摘要
对KNO3/MCM-48用于丙醇和碳酸二甲酯进行酯交换合成碳酸二丙酯的催化性能进行了考察.用X射线衍射(XRD)、红外光谱(IR)和X射线荧光法研究了催化剂的结构特征和表面性质.XRD结果表明,随着K负载量的增加,载体特征峰强度逐渐减弱,但仍保留MCM-48的晶体结构.随着焙烧温度的升高,KNO3逐渐分解成K2O.分别考察了活性组分负载量、焙烧温度、焙烧时间和催化剂的用量以及反应时间对反应的影响.结果表明,KNO3/MCM-48催化剂对碳酸二丙酯的合成具有很高的催化活性.在反应温度363 K,反应时间6 h,催化剂用量5%,丙醇与碳酸二甲酯摩尔比为4的条件下,碳酸二甲酯的转化率可达99.9%,产物碳酸二丙酯选择性93.4%,产率93.3%.
The catalytic performance of KNO3/MCM-48 catalysts for the synthesis of dipropyl carbonate （DPC） by transesterification of dimethyl carbonate （DMC） and propanol was investigated. The catalysts were characterized by X-ray diffraction （XRD）, FT-IR spectroscopy, N2 adsorption and X-ray fluorescence. XRD results indicated that the intensity of characteristic peaks of MCM-48 was gradually reduced with the increase of K loading in KNOa/MCM-48, but the MCM-48 structure was still remained. IR spectra showed that KNO3 was gradually decomposed into K20 with increasing calcination temperature. The relative high catalytic activity and selectivity were obtained by changing the K loading and the reaction conditions. Under the optimized reaction conditions of reaction temperature 363 K, reaction time 6 h, catalyst dosage 5 % and propanol/DMC molar ratio 4, the conversion of DMC was about 99.9 %, the selectivity for DPC was 93.4 %, and the yield of DPC reached 93.3% by using a catalyst with 15% K loading and calcined at 823 K.
出处
《催化学报》
SCIE
CAS
CSCD
北大核心
2005年第11期965-970,共6页
基金
国家重大基础研究前期研究资助项目(2003CCA03200)
关键词
硝酸钾
MCM-48分子筛
负载型催化剂
碳酸二甲酯
酯交换
碳酸二丙酯
potassium nitrate, MCM-48 molecular sieve, supported catalyst, dimethyl carbonate, transesterification, dipropyl carbonate
