固体酸SO_4^(2-)/TiO_2催化葡萄糖制备乙酰丙酸甲酯  

Solid Acid SO_4^(2-)/TiO_2 Catalyzed Glucose Conversion to Methyl Levulinate

作　　者：曾珊珊[1] 林鹿[1] 彭林才[1] 

机构地区：[1]华南理工大学制浆造纸工程国家重点实验室,广东广州510640

出　　处：《现代食品科技》2011年第7期783-787,共5页Modern Food Science and Technology

基　　金：国家自然科学基金(50776035;U0733001);国家科技支撑计划项目(2007BAD34B01);973计划项目(2010CB732201)

摘　　要：通过沉淀-浸渍法制备了一系列不同焙烧温度的SO42-/TiO2固体酸催化剂,用于在甲醇中催化转化葡萄糖制备乙酰丙酸甲酯,探讨了不同反应条件及催化剂重复使用次数对乙酰丙酸甲酯得率的影响,并利用XRD和NH3-TPD对使用前后的催化剂的结构和酸性进行了表征。实验结果表明:500℃焙烧3 h的催化剂,在催化剂用量为2.5 wt%,反应温度为200℃的条件下反应2 h,乙酰丙酸甲酯得率达35 mol%。第一次回收的催化剂焙烧后使用催化性能明显下降,而之后的多次重复使用能保持较稳定的反应活性。XRD和NH3-TPD分析结果表明,使用后的催化剂的晶型结构仍保留,酸强度和总酸量随重复使用次数增加而逐渐降低。A series of SO42-/TiO2 solid acid catalysts were prepared at different calcination temperatures by the precipitation and impregnation method.The catalysts were used to catalyze glucose conversion to methyl levulinate in methanol.The influence of different reaction conditions and catalyst reuse cycle on methyl levulinate yield was investigated.The surfaces structure and acidity changes of the fresh and used catalysts were characterized by XRD and NH3-TPD.Experimental results showed that methyl levulinate yield of 35 mol% could be obtained under the conditions of the catalyst calcined at 500 ℃ for 3 h,catalyst dosage 2.5 wt%,reaction temperature 200 ℃and reaction time 2 h.The catalytic activity decreased obviously for the first recovered catalyst after calcination,while there were relatively stable reaction activities in the following several reuse.The XRD and NH3-TPD results illustrated that the catalyst crystallization structure was preserved after reuse,the acid strength and total amounts of acid gradually decreased with increasing reuse times.

关 键 词：葡萄糖 乙酰丙酸甲酯 SO42-/TiO2 催化 

分 类 号：TQ225.241[化学工程—有机化工]