摘要
采用类凝胶法和超临界流体干燥技术制备了超细Mo -Co -K催化剂。通过BET、TEM、XRD和TPR等表征手段比较分析了不同制备参数尤其是Co/Mo比对超细Mo-Co -K催化剂性能的影响。结果表明 ,制得的催化剂为大比表面积、小粒径、大孔超细粒子。超细催化剂中Mo、Co、K之间具有较强的相互作用 ,形成了CoMoO4 和K2 Mo4 O13 物种。超细Mo基催化剂中加入Co和K均可降低催化剂的还原温度。合成低碳醇反应评价结果表明 ,超细Mo -Co-K催化剂具有很高的催化活性、选择性以及生成碳二以上醇的选择性。
Ultrafine Mo-Co-K catalysts were prepared by the “gel-like”method followed by supercritical fluid drying technique The texture and structure of ultrafine Mo-Co-K catalysts were characterized by BET, TEM, XRD and TPR, and the performances for alcohol synthesis on reduced catalysts from syngas were investigated It was revealed that appropriate addition of cobalt and potassium into the catalyst system resulted in an increase of the specific surface area and a decrease of the average pore radius of the catalyst, but more addition of cobalt and potassium showed a quite opposite trend At Co/Mo=1∶7 and K w%=1%, the catalyst got its maximum specific surface area and minimum average pore radius of 22 13 m 2/g and 8 93 nm, respectively Mo, Co and K in ultrafine Mo-Co-K catalysts showed strong interaction which led to the formation of CoMoO 4 and K 2Mo 4O 13 The incorporation of cobalt and potassium into the catalyst system resulted in the decrease of the reduction temperature of the catalyst, which could be attributed to the interaction among Mo, Co and K The incorporation of cobalt into the catalyst system not only improved the selectivity for alcohols and activity of the catalyst significantly, but also shifted the distribution of alcohols towards higher ones The incorporation of potassium into the catalyst system obviously increased both activity and selectivity for the formation of alcohols and shifted the product distribution of alcohols towards lower ones Optimum activity to alcohols could be achieved at an optimum Co/Mo atomic ratio (1∶7) and K content (w 1%), i.e., Alc STY=624 4g/kg h, Alc sel =48 5% and C 2+ OH/C 1OH=1 08 under 300℃, 6 0MPa, and 10000h -1
出处
《燃料化学学报》
EI
CAS
CSCD
北大核心
2000年第3期244-248,共5页
Journal of Fuel Chemistry and Technology
基金
国家自然科学基金! (2 95 0 30 2 6 )
