聚乙二醇对旋转填充床制备La_(0.5)Pb_(0.5)MnO_3载体的影响  

Effects of polyethylene glycol on preparation of La_(0.5)Pb_(0.5)MnO_3 in rotating packed bed

作　　者：鲁超[1] 金放[1] 袁华[1] 杜治平[1] 吴元欣[1] 

机构地区：[1]武汉工程大学化工与制药学院绿色化工过程省部共建教育部重点实验室湖北省新型反应器与绿色化学工艺重点实验室,湖北武汉430073

出　　处：《化学工程》2010年第9期60-64,共5页Chemical Engineering(China)

基　　金：国家自然科学基金重点项目(20936003);湖北省自然科学基金重点项目(2008CDA009)

摘　　要：采用旋转填充床液液相共沉淀法制备了钙钛矿复合氧化物La0.5Pb0.5MnO3,以其作为载体制备了0.5%Pd(质量分数)/La0.5Pb0.5MnO3催化剂合成碳酸二苯酯。为了提高催化剂的活性,采用聚乙二醇(PEG)为分散剂对载体表面改性,通过XRD,SEM,BET手段对其物性进行表征,并对催化剂进行了活性评价。结果表明:PEG良好的空间位阻效应可以增加载体的分散度和比表面积,提高催化剂的活性。PEG10 000浓度为0.001 5 mol/L时效果最佳,载体比表面积达53.73 m2/g。反应温度65℃,总压5 MPa,p(CO)∶p(O2)=94∶6,反应3 h,DPC收率达13.30%。反应9 h,该条件下DPC收率可达21.90%。The La0.5Pb0.5MnO3 perovskite composite oxides were prepared as the carrier of the 0.5%Pd（mass fraction）/La0.5Pb0.5MnO3 catalyst for the synthesis of diphenyl carbonate（DPC） by co-precipitation method in rotating packed bed.In order to enhance the catalyst activity,polyethylene glycol（PEG） was used as dispersing agent for modifying the carrier surface.The property of PEG was characterized by XRD,SEM,BET,and the activity of catalyst was evaluated.The results show that the steric effect of PEG can enhance the dispersion and specific surface area of supports,which results in the increment of the yield of DPC.After the addition of PEG in the optimal conditions,i.e.relative molecular mass 10 000,concentration 0.001 5 mol/L,the specific surface area of support can achieve 53.73 m2/g.With the reaction temperature 65 ℃,total pressure 5 MPa,p（CO） ∶ p（O2）=94 ∶6,reaction time 3 h,the yield of DPC can reach 13.30%.Reaction time 9 h,the yield of DPC can reach 21.90%.

关 键 词：碳酸二苯酯 旋转填充床 聚乙二醇 

分 类 号：TQ032[化学工程]