负载型TiO_2-Al_2O_3复合载体在超深度加氢脱硫中的应用  

Application of TiO_2-Al_2O_3 composite support on ultra deep hydrodesulfurization

作　　者：李生祥[1] 李伟[1] 张明慧[1] 陶克毅[1] 

机构地区：[1]南开大学化学学院材料化学系新催化材料科学研究所,天津300071

出　　处：《燃料化学学报》2005年第6期742-745,共4页Journal of Fuel Chemistry and Technology

基　　金：国家自然科学基金(20273035;20233030);天津市自然科学基金(033802511);南开大学创新课题基金~~

摘　　要：运用HRTEM、FT-Ram an、TPR等方法表征了M o活性组分在负载型T iO2-A l2O3复合载体和A l2O3上不同形态和性质。比较了T iO2-A l2O3复合载体同传统A l2O3载体对CoM o催化剂结构的影响,并以4,6-二甲基二苯并噻吩(4,6-DMDBT)为探针考察了催化剂的超深度加氢脱硫(UHDS)性能。结果表明,在负载型T iO2-A l2O3复合载体中,M oO3同载体之间的相互作用较弱,这种弱的相互作用使M oO3更多的以八面体配位M o物种(M oⅥ)及其二维的聚合物的形式存在。二维聚合物有利于形成具有更高活性的多层M oS2结构,明显提高催化剂的超深度加氢脱硫催化活性。We have studied a series of CoMo hydrodesulfurization （HDS） catalysts supported on TiO2-Al2O3 composite oxide and Al2O3. The difference of these catalysts was investigated by TPR（ Temperature Programmed Reduction）, FT-Raman, and HRTEM （High Resolution Transmission Electron Microscopy） techniques. The HDS tests were performed in a high pressure fixed bed micro-reactor with 4,6-DMDBT （4,6-Dimethyldibenzothiophene） as a probe molecule. TPR spectra results indicated that the interaction between MoO3 and TiO2-Al2O3 composite support was weaker than MoO3 and Al2O3 support, which resulted in more octahedral Mo species （ Mo^Ⅵ ） forming on the surface of support. Raman spectra showed that the existence of TiO2 in TiO2-Al2O3 composite support made the highest band of MoOx species shift from 958 cm^-1 in MoO3/Al2O3 to 965 cm^-1 in MOO3/ TiO2-Al2O3. The blue-shift of this band which was attributed to terminal Mo == O of Mo7O24^6- implicated that the degree of aggregation of polymeric molybdenum-oxide units had increased. HRTEM graphs showed there were more multilayer MoS2 clusters in catalyst supported on TiO2-Al2O3 composite support. And multilayer MoS2 clusters were considered to be more active in HDS. The HDS tests of 4,6-DMDBT showed that the catalyst supported on TiO2-Al2O3 had higher activity than on Al2O3.

关 键 词：TiO2-Al2O3 TPR 复合载体 HDS 加氢 

分 类 号：TE624.43[石油与天然气工程—油气加工工程]