混合型 Ni-W 催化剂催化葡萄糖氢解制乙二醇的反应研究

摘要

将一定浓度的水合硝酸镍浸渍于分子筛（SBA-15）上，在500℃下煅烧制得不同 Ni含量的自还原型单金属加氢催化剂（Ni／SBA-15），再与钨基催化剂按质量比10砄15混合，制得混合型双金属 Ni-W 催化剂，将其应用于葡萄糖加氢催化制备乙二醇的反应中，考察了钨基催化剂的种类、用量、Ni／SBA-15加氢催化剂中Ni含量及其用量对葡萄糖的转化率和乙二醇收率的影响。结果表明：加氢催化剂Ni／SBA-15中有金属Ni的存在，且晶体状态与Ni含量有关，钨基催化剂中WO3效果较好；葡萄糖氢解制备乙二醇的较优反应条件为葡萄糖0．5 g，水55 mL，WO30．1 g，Ni质量分数为12％的 Ni／SBA-15加氢催化剂0．15 g，H2压力5．0 MPa，反应温度240℃，反应时间2 h，在此条件下制得的乙二醇收率为26．0％，葡萄糖转化率为99．1％。%A self-reduction monometallic hydrogenation catalyst ( Ni/SBA-15 ) was prepared with different Ni loading by im-pregnating molecular sieve SBA-15 with nickel nitrate hydrate of a specific concentration prior to calcinations at 500 ℃ and was mixed with tungsten-based catalyst at the mass ratio of 10:15 to produce a hybrid bimetallic Ni-W catalyst , which was applied in the reaction system of glucose hydrogenation into ethylene glycol .The effects of the type and amount of tungsten-based catalyst and the Ni loading and amount of Ni/SBA-15 on the conversion rate of glucose and the yield of ethylene glycol were studied .The results showed that metallic Ni existed in Ni/SBA-15 hydrogenation catalyst and its crystal state was related with Ni loading;WO3 provided a satisfying catalysis performance among the tungsten-based catalysts;the yield of ethylene glycol could be 26.0%and the conversion rate of glucose 99.1%under the conditions of 0.5 g glucose, 55 mL water, 0.1 g WO3 , 0.15 g Ni/SBA-15 hy-drogenation catalyst containing 12%Ni by mass fraction, H2 pressure 5.0 MPa, reaction temperature 240℃, reaction time 2 h.