硅钨杂多酸制备表征及催化酯化反应制备生物-有色金属科学与工程.DOC

硅钨杂多酸制备、表征及催化酯化反应生物柴油活性研究舒庆*程文辉江西理工大学冶金与化学工程学院，赣州，341000摘要：硝酸酸化乙醚萃取法制备硅钨杂多酸催化剂(SEM)、红外光谱FTIR)、X(XRD)、程序升温脱附NH3-TPD)、热重分析(TG)等手段对催化剂进行了表征，并以甲醇和油酸为反应物，研究了所制备的硅钨酸，催化剂用量、反应时间、反应温度酯化反应产品收率的影响.结果表明：3:2，催化剂用量为反应物总质量的1.4%反应时间为3.5反应温度为65C时，油酸甲酯的收率为96.45 wt% 关键词：硅钨酸；酯化反应；Studies on the preparation, characterization and catalytic activity test with oleic acid esterification of silicotungstic heteropoly acid SHU Qing, LIU Bao, CHAO Zhi-cong, CHEN Tian-yu, CHENG Wen-hui, (School of Metallurgy and Chemical Engineering, Jiangxi University of Science and Technology, Ganzhou 341000, Jiangxi, China) Abstract: The nitric acid acidification method incorporated with an ether extraction technique was used to prepare a silicotungstic heteropoly acid catalyst in this study. The resulting catalyst was characterized by scanning electron microscopy (SEM), infrared spectroscopy (FTIR), powder X-ray diffraction (XRD), temperature programmed desorption of ammonia(NH3-TPD) and thermogravimetric analysis (TG). The catalytic activity of the silicotungstic heteropoly acid catalyst was studied from the esterification reaction of oleic acid and methanol. The syntheses conditions with respect to catalytic activities have been optimized individually, including the mass ratio of methanol to oleic acid, as well as the mass ratio of catalyst to reactants, reaction time and reaction temperature. Results shown when the mass ratio of methanol to oleic acid was 3:2, mass ratio of catalyst to reactants was 1.4%, reaction time 3.5 h and reaction temperature was 65oC, a yield of methyl oleate 96.45wt% was obtained from this optimal reaction condition. Key words: Silicotungstic acid; Esterification reaction; Catalytic activity 0 前 言 近年来，为了缓解石油短缺和环境保护带来的巨大压力，使得清洁替代燃料的开发和应用步伐大为加快.在这些替代燃料中，具有环境友好和可再生等优点的生物柴油，已经受到了国内外的广泛关注.大力开发生物柴油这一可再生清洁燃料，是解决能源危机、减少环境污染、走可持续发展道路的重要途径.我国能源植物油资源种类丰富多样，可作为生物柴油生产原料的有麻疯果油、桐籽油、大豆油、蓖麻籽油、棉籽油等.如能加快这些能源植物油作为生物柴油生产原料的综合利用开发步伐，不仅可显著促进区域经济的发展，而且也将对我国新能源战略的实施，发挥重要作用[-4]. 生物柴油的主要成分是长链脂肪酸单酯，其可由上述能