炭化蔗渣负载钌催化剂的制备及其应用研究

摘要

Carbon supported ruthenium catalysts ( Ru/CSB ) were prepared with sugarcane bagasse as raw material by carbonization and impregnation method , which were used in the conversion of glucose to sorbitol .The structures of catalysts were characterized by XRD , SEM and TEM .The effects of reaction conditions on the performance and reusability of catalysts were investigated .Characterization results showed that Ru particles were well dispersed throughout the carbonized sugarcane bagasse ( CSB) .The glucose conversion of 99.41%, sorbitol yield of 98.13% and sorbitol selectivity of 98.71% could be obtained under the conditions of carbonization temperature of sugarcane bagasse 450 ℃, catalyst dosage ( the mass percent of reaction system) 1%, H2 pressure 3 MPa, reaction temperature 120℃, reaction time 2 h.The reusabilities of catalysts were excellent . After using for five times , the dispersity of Ru declined , and the sorbitol yield slightly decreased to 94.80%.%以蔗渣为原料,采用炭化-浸渍法制备碳基钌催化剂(Ru/CSB),并将其应用于催化葡萄糖加氢制备山梨醇.利用XRD、SEM和TEM对催化剂结构进行了表征,并考察了不同反应条件对催化剂性能的影响以及催化剂的重复使用效果.催化剂表征结果显示:活性金属Ru很好地负载在炭化蔗渣(CSB)载体上,且分布均匀.在蔗渣炭化温度为450℃,催化剂用量(以反应体系质量分数计)为1%,氢气压力为3 MPa,反应温度为120℃,反应时间为2 h的条件下,葡萄糖转化率为99.41%,山梨醇得率为98.13%,山梨醇选择性为98.71%.催化剂的重复使用性能较好,在重复使用5次后,Ru的分散度下降,出现团聚现象,山梨醇的得率有略微的下降,为94.80%.