Method for producing chromium metal by using carbon reduction two-step method

Abstract

The invention discloses a method for producing chromium metal by using a carbon reduction two-step method, which comprises the following steps: grinding 100 parts of chromium sesquioxide with the purity of 94 to 99.5 percent and 25 to 44 parts of carbon powder, mixing and stirring the ground powder uniformly, pressing the powder to form balls, and putting the balls into a high temperature furnace to perform primary carbon reduction treatment to generate chromium carbon melt; crushing the melt into fine powder of 80 to 200 meshes, measuring the carbon content, adding the chromium sesquioxide into the melt in a ratio of oxygen to carbon of 1: 33, stirring the mixture fully and uniformly, and pressing and drying the mixture; and putting the dried blank into a vacuum high-humidity furnace, keeping the blank wet for 14 to 15 hours under the vacuum of 20 to 200Pa at the furnace temperature of between 1,300 and 1,600 DEG C, or putting the blank into the high temperature furnace filled with argon, heating the blank to 2,000 DEG C to be smelted, preserving the heat for 2 hours, casting the blank to form blocks, and discharging the blocks after cooling. The method can produce chromium metal products of multiple specifications with the purity of 94 to 99.5 percent, and has large production capacity and high work efficiency so as to achieve the purpose of industrialized production.

Description

technical field [0001] The invention relates to a production method for extracting metal chromium by carbon reduction reaction, and the international classification number is C22B34 / 32. Background technique [0002] Metal chromium is a basic raw material, widely used in metallurgy, chemical industry, aerospace and refractory fields. The current production methods of metal chromium include thermite method, electrolysis method and carbon reduction method. [0003] The thermite method not only consumes a large amount of valuable aluminum powder, but also the recovery rate of the product is not high, usually not more than 88%. The product also contains a large amount of impurities such as Fe, Si, Al, etc., and the purity is not good. [0004] The advantage of the electrolysis method is that the product has high purity and the chromium content is greater than 99.5%. The disadvantages are large power consumption, serious pollution and high production cost in the production proc...

AI Technical Summary

Problems solved by technology

The disadvantage is that the quality requirements of raw materials are relatively high, and only chromium oxide with a purity of more than 99% can be processed, and the product specification is single

Since the vacuum furnace is used in the whole production process, the production capacity is small, the work efficiency is low, and it is not suitable for industrial production.