Li-Ca-Zn-Al-O催化油脂醇解反应  

ALCOHOLYSIS REACTION OF VEGETABLE OIL CATALYZED BY Li-Ca-Zn-Al-O

作　　者：靳福全[1] 

机构地区：[1]太原工业学院化学与化工系,太原030008

出　　处：《石油炼制与化工》2016年第10期17-22,共6页Petroleum Processing and Petrochemicals

基　　金：山西省高校科技开发项目(2010130);山西省高等学校大学生创新创业训练项目(2015449)

摘　　要：以锂、钙、锌、铝的硝酸盐为原料,尿素为沉淀剂,采用沉淀焙烧法制备了Li-Ca-Zn-Al-O复合氧化物催化剂,采用单因素试验考察了制备条件对催化剂活性的影响。制备复合氧化物催化剂的优化条件为:元素配比n(Li)∶n(Ca)∶n(Zn)∶n(Al)=1∶4∶2∶2,反应温度120℃,焙烧温度800℃,焙烧时间7.0h。将优化条件下制备的Li-Ca-Zn-Al-O复合氧化物用于催化蓖麻油和甲醇的醇解反应,在n(甲醇)∶n(蓖麻油)=9∶1、m(催化剂)∶m(蓖麻油)=0.04∶1、搅拌速率550r/min、反应温度65℃、反应时间3h的条件下,蓖麻油转化率可达91.9%。采用Hammett指示剂法、TG、BET及XRD对复合氧化物及其前躯体进行了表征。结果显示:Li-Ca-Zn-Al-O复合氧化物的碱强度为7.2~11.2;Li-Ca-Zn-Al类水滑石在温度升至800℃时质量趋于稳定;Li-Ca-Zn-Al-O复合氧化物催化剂比表面积为25.70m^2/g、孔体积为0.047 74cm^3/g,且主要由CaO及ZnO两种晶体构成。Using nitrates of lithium, calcium, zinc and aluminum as raw materials, urea as precipitating agent, the Li-Ca-Zn-Al-O composite oxide catalysts were prepared by precipitation-calcination method. Effect of preparation conditions on the catalytic activity for alcoholysis is investigated by single factor experiment. The optimal conditions for preparing the optimal catalyst are： the element ratio of n（Li）：n（Ca）：n（Zn）：n（Al） =1：4：2：2, reaction temperature of 120 ℃, calcination temperature of 800 ℃, calcination time of 7.0 h. With Li-Ca-Zn-Al-O catalyst prepared under optimal conditions, the alcoholysis reaction of castor oil and methanol was tested at the conditions of n（methanol）：n（castor）=9：1, m（catalyst）：m（castor oil）=0.04：1, stirring speed of 550 r/min, reaction temperature of 65 ℃, reaction time of 3 h. The castor oil conversion is 91.9%. The optimal catalyst and its precursor were characterized by Hammett indicator method, TG, BET and XRD. The results show that the base strength of Li-Ca-Zn-Al-O composite oxide is in the range of 7.2-11.2, the weight of Li-Ca-Zn-Al with hydrotalcite-like structure is invariable when the calcination temperature is above 800 ℃, proven by TG analysis. The specific surface area of the optimal catalyst is 25.70 m2/g, the pore volume is 0.047 74 cm3/g, and is mainly composed of CaO and ZnO crystals.

关 键 词：复合氧化物 固体碱 催化剂 油脂 醇解 

分 类 号：TQ641[化学工程—精细化工]