应温度170℃、反应时间3 h的条件下,PC的收率达85.94%;ZIF-8催化剂具有较好的稳定性,重复使用7次,PC的收率仍为77.50%。表征结果显示,催化剂使用前后晶体结构和化学结构未发生改变,但使用后催化剂的晶粒尺寸增大、结晶度提高、晶面缺陷减少,导致反应活性位点减少,这可能是催化剂活性降低的主要原因。
ZIF-8 was prepared by coprecipitation method.It was characterized by XRD,FTIR,SEM and TG.The effects of material ratio,reaction temperature,reaction time and amount of catalyst on the synthesis of propylene carbonate(PC)from urea and 1,2-propylene glycol(PG)were studied by using ZIF-8 as catalyst.The results showed that the yield of PC was 85.94%,when n(PG)∶n(urea)is 4,amount of catalyst is 3.3%(w)(based on urea),reaction temperature is 170℃and reaction time is 3 h.ZIF-8 catalyst had good stability,and the yield of PC was still 77.50%after the catalyst was reused for 7 times.The characterization results showed that the crystal structure and chemical structure of the catalyst didn’t change before and after use,but the increase in crystal size and crystallinity and the decrease in crystal defects led to the reduction in active sites,which may be the main reason for the decrease in catalyst activity.
作者
赵诗雨
贾冰莹
陈学君
刘绍英
白元盛
王公应
Zhao Shiyu;Jia Bingying;Chen Xuejun;Liu Shaoying;Bai Yuansheng;Wang Gongying(Chengdu Institute of Organic Chemistry,Chinese Academy of Sciences,Chengdu Sichuan 610041,China;National Engineering Laboratory for VOCs Pollution Control Material&Technology,University of Chinese Academy of Sciences,Beijing 100049,China;Chengdu Organic Chemicals Co.,Ltd.,Chinese Academy of Sciences,Chengdu Sichuan 610041,China)
出处
《石油化工》
CAS
CSCD
北大核心
2021年第9期879-884,共6页
Petrochemical Technology
基金
四川省区域创新合作项目(2020YFQ0003)。
