【作者】 胡曦； 梁金花； 张锋； 姜岷； 武文良； 任晓乾；

【Author】 HU Xi;LIANG Jinhua;ZHANG Feng;JIANG Min;WU Wenliang;REN Xiaoqian;College of Chemistry and Chemical Engineering,Nanjing Tech University;College of Biotechnology and Pharmaceutical Engineering,Nanjing Tech University;

【机构】 南京工业大学化工学院； 南京工业大学生物与制药工程学院；

【摘要】 以镁铝复合氧化物为载体,通过浸渍、焙烧手段制备了一系列酸碱双功能S/LDO催化剂。采用XRD、SEM、FT-IR、Py-IR及Hammett指示剂等表征方法对催化剂的结构性质、酸碱性质进行了表征。并探讨了催化剂酸碱性质对尿素与1,2-丙二醇合成碳酸丙烯酯反应的影响。酸碱性质表征结果显示,经过硫促改性过程,镁铝复合氧化物酸性明显增强。当过硫酸铵用量达到5wt.%,所得催化剂5wt.%S/LDO酸碱比例较为合适,催化效果较好。本文针对5wt.%S/LDO催化剂在反应条件上做了适当优化,当1,2-丙二醇与尿素的摩尔比为4,5wt.%S/LDO催化剂用量为原料质量的1%,反应温度170oC,反应时间5 h,碳酸丙烯酯收率可达95.5%。更多还原

【Abstract】 A series of acid-base bifunctional S/LDO catalysts was prepared by the processes of impregnation and calcination with calcined hydrotalcite as substrate. The structural properties and acid-base properties were characterized by XRD, SEM, FT-IR, Py-IR and Hammett indicators. Meanwhile, the effect of catalyst’s acid-base properties for the alcoholysis of urea and 1,2-propylene glycol to synthesize propylene carbonate was also investigated. The results of acid-base characterization showed that the acidity of calcined hydrotalcite was enhanced after the sulphur-modified process. The 5wt.%S/LDO catalyst was obtained with appropriate ratio of acidic sites and basic sites when the amount of ammonium persulfate is 5wt.%. The optimization of the reaction condition was n(1,2-propanediol): n(urea)=4: 1, amount of 5wt.%S/LDO catalyst 1%, reaction temperature 170 oC, reaction time 5 h. The yield of PC could reach 95.5%.更多还原