COBALT/ZIRCONIUM-PHOSPHORUS/SILICA CATALYST FOR FISCHER-TROPSCH SYNTHESIS AND METHOD OF PREPARING THE SAME
The present invention relates to a cobalt/zirconium-phosphorus/silica catalyst in which cobalt, as an active ingredient, is impregnated on a zirconium-phosphorus/silica support prepared by treating the surface of silica with zirconium and phosphorus, and a method of preparing the catalyst. The catalyst has excellent reactivity since it has excellent heat and mass transfer properties due to a large pore structure of silica and increased reducibility of cobalt; excellent dispersion of cobalt and other activation substances during Fischer-Tropsch (F-T) reaction; and reduced sintering of cobalt particles during the reaction, and thus high CO conversion and stable selectivity for liquid hydrocarbon can be obtained during the F-T reaction.
1 . A cobalt/zirconium-phosphorus/silica catalyst for Fischer-Tropsch reaction in which cobalt, as an active ingredient, is impregnated on a support,
wherein the support is a zirconium-phosphorus/silica support in which zirconium (Zr) and phosphorus (P) are simultaneously contained on the surface of porous silica having a specific surface area of 200 to 800 m 2 /g,
wherein the amount of zirconium-phosphorus is in the range of 2 to 30 wt% relative to the silica, the amount of zirconium is in the range of 5 to 100 wt% relative to phosphorus, and the amount of cobalt (Co) is in the range of 10 to 40 wt% relative to the zirconium-phosphorus/silica support.
2 . The cobalt/zirconium-phosphorus/silica catalyst of claim 1 , further comprising 0.05 to 2 wt% of a catalyst promoter selected from the group consisting of Ru, Pt, and Rh, relative to the cobalt/zirconium-phosphorus/silica catalyst.
3 . The cobalt/zirconium-phosphorus/silica catalyst of claim 1 , having a specific surface area of 190 to 300 m 2 /g.
4 . A method of preparing a cobalt/zirconium-phosphorus/silica catalyst for Fischer-Tropsch reaction, the method comprising:
preparing a zirconium (Zr)-phosphorus (P)/silica support by simultaneously containing a zirconium precursor and a phosphorus precursor on porous silica having a specific surface area of 200 to 800 m 2 /g, drying at a temperature of 100 to 200° C., and calcining at a temperature of 300 to 800° C.; and
preparing a cobalt/zirconium-phosphorus/silica catalyst by supporting a cobalt precursor on the zirconium-phosphorus/silica support, drying at a temperature of 100 to 200° C., and calcining at a temperature of 100 to 700° C.
5 . The method of claim 4 , wherein the supporting process is performed by impregnation or co-precipitation method.
6 . The method of claim 5 , wherein the co-precipitation is performed using a basic precipitant, selected from the group consisting of sodium carbonate, potassium carbonate, ammonium carbonate, and ammonia water, so as to maintain the pH in the range of 7 to 8.
7 . The method of claim 4 , wherein the zirconium precursor is a single compound selected from the group consisting of zirconium oxynitrate (ZrO(NO 3 ) 2 .xH 2 O), zirconium oxychloride (ZrOCl 2 .xH 2 O), zirconium sulfate (Zr(SO 4 ) 2 ), and zirconium chloride (ZrCl 4 ), or a mixture of at least two of these compounds.
8 . The method of claim 4 , wherein the phosphorus precursor is a single compound selected from the group consisting of phosphoric acid (H 3 PO 4 ), phosphorus oxychloride (POCl 3 ), phosphorus pentaoxide (P 2 O 5 ), and phosphorus trichloride (PCl 3 ), or a mixture of at least two of these compounds.
9 . The method of claim 4 , wherein the amount of zirconium-phosphorus is in the range of 2 to 30 wt% relative to silica.
10 . The method of claim 4 , wherein the amount of zirconium is in the range of 5 to 100 wt% relative to phosphorus.
11 . The method of claim 4 , wherein the cobalt precursor is a single compound selected from the group consisting of nitrate, acetate, and chloride, or a mixture of at least two of these compounds.
12 . The method of clam 4 , wherein the amount of cobalt is in the range of 10 to 40 wt% relative to the zirconium-phosphorus/silica support.