MOR负载的自还原型双功能催化剂用于催化纤维素氢解制乙二醇的研究

以丝光沸石分子筛(MOR)为载体,以高温生物碳源分解产物H2或CO为还原剂,采用等体积浸渍法制备自还原型双功能催化剂Ni-W/MOR,不经过还原过程直接将其应用于纤维素水相氢解制备低碳乙二醇的研究。考察了催化剂的煅烧温度、活性金属含量配比对纤维素转化率和目标产物收率的影响。结果表明,催化剂的煅烧温度在773 K为宜;XRD表征结果说明,催化剂中活性金属结晶度和晶体的种类与催化剂的配比有关;TEM照片可直观地说明,采用上述方法制备的催化剂中活性金属在载体上具有较好的分散性,粒径均小于20 nm。当Ni、W含量分别为10%和15%,煅烧温度为773 K,反应条件为513 K、5.0 M Pa、2 h时低碳多元醇总收率为56.92%,其中,乙二醇收率为52.30%。

Mordenite supported Ni-W self-reducing bifunctional catalyst for cellulose hydrogenolysis into ethylene glycol

Based on the reducing gases (H₂ and CO) generated from biomass-based carbon at high clacination temperature, self-reducing bifunctional catalyst Ni-W/MOR was prepared by incipient impregnation. This series of catalysts were directly applied to cellulose hydrogenolysis to low carbon polyols in aqueous solution, omitting the catalysts reduction step. The effects of catalysts temperature of the catalyst and weight ratio of active components on conversion of cellulose and yield of target products were investigated. The optimal calcination temperature was 773 K through experimental results. XRD analysis showed that the crystallinity and species of metallic alloys were related to different weight ratios of nickel and tungsten. It was intuitively observed that the active metals showed good dispersion on the surface of MOR through TEM characterization, with particles sizes less than 20 nm. The total yield of low carbon polyols was up to 56.92%, including 52.30% of EG under the reaction condition of 5.0 MPa of H₂ for 2 h reaction time and the calcination temperature of catalysts was 773 K.