渣油加氢催化剂孔径对沥青质扩散行为的影响  

Impact of pore size of residue hydrotreating catalyst on asphaltene diffusion behavior

作　　者：孙昱东[1] 杨晓明 韩忠祥[1] 陈洁 Sun Yudong;Yang Xiaoming;Han Zhongxiang;Chen Jie(School of Chemical Engineering,China University of Petroleum（East China）,Qingdao,Shandong 266580;Zhejiang Energy Natural Gas Group Co.,Ltd.,Hangzhou,Zhejiang 310052)

机构地区：[1]中国石油大学(华东)化学工程学院,山东省青岛市266580 [2]浙江能源天然气集团有限公司,浙江省杭州市310052

出　　处：《炼油技术与工程》2018年第10期41-44,54,共5页Petroleum Refinery Engineering

基　　金：国家自然科学基金项目(21376266)

摘　　要：以塔河常压渣油的正庚烷沥青质为原料,采用5种工业Al_2O_3基渣油加氢处理催化剂研究了沥青质在不同孔径的渣油加氢催化剂中的扩散行为。上述催化剂(分别标注为A,B,C,D,E)的内部特征不同,外部均为横截面直径约0. 9 mm的四叶草形,轴向长度约10 mm。结果表明,孔径对沥青质聚集体的扩散过程具有重要影响。大孔径条件下,沥青质在催化剂中的扩散近似于自由扩散;随催化剂孔径减小,沥青质的扩散系数逐渐减小,由自由扩散过渡为受阻扩散;当催化剂孔径与沥青质聚集体尺寸相近时,沥青质在催化剂中的扩散变得非常困难。有效扩散系数随催化剂孔径的变化非常明显,渣油加氢过程必须选择合适孔径的催化剂,以避免因受阻扩散带来的过度结焦和失活问题。The diffusion behaviors of 5 kinds of Al2O3 based hydrotreating catalysts in different asphaltenes are studied. The internal characteristics of the these catalysts are different. The external shape is the shape of four-pedal grass with a diameter of 0.9 mm. The shaft is as long as 10 mm. The catalysts are marked A, B, C, D and E. The results show that the catalyst pore size has a great impact on the diffusion be- havior of asphahene aggregates. The diffusion of asphahene in the catalyst is almost free diffusion under the condition of large pore size. The diffusion coefficient of asphahene goes down gradually with the catalyst pore size becoming smaller and the diffusion changes from free diffusion to hindered diffusion~ The diffusion of as- phaltene in catalyst becomes very difficult when the pore size of catalyst is close to that of asphaltene aggre- gates. The effective diffusion Coefficient changes obviously with the pore size of catalyst. The catalyst with ap- propriate pore size must be selected for residue hydrotreating to avoid excessive coking and deactivation caused by hindered diffusion.

关 键 词：渣油加氢 催化剂孔径 沥青质 有效扩散系数 

分 类 号：TE624.9[石油与天然气工程—油气加工工程]