固体酸WO3/ZrO2催化果糖脱水合成5-羟甲基糠醛

摘要

用共沉淀-热回流处理法制备了系列WO3/ZrO2固体酸催化剂，通过调节W与Zr的摩尔比优化其对果糖脱水制备5-羟甲基糠醛（5-HMF）的催化活性。利用X射线衍射（XRD）、N2吸脱附、氨气程序升温脱附（NH3-TPD）对材料的结构和酸性质进行了表征，并在以二甲基亚砜（DMSO）为溶剂、果糖为原料的催化体系中，考察催化剂的用量、反应时间、反应温度等对5-HMF收率的影响。研究发现，热回流处理大大增加了样品的比表面积，增强了样品的酸强度，当n(W)∶n(Zr)=0.1∶1时，样品比表面积最大，催化活性最好，以其为催化剂，在130℃下反应3 h条件下，5-HMF收率最高可达80.29%。%Catalytic dehydration of fructose to 5-hydroxymethylfurfural (5-HMF) was studied and improved by synthesizing series of solid acid catalyst WO3/ZrO2 with different mole ratio of W to Zr using co-precipitation with hot reflux method. The structure and properties of the catalysts thus synthesized were investigated by X-ray diffraction(XRD),N2 sorption,temperature -programmed desorption of (NH3-TPD),and then the influence of temperature,mass ration of fructose/catalyst and reaction time on the yield of 5-HMF from fructose were studied in dimethyl sulfoxide. These studies showed that specific surface area and acid strength of the catalysts were increased greatly by hot reflux method,and an optimized 5-HMF yield of 80.29%was obtained with 3 h at 130 ℃ in the presence of the sample WO3/ZrO2 with W-Zr mole ratio of 0.1∶1,which had a largest specific surface area and best catalytic activity.