Li-Ca-Mg-Al-O固体碱催化制备生物柴油  

PREPARATION OF BIODIESEL CATALYZED BY Li-Ca-Mg-Al-O SOLID BASE

作　　者：王春艳[1] 

机构地区：[1]承德石油高等专科学校,河北承德067000

出　　处：《精细石油化工》2017年第1期11-16,共6页Speciality Petrochemicals

摘　　要：以锂、钙、镁、铝的硝酸盐为原料,以尿素为沉淀剂,采用沉淀焙烧的方法制备了Li-Ca-Mg-Al-O固体碱催化剂。采用单因素实验考察了制备条件对催化剂活性的影响,得到制备优化条件为:元素配比n(Li)∶n(Ca)∶n(Mg)∶n(Al)=1∶2∶1∶1,焙烧温度800℃,焙烧时间6.5h。将优化条件下制备的Li-Ca-Mg-AlO固体碱用于催化蓖麻油和甲醇的酯交换反应,在n(醇)∶n(油)=9,m(催化剂)∶m(油)=0.04,搅拌速率为550r/min,反应温度为65℃,反应时间为3h的条件下,蓖麻油转化率可达85.7%。采用Hammett指示剂滴定法、TG、BET、XRD及SEM对催化剂及其前驱体进行了表征。结果表明:Li-Ca-Mg-Al-O固体碱的碱强度为7.2~11.2;Li-Ca-Mg-Al类水滑石在温度超过800℃后质量不再随温度升高而变化;Li-Ca-Mg-Al-O固体碱催化剂比表面积为11.93m^2/g、孔容为0.031 7cm^3/g,主要由CaO、MgO及Al_2O_3三种晶体组成。With Lithium,calcium,magnesium,aluminum nitrate as the raw material,urea as precipitating agent,the Li-Ca-Mg-Al-O solid base catalyst was prepared by precipitation calcination method.Effects of preparation conditions on the catalytic activity were investigated by single factor experiment.The optimum condition found used for preparing the solid base catalyst was the element ratio of n（Li）∶n（Ca）∶n（Mg）∶n（Al）=1∶2∶1∶1,calcining temperature of 800 ℃,calcination time of 6.5h.Using the Li-Ca-Mg-Al-O solid base prepared under optimum condition as the catalyst of ester exchange reaction of castor oil and methanol,under the conditions of n（alcohol）∶n（oil）=9,m（catalyst）∶m（oil）=0.04,stirring rate of 550r/min,reaction temperature of 65 ℃,reaction time of 3h,the castor oil conversion was 85.7%.The catalyst and its precursor were characterized by Hammett indicator titration,TG,BET,XRD and SEM.The results showed that：the base strength of Li-CaMg-Al-O solid base was 7.2-11.2;the mass of Li-Ca-Mg-Al HTLcs changes no longer with increasing temperature over 800℃;specific surface area of the Li-Ca-Mg-Al-O solid base catalyst is 11.93m-2/g,pore volume was 0.031 7cm-3/g,and was mainly composed of CaO,MgO and Al2O3 three kinds of crystals.

关 键 词：复合氧化物 固体碱 催化剂 油脂 生物柴油 

分 类 号：TE667[石油与天然气工程—油气加工工程]