CIESC Journal

• 工业催化 • 上一篇    下一篇

Cu掺杂的Mg-Al类水滑石的制备、表征及其催化性能

刘 媛   

  1. 常州工程职业技术学院化学工程技术系,江苏 常州 213164
  • 出版日期:2011-11-05 发布日期:2011-11-21

Preparation and characterization of Cu-doped Mg-Al hydrotalcites and their catalytic performances

LIU Yuan   

  1. Department of Chemical Engineering,Changzhou Institute of Engineering Technology,Changzhou 213164,Jiangsu,China
  • Online:2011-11-05 Published:2011-11-21

摘要:

采用浸渍法制备了Cu掺杂的镁铝水滑石类化合物Cu/HT,经过400 焙烧得到Cu掺杂的镁铝复合金属氧化物Cu/ Mg-Al LDO,利用X射线衍射(XRD)、扫描电镜(SEM)、热重分析(TG)、N2吸附-脱附等技术对催化剂的结构进行了表征。研究了其对尿素与1,2-丙二醇合成碳酸丙烯酯的催化性能。考察了Cu掺杂量、镁铝比、不同催化剂载体等催化剂制备条件对催化剂活性的影响,同时考察了催化剂的再生性能。结果表明,当Cu掺杂量为1%、镁铝比摩尔为31时的Cu/Mg-Al LDO3)对尿素与1,2-丙二醇合成碳酸丙烯酯具有比较好的催化活性,在170 1,2-丙二醇与尿素的摩尔比为41、催化剂用量为原料总质量的1%、反应3 h时,碳酸丙烯酯的收率达到96.1%,且催化剂经4次再生重复使用,催化活性稳定。

Abstract:

Cu-doped Mg-Al layered double oxides were obtained through calcination at 400 ℃ from the corresponding Cu-doped Mg-Al hydrotalcitewhich was prepared by wetness impregnation. The structural information of Cu/LDO catalysts was characterized by XRDSEMTG and nitrogen-adsorption/desorption techniques. Their catalytic activities were studied in the synthesis of propylene carbonate from urea and 1,2-propylene glycol. The influences of Cu doping amountmole ratio of Mg-Al and different supports were investigated. The regeneration performance of catalysts was also studied. The results indicate that the combination of 1% Cu loading31 MgAl mole ratioCu/Mg-Al LDO3gives much higher activity in propylene carbonate synthesis. Under the reaction condition of 1% Cu/ Mg-Al LDO3n(1,2-propylene glycol)n(urea)= 41reaction temperature of 170 and reaction time of 3 hthe yield of propylene carbonate reaches 96.1%. In a set of reuse experimentsthere is almost no reduction on the catalytic activity.