载体效应对Pb基催化剂丙烷脱氢性能的影响  

Effect of Carriers on Propane Dehydrogenation Over Pb-based Catalyst

作　　者：张焕玲 马会霞 周峰 赵成浩 杨明源 王梦琦 王国玮[2] 祝晓琳[2] 李春义[2] ZHANG Huanling;MA Huixia;ZHOU Feng;ZHAO Chenghao;YANG Mingyuan;WANG Mengqi;WANG Guowei;ZHU Xiaolin;LI Chunyi(SINOPEC(Dalian)Research Institute of Petroleum and Petrochemical Co.,Ltd.,Dalian 116000,China;State Key Laboratory of Heavy Oil Processing,China University of Petroleum(East China),Qingdao 266580,China)

机构地区：[1]中石化(大连)石油化工研究院有限公司,辽宁大连116000 [2]中国石油大学(华东)重质油全国重点实验室,山东青岛266580

出　　处：《石油学报(石油加工)》2025年第2期498-506,共9页Acta Petrolei Sinica(Petroleum Processing Section)

基　　金：国家自然科学基金项目(22178390);山东省自然科学基金项目(ZR2022MB023)资助。

摘　　要：鉴于载体性质会影响Pb基催化剂的脱氢性能,以本身无脱氢活性的SiO_(2)负载的Pb基催化剂作对比催化剂,通过XRD、N_(2)吸附-脱附、NH_(3)-TPD、H 2-TPR、Raman、27 Al NMR等表征方法,研究了Al_(2)O_(3)、MgAl_(2)O_(4)自身脱氢活性对Pb基催化剂丙烷脱氢性能的影响并探究了其作用原理。实验结果表明,在温度600℃、MHSV为0.22 h^(-1)的反应条件下,15Pb/Al_(2)O_(3)和15Pb/MgAl_(2)O_(4)催化剂在反应初始表现出最佳丙烷转化率,分别为38.7%和41.1%;随着反应进行脱氢活性下降,但分别在0.5和2.0 h后脱氢活性出现上升趋势,且丙烷转化率在3.0和4.5 h再次达到极点,分别为33.1%和32.0%,对应的丙烯选择性分别为62.3%和70.4%。研究表明,Al_(2)O_(3)、MgAl_(2)O_(4)负载的Pb基催化剂中存在2种脱氢活性物种,一种是Pb物种,另一种是反应过程中生成的配位不饱和Al^(3+)物种,且载体自身脱氢活性利于催化剂脱氢活性的提升。此外,采用脱氢原理与Al_(2)O_(3)类似的ZrO_(2)对载体效应进行了验证,并证明了载体与Pb物种协同脱氢的普适性。但Al_(2)O_(3)、MgAl_(2)O_(4)、ZrO_(2)中酸性物种含量高、易诱发副反应,不利于丙烯选择性的提高。Considering that carrier properties may affect the dehydrogenation performance of Pb-based catalyst,the Pb/SiO_(2)catalyst was used as the reference sample because pure SiO_(2)exhibits no dehydrogenation activity.Uing the characterization methods such as XRD,N_(2)adsorption-desorption,NH_(3)-TPD,H 2-TPR,Raman,and 27 Al NMR,the effect of the dehydrogenation ability of Al_(2)O_(3)and MgAl_(2)O_(4)on propane dehydrogenation over the Pb-based catalyst was studied,and the action mechanism was also explored.The results show that both 15Pb/Al_(2)O_(3)and 15Pb/MgAl_(2)O_(4)catalysts exhibit the highest propane conversion at the initial stage of reaction at the temperature of 600℃and MHSV of 0.22 h^(-1),which are 38.7%and 41.1%,respectively.The dehydrogenation activity declines with time on stream,showing a rising trend after 0.5 and 2.0 h,respectively,and the propane conversion reaches the maximum again at 3.0 and 4.5 h,i.e.,33.1%and 32.0%,and the corresponding propane selectivity is 62.3%and 70.4%,respectively.Research shows that the Pb-based catalyst supported by Al_(2)O_(3)and MgAl_(2)O_(4)has two active dehydrogenation species,one is Pb species,and the other is the coordinatively saturated Al^(3+)species generated during the reaction.Moreover,the dehydrogenation activity of carrier itself can enhance the dehydrogenation activity of Pb-based catalyst.In addition,the carrier effect has been verified by the dehydrogenation principle and ZrO_(2)catalyst similar to that of Al_(2)O_(3),and the general applicablity of a combination of carrier and Pb species for dehydrogenation is also proved.However,the high content of acid species in Al_(2)O_(3),MgAl_(2)O_(4)and ZrO_(2)are easy to induce side reactions,which is detrimental to the improvement of propene selectivity.

关 键 词：载体效应 Pb基催化剂 丙烷脱氢 丙烯 Al_(2)O_(3) MgAl_(2)O_(4) 

分 类 号：O643.38[理学—物理化学]