Patent ID: 6248687
Filing Date: 2001-06-19
Classification: B01J,C10G

Abstract:
Process comprising presulfurizing a desulfurization catalyst to be used in a hydrodesulfurization unit of petroleum refinery of high molecular weight hydrocarbons, in which fresh metal oxide in said desulfurization catalyst is sulfurized with hydrogen sulfide produced from sulfur-containing compounds in a feed stream, said presulfurization is effected between about 180.degree. C. to about 260.degree. C. by adding at least one compound having at least one mercapto alkylthio group, which is added 10 ppm to 0.5% by weight with respect to the total amount of said feed stream, said compound having at least one mercapto alkylthio group represented by the formula:(R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, R.sub.6)--(S--C.sub.m H.sub.2m --SH).sub.nin which each of R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, and R.sub.6 is an organic group and is bonded to each other through at least one chemical bond, and at least R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, and R.sub.6 must exist in the compound, the total carbon number of R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, and R.sub.6 being 2 to 28, ""m"" is an integer of 2 to 4, and ""n"" is an integer of 1 to 6.