Desulfurizer for conversion and absorption of high-concentration carbonyl sulfide and a desulfurizer for catalytic conversion and absorption of carbon disulfide and their preparation methods
Provided is a high-concentration carbonyl sulfide conversion-absorption type desulfurizer for use at medium-low temperature and preparation method thereof. The desulfurizer comprises 50%-75% magnetic iron oxide red (Fe 21.333 O 32 ), 5%-10% alkali metal oxide (K 2 O), 5-35% anatase TiO 2 , and 5-10% shaping binder. The method of preparing the desulfurizer comprises: uniformly mixing a metatitanic acid prepared using ferrous sulfate recycled as a by-product from titanium dioxide production with K 2 CO 3 , calcining to activate at 500° C.-700° C., mixing with the magnetic iron oxide red and binder, roll molding at room temperature to form balls which are dried at 100° C.-150° C. to obtain the desulfurizer. The desulfurizer has a hydrolysis conversion of carbonyl sulfide higher than 99%, and has a higher sulfur capacity more than 25%.
1. A method for preparing a desulfurizer, the method comprising:
(1) mixing and reacting a FeSO 4 solution with an alkaline substance solution or solid by controlling the alkali ratio of the alkaline substance solution or solid and the FeSO 4 solution to 1-1.1 to form a first mixture, filtering the first mixture to yield a filter cake, and calcining the filter cake at a temperature of 250-400° C. to yield the magnetic iron oxide red Fe 21.333 O 32 ; or
mixing and kneading a FeSO 4 solid with an alkaline substance solid by controlling the alkali ratio of the alkaline substance solid and the FeSO 4 solid to 1-1.1 to form a first mixture, followed by washing with water and filtering the first mixture to yield a filter cake, and calcining the filter cake at a temperature of 250-400° C. to yield the magnetic iron oxide red Fe 21.333 O 32 ; and
(2) mixing 50-75 parts by weight of the magnetic iron oxide red Fe 21.333 O 32 with 5-35 parts by weight of anatase type TiO 2 , 5-10 parts by weight of K 2 O and 5-10 parts by weight of a binder to form a second mixture, followed by roll molding at room temperature and drying the second mixture to produce the desulfurizer;
wherein the anatase type TiO 2 and K 2 O in Step (2) are prepared by mixing and calcining 6.1-42.7 parts by weight of metatitanic acid and 7.3-14.7 parts by weight of K 2 CO 3 at a temperature of 500-700° C.
2. The method of claim 1 , wherein the filter cake in the step (1) is calcined at 350° C. for 2-5 hours.
3. The method of claim 1 , wherein the alkaline substance is selected from the group consisting of hydroxides of Group IA, Na 2 CO 3 , (NH 4 ) 2 CO 3 , K 2 CO 3 , NaHCO 3 , NH 4 HCO 3 , KHCO 3 and any combination thereof.
4. The method of claim 1 , wherein the metatitanic acid is prepared by a method comprising
preparing a ferrous sulfate solution by dissolving a ferrous sulfate solid in water, wherein the ferrous sulfate solid is a by-product from titanium dioxide production by a sulfuric acid method,
heating the ferrous sulfate solution up to 40-100° C.,
adjusting a pH value of the ferrous sulfate solution to 1-2 by adding an acid, and
reacting the ferrous sulfate solution with a flocculating agent to yield a precipitate, followed by filtering the precipitate to obtain the metatitanic acid.
5. The method of claim 4 , wherein the ferrous sulfate solution has a FeSO 4 concentration of 1-2.5 mol/L.
6. The method of claim 4 , wherein the acid added for adjusting the pH value is selected from the group consisting of nitric acid, hydrochloric acid, sulfuric acid and any combination thereof.