A kind of iron-based catalyst and its preparation method and application

Abstract

The invention discloses a method for preparing an iron-based catalyst, which comprises the following steps: (1) The alumina carrier is saturated and impregnated with a nitrogen-containing organic compound aqueous solution, and dried until the adsorption amount of the nitrogen-containing organic compound aqueous solution is the amount of the saturated absorption solution of the alumina carrier 30-60% of the modified alumina carrier obtained after roasting; (2) Prepare a mixed aqueous solution of nickel salt and gallium salt, and the modified alumina carrier prepared in step (1) is impregnated with the above mixed aqueous solution by an unsaturated impregnation method, Drying and roasting; (3) Impregnating the carrier after step (2) roasting with the wetting solution containing the adsorbent by unsaturated impregnation method; (4) The carrier containing the adsorbent in step (3) is dried and then saturated and co-impregnated with active The mixed solution of metal iron, additive manganese and additive potassium is dried and calcined to prepare a catalyst for producing low-carbon olefins from syngas. The catalyst has the characteristics of high activity and stability in long-period operation, and is beneficial to industrial application and popularization.

Description

technical field [0001] The invention relates to an iron-based catalyst and its preparation method and application, in particular to a highly active and stable supported iron-based syngas-based low-carbon olefin catalyst and its preparation method. Background technique [0002] Low-carbon olefins such as ethylene and propylene are important basic organic chemical raw materials. With the development of the chemical industry, their demand is increasing. So far, the way to produce low-carbon olefins such as ethylene and propylene is mainly through the cracking process of light oil. With the increasing depletion of oil resources worldwide, the future energy structure will inevitably shift. Compared with oil resources, coal and natural gas resources are relatively abundant, and it is of great significance to develop low-carbon olefin production processes based on coal and natural gas. The development of direct production of ethylene and propylene technology from syngas (which can...

AI Technical Summary

Problems solved by technology

[0003] CN1065026A discloses a method for producing ethylene from synthesis gas, which involves the preparation of catalysts by chemical precipitation and mechanical mixing, using precious metals or rare metals, such as niobium, gallium, praseodymium, scandium, indium, cerium, lanthanum, ytterbium, etc. For other chemical elements, the selectivity of ethylene is 65%-94%, but the conversion rate of CO is very low, only about 10%, 12% and 15%. The recycling of CO will inevitably lead to energy consumption, and the catalyst cost is high

However, the activity stability of the long-term operation of the above-mentioned Fe-based silica gel-supported synthesis gas to directly prepare low-carbon olefins catalysts still needs to be further improved.