文摘
Two-stage processes are possible solutions for reaching 10 ppm sulfur in gas oil without severe runningconditions. First, most of the sulfur is removed by using a CoMo conventional catalyst. Second, after H2Sremoval, the treated oil, with a remaining S content below 500 ppm, is again hydrotreated. In this latter case,the use of noble metal catalysts can be envisaged. In the present study dealing with this second stage reactor,we examined a catalytic system based on the addition of a low content of Pt to a commercial sulfide catalyst.An enhancement in catalytic activity can be obtained in the conversion of model molecules (tetralin anddibenzothiophene) as well as a hydrotreated straight run gas oil. The promotion effect strongly depends onthe preparation procedure which requires the impregnation of Pt on a presulfided commercial HDT catalyst.Advanced EXAFS and HRTEM characterizations were used to characterize the active phases.
