Patent ID: 6800585
Filing Date: 2004-10-05
Classification: B01D,B01J

Abstract:
A method for preparing a catalyst for selective catalytic reduction of nitrogen oxides from spent catalysts having been adsorbed with vanadium, nickel and sulfur in the hydro-desulfurization line of an oil refinery in which a catalyst for the hydro-desulfurization contains molybdenum, iron, cobalt and silicon on the alumina support, comprising the following steps of:providing a first material comprising 10 wt % or more of vanadium, 5 wt % or more of nickel, 5 wt % or more of sulfur and 3 wt % or less of molybdenum, and having a specific surface area of 60 m2/g or smaller and pore sizes of 250 Ã¥ or larger from said spent catalysts; providing a second material comprising 3 wt % or less of vanadium, 4 wt % or less of nickel, 2 wt % or less of sulfur and 5 wt % or more of molybdenum, and having a specific surface area of 130 m2/g or larger and pore sizes of 150 Ã¥ or smaller from said spent catalysts; pretreating the first and second materials, separately, at 300 to 400Â° C.; pulverizing each of the preheated materials to an average particle size of 100 to 200 mesh; mixing the first material with acid and water, then with the second material; and drying the mixture at 100 to 120Â° C. and then calcining at 450 to 550Â° C.