用于蓖麻油甲醇解催化剂KF-MgO/Al_2O_3的制备和表征  

PREPARATION AND CHARACTERIZATION OF KF-MgO/Al_2O_3 FOR CASTOR OIL METHANOLYSIS CATALYST

作　　者：徐鸣[1] Xu Ming(Department of Applied Chemistry,School of Chemical Engineering,Shengli College China University of Petroleum,Dongying 257061,Shandong,China)

机构地区：[1]中国石油大学胜利学院化学工程学院应用化学系,山东东营257061

出　　处：《精细石油化工》2018年第6期6-11,共6页Speciality Petrochemicals

基　　金：国家自然科学基金面上项目(51473028)

摘　　要：为了提高蓖麻油甲醇解反应速率,分别以MgAc_2水溶液、KF水溶液作为浸渍液,Al_2O_3作为载体,采用二次浸渍、二次焙烧的方法制备了KF-MgO/Al_2O_3催化剂。将其用于蓖麻油甲醇解反应,通过正交实验优化的催化剂制备条件为:一次焙烧温度500℃,一次焙烧时间3h,二次焙烧温度450℃,二次焙烧时间5h。利用哈密特指示剂滴定法、TG-DTG(热重-微分热重)、XRD(X射线衍射)、SEM(扫描电镜)、低温N_2吸附-脱附技术对催化剂及其前驱体进行了表征。结果显示:催化剂碱强度在7.2～18.4;催化剂由负载于Al_2O_3载体表面的MgO、KF及反应产物构成;其比表面积为20.40m^2/g、孔体积为0.048 9cm^3/g。该催化剂能有效提高蓖麻油甲醇解反应速率,使蓖麻油转化率在3h内达到98.79%。In order to increase the methanolysis reaction rate of castor oil,KF-MgO/Al2O3 catalyst was prepared by using MgAc2 aqueous solution and KF aqueous solution as the impregnation liquid and Al2O3 as the carrier by secondary impregnation and secondary calcination.The catalyst was used for the methanolysis reaction of castor oil.The preparation conditions of the catalyst optimized by orthogonal test were as follows:primary calcination temperature 500℃,primary calcination time 3h, secondary calcination temperature 450℃,and secondary calcination time 5h.The catalyst and its precursors were characterized by Hammett indicator titration,TG-DTG (thermogravimetry-differential thermogravimetry),XRD (X-ray diffraction),SEM (scanning electron microscopy)and low temperature N2 adsorption-desorption technique.The results showed that the catalyst alkali strength ranged from 7.2-18.4;the catalyst consisted of MgO,KF and reaction products supported on the surface of Al2O3support;its specific surface area was 20.40m2/g,and the pore volume was 0.0489cm3/g. The catalyst can effectively increase the methanolysis reaction rate of castor oil,and the conversion rate of castor oil reaches 98.79% within 3 hours.

关 键 词：固体碱 催化剂 蓖麻油 生物柴油 

分 类 号：O643.36[理学—物理化学]