选择性加氢脱硫催化剂Co-Mo/TiO_2-Al_2O_3的制备与表征

采用溶胶-凝胶法获得TiO2-Al2O3复合载体,研究了该复合载体负载Co、Mo后制备的Co-Mo/TiO2-Al2O3催化剂在FCC汽油重馏分加氢脱硫反应中的催化性能,重点考察了复合载体TiO2/(TiO2+Al2O3)对催化剂加氢脱硫活性和选择性的影响,并对催化剂和载体进行了BET、IR和NH3-TPD表征.实验结果表明:催化剂加氢脱硫活性和选择性均随载体中TiO2含量的增加而增加.表征结果表明催化剂的比表面积、孔容和平均孔径均随载体中Ti O2含量的增加而减小;随着TiO2含量的增加,催化剂酸中心强度和酸量有所增大,但变化量不大;催化剂载体的L酸量逐渐增大.载体表面仅有微量的B酸.

Preparation and characterization of Co-Mo/TiO2-Al2O3 catalysts for selective hydrodesulphurization

Composite oxide supports of TiO_2-Al_2O_3 are prepared using a sol-gel method.Co-Mo/TiO_2-Al_2O_3 catalysts are obtained by the impregnation of ammonium molybdate and cobalt nitrate.The catalytic performance of the catalysts for the hydrodesulphurization of FCC gasoline heavy distillates is studied.The influences of the ratio of TiO2 to (TiO2+Al2O3) on the desulphurization activity and selectivity of the catalysts are studied.The catalysts are characterized by BET,TPD and FT-IR.The results show that with the increase of the amount of TiO2 in the supports,the selectivity and activity of the catalyst increase,and the specific surface area,pore volume and averaging pore radius of the catalysts decrease.With the increase of the TiO2,the intensity and amount of acid increase a little,and the L acid amount of the supports increases.There is only a little B acid on the surface of the supports.