摘要
采用共沸除氯工艺制备SO42-/SnO2-Nb2O5固体超强酸,该方法引入共沸蒸馏,以正丁醇和无水乙醇为溶剂,锡盐醇溶液滴加氨水前除去其中结晶水再除氯离子,免去抽滤除氯步骤,缩短了催化剂制备时间。将制备的SO42-/SnO2-Nb2O5用于催化α-蒎烯的异构化反应,考察催化剂制备条件对催化剂活性的影响,采用FT-IR,XRD,TG-DTA等对催化剂的物化性质进行表征,并与沉淀法、sol-gel法制备的催化剂进行对比。结果表明:催化剂最佳制备条件为Nb2O5加入量为SnO2质量的25%、浸渍液硫酸浓度0.5 mol/L、焙烧温度500℃、焙烧时间2 h,将该条件下制备的SO42-/SnO2-Nb2O5应用于催化α-蒎烯异构化反应时,α-蒎烯完全转化,莰烯选择性为66.49%;与沉淀法、sol-gel法相比,相同条件下共沸除氯法制备的催化剂较好。
SO42/SnO2-Nb2O5 solid superacid catalyst was prepared by azeotropic dechlorination method,using n-butanol and anhydrous alcohol as solvents,a filtration step could be omitted,and thus the catalyst preparation time was much shortened.The prepared catalyst was characterized by XRD,FT-IR,TG-DTA and its catalytic performance was evaluated using isomerization of α-pinene as probe reaction.Test results showed that the optimum preparation conditions of SO42/SnO2-Nb2O5 solid superacid catalyst were as follows： a Nb2O5/SnO 2 mass ratio of 0.25,the concentration of impregnating sulfuric acid solution was 0.50 mol/L and calcined at 500 ℃ for 2.0 h;catalyst prepared under such conditions exhibited good catalytic performance in isomerization of α-pinene,the conversion of α-pinene and selectivity of camphene was 100% and 66.49%,respectively.Compared with other preparation methods,such as precipitation and sol-gel methods,catalyst prepared by azeotropic dechlorination method was better.
出处
《石油炼制与化工》
CAS
CSCD
北大核心
2012年第8期68-72,共5页
Petroleum Processing and Petrochemicals
基金
肇庆市科技计划项目(批准号:2009G013)
肇庆市科技创新计划项目(批准号:2011G28)资助
关键词
共沸除氯
固体超强酸
五氧化二铌
Α-蒎烯
异构化
制备
表征
azeotropic dechlorination
solid superacid
niobium pentaoxide
α-pinene
isomerization
preparation
characterization
