Abstract: Disclosed are a catalyst for selective catalytic reduction of nitrogen oxides and a method for preparing the same. Useful for the removal of nitrogen oxides is a catalyst prepared using spent catalysts having been absorbed 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 in accordance with the present invention. The present catalyst can remove nitrogen oxides at a level of 90% or higher, exhibiting a 10% or more increase in efficiency of the catalyst performance. Additionally, the catalyst can increase the efficiency of spent catalyst reclamation by 250%.

Abstract: Disclosed are a catalyst for selective catalytic reduction of nitrogen oxides and a method for preparing the same. Useful for the removal of nitrogen oxides is a catalyst prepared using spent catalysts having been absorbed 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 in accordance with the present invention. The present catalyst can remove nitrogen oxides at a level of 90% or higher, exhibiting a 10% or more increase in efficiency of the catalyst performance. Additionally, the catalyst can increase the efficiency of spent catalyst reclamation by 250%.

Abstract: The catalyst is prepared by recycling a spent catalyst discharged from a hydro-desulfurization process of an oil refinery in which the spent catalyst comprises an alumina support with a large specific surface area impregnated with low contents of vanadium and high contents of molybdenum. The thus prepared catalyst has more excellent selective removal activity of nitrogen oxides at a high temperature window by containing suitable amounts of metal components therein as well as a better poisoning resistance to sulfur oxides, compared with the conventional catalysts.

Abstract: Disclosed are a catalyst for removing dioxin and a preparation method thereof. The catalyst is prepared by recycling a spent catalyst discharged from a hydro-desulfurization process of an oil refinery in which the spent catalyst comprises an alumina support (preferably, gamma alumina) with a large specific surface area impregnated with high contents of vanadium. The spent catalyst is mixed with a tungsten-impregnated titania, whereby a catalyst comprising suitable metal components and a mixture support of alumina and titania may be prepared. The catalyst in accordance with the present invention has excellent dioxin removal performance and low preparation cost because of recycling the spent catalyst.

Abstract: Disclosed is a method for preparing a catalyst for selective catalytic reduction of nitrogen oxides at high temperature window. The catalyst is prepared by recycling a spent catalyst discharged from a hydro-desulfurization process of an oil refinery in which the spent catalyst comprises an alumina support with a large specific surface area impregnated with low contents of vanadium and high contents of molybdenum. The thus prepared catalyst has more excellent selective removal activity of nitrogen oxides at a high temperature window by containing suitable amounts of metal components therein as well as a better poisoning resistance to sulfur oxides, compared with the conventional catalysts.