摘要
采用无有机模板剂一步法制备了Ru/ZSM-5催化剂,利用X射线衍射、N_2吸附-脱附、NH_3-程序升温脱附和CO_2-程序升温脱附、扫描电镜和透射电镜等方法对催化剂进行了表征.考察了反应温度、钌负载量和催化剂重复利用等因素对Ru/ZSM-5上葡萄糖加氢反应性能的影响,并与浸渍法制备的Ru/ZSM-5催化剂进行了对比.结果表明,与传统浸渍法相比,一步法制备的Ru/ZSM-5催化剂钌粒子具有更高的分散性和稳定性.在120℃和4 MPa的温和反应条件下,葡萄糖接近完全转化,山梨醇选择性高达99.2%,催化剂可重复利用5次,仍保持较高活性.
Ru particles were introduced into the zeolite ZSM-5 （MFI） by either a conventional impregnation method or a one-step template-free process. The resultant materials were characterized by X-ray diffraction, N2 adsorption-desorption, scanning electron microscopy, transmission electron micros-copy, NH3 and CO2 temperature-programmed desorption. The results indicated that the Ru species in ZSM-5 catalysts prepared via the latter approach （designated as Ru/ZSM-5-TF） were highly dis-persed in the ZSM-5 framework structure and this material exhibited high catalytic performance during the hydrogenation of D-glucose to D-sorbitol. The conversion of D-glucose was as high as 99.6%with D-sorbitol selectivity reaching 99.2%, exceeding the performance of Ru/ZSM-5 catalysts prepared by the conventional impregnation method with microporous or desilicated ZSM-5 sup-ports. More importantly, this catalyst showed high stability against leaching and poisoning and could be reused several times. The extensive dispersion of the Ru species, strong interaction be-tween the Ru species and the ZSM-5, and the suitable surface acidity-basicity balance of the Ru/ZSM-5-TF were all critical factors leading to excellent catalytic behavior and stability.
出处
《催化学报》
SCIE
EI
CAS
CSCD
北大核心
2014年第5期733-740,共8页
基金
supported by the National Natural Science Foundation of China(21273260,21303238,and 21201174)
the Shandong Provincial Natural Science Foundation for Distinguished Young Scholar,China(JQ201305)
the Foundation of State Key Laboratory of Coal Conversion (J13-14-603)~~
