| Use | It is used in the CO conversion process in the ammonia synthesis and hydrogen production industry. Its catalytic reaction is CO + H2O + CO2 + H2 + Q. Through this reaction, most of the CO can be converted to produce H2, and the CO in the gas is reduced to about 3%. The reaction temperature is generally 300~530 ℃, which is commonly called high-variable catalyst in large-scale ammonia plants in foreign countries and China, and the operating temperature is usually not more than 460 ℃, while the domestic medium and small-scale ammonia plants are traditionally called medium-variable catalyst, and the operating temperature is about 500 ℃. B113 is suitable for the process conditions of the second stage of the transformation of ammonia plant in various processes of large, medium and small. B115 is an environment-friendly catalyst, suitable for various small and medium-sized ammonia plants. DG is suitable for large, medium and small ammonia plants. |
The mixing method first dissolves solid ferrous sulfate in desalinated water (deionized water), and adds ammonium carbonate solution to neutralize under stirring to generate amorphous iron hydroxide, iron carbonate and basic iron carbonate precipitate. After hot boiling and aging, rinse, filter, and dry to obtain semi-finished iron oxide. This semi-finished product is mixed and crushed with chromic anhydride (CrO3), KOH, K2CO3, other additives, adhesives (such as bentonite), lubricants (graphite), etc., and then granulated, dried, pressed and formed, calcined to obtain the finished product.
The coprecipitation method dissolves ferrous sulfate and chromic anhydride together in desalinated water, adds other additives, and adds ammonia water under stirring to precipitate iron hydroxide and chromium hydroxide together. After hot cooking, washing, filtering, drying and roasting, then crushing, adding HOH, graphite and appropriate amount of water, mixing evenly, pressing and forming, and then drying to obtain the finished product.
The mixed precipitation method first uses ammonium carbonate to neutralize ferrous sulfate solution to generate iron compound precipitation, rinse and make slurry, add chromic anhydride solution, keep at about 90 ℃, use the reduction of Fe2 to reduce soluble CrO3 to Cr2O3 and precipitate. Then KOH, graphite and other additives are added, mixed evenly, dried, granulated, molded and roasted to obtain the finished product.
The impregnation method first uses any of the above three methods to prepare the iron-chromium catalyst, and then uses the impregnation method to add other components. Such as impregnating ammonium molybdate solution, or rare earth compound solution, etc., after impregnating, drying and roasting to obtain the finished product. Ferrous sulfate is commercially available, and ferrous sulfate solution can also be prepared by dissolving metallic iron with sulfuric acid.