硅铝比对镁碱沸石催化剂催化正丁烯异构化性能的影响  

Isomerization of n-Butene on Ferrierite Catalysts with Different Silica-Alumina Ratio

作　　者：周广林[1] 王晓胜[1] 陈志伟 周红军[1] 

机构地区：[1]中国石油大学(北京)新能源研究院,北京102249

出　　处：《石油化工》2015年第2期186-191,共6页Petrochemical Technology

摘　　要：采用水热合成法,通过改变投料配比,在硅铝比分别为20,40,60,80,100,120时合成了镁碱沸石,经挤条成型后制得催化剂。采用XRD、低温N2吸附-脱附、SEM、NH3-TPD和吡啶吸附FTIR等方法对合成的镁碱沸石进行了表征,并在固定床反应器上以正丁烯骨架异构化制异丁烯为探针反应评价了催化剂的性能。表征结果显示,硅铝比对镁碱沸石的比表面积和孔体积的影响较小,对相对结晶度、晶粒粒径和酸性等影响较大,硅铝比为60~80时合成的镁碱沸石具有最高的相对结晶度、较大的晶粒尺寸、适宜的酸量及L/B酸的比值。反应结果表明,硅铝比为60~80时合成的镁碱沸石催化剂的正丁烯骨架异构化活性和稳定性最好,异丁烯收率较高且副产物丙烯收率较低。Ferrierites with different silica-alumina ratio in feed（20,40,60,80,100 and 120） were synthesized by hydrothermal method and characterized by means of XRD,N2 adsorption-desorption,SEM,NH3-TPD and Py-FTIR. The results showed that the crystallinity,grain size,acidic amount and L acid/B acid ratio were signifi cantly affected by the silica-alumina ratio whereas the effects of the silica-alumina ratio on the specifi c surface area and pore volume were little. The ferrierites synthesized with 60-80 of the silica-alumina ratio had the maximum relative crystallinity,large crystal size,suitable acidic amount and L acid/B acid ratio. The skeletal isomerization of n-butene to i-butene was conducted on the ferrierite catalysts in a fi xed-bed reactor. The results showed that the optimal silicaalumina ratio for the n-butene isomerization should be in the range of 60-80. Under this condition the activity and stability of the catalysts were the best,with the high i-butene yield and the low by-product propene yield.

关 键 词：硅铝比 镁碱沸石催化剂 正丁烯异构化 异丁烯 

分 类 号：TQ426[化学工程]