Method for extracting and separating nickel and molybdenum from nickel-molybdenum-containing coal gangue

Abstract

The invention discloses a method for extracting and separating nickel and molybdenum from nickel-molybdenum-containing coal gangue. The method comprises the steps of: pulverizing raw ores and blending sodium carbonate to prepare pellets, and smelting the coal gangue at high temperature by using carbon contained in the coal gauge per se to extract nickel and obtaining ferro-nickel alloy and molten slag; lixiviating the ferro-nickel alloy with water to obtain molybdenum-containing lixivium; and carbonating the molybdenum-containing lixivium by using CO2-containing furnace gas generated in high-temperature smelting to precipitate sulfur and sodium hydroxide in sequence, and filtering to obtain the sulfur and the sodium hydroxide, wherein the sodium carbonate is recycled for the step of high-temperature smelting, and filtrate is further subjected to a molybdenum wet-process smelting process for molybdenum extraction. Compared with the traditional method, the method disclosed by the invention is an efficient, economic and harmless production method and has the advantages that a carbon reducing agent is unnecessary to add, the nickel and the molybdenum are effectively separated and have high purity and raw materials are utilized comprehensively and favorably.

Description

technical field [0001] The invention relates to a method for extracting and separating nickel and molybdenum from stone coal mines containing nickel and molybdenum, including some pyrotechnic and wet process units of nonferrous metallurgy, and belongs to the technical field of mineral extraction metallurgy. Background technique [0002] Both molybdenum and nickel are important non-ferrous metals. According to the classification of non-ferrous metals, nickel is a heavy non-ferrous metal, and molybdenum is a rare non-ferrous metal. Both are important strategic metals. Both molybdenum and nickel are widely used in the steel industry and are indispensable raw materials for the production of high-quality alloy steel. They are also widely used in the chemical industry, electronics industry, defense industry, aviation industry, and machine manufacturing industry. [0003] More than 98% of the metal molybdenum, molybdenum alloys and molybdenum compounds used in the world are made of...

AI Technical Summary

Problems solved by technology

The disadvantage of this method to extract molybdenum from stone coal containing molybdenum and nickel is that the yield of molybdenum is low, the cost is high, and nickel cannot be recovered at the same time, especially the sulfur-containing gas generated during roasting is very serious to the pollution of the atmospheric environment.

[0007] Invention patent CN1033784A provides a concentrated acid thermal leaching, depolymerization, and solvent extraction process of nickel-molybdenum symbiotic ore. Its main features are to crush, roast, leaching, extraction, stripping, acidification, and concentrated crystallization of minerals to obtain ammonium molybdate And nickel sulfate, it is said that the recovery rate of molybdenum is 95%, and the recovery rate of nickel is 70%, but the invention is still not free from oxidation roasting

The invention claims that the yield of molybdenum is 90%, and the yield of nickel is 93%. Although the invention has got rid of the roasting process and eliminated the pollution to the quality of the air environment, the comprehensive utilization is better, and the recovery rate of molybdenum and nickel is also higher. However, a large amount of sulfuric acid and chemical raw materials are required, more equipment is required and anti-corrosion is required, and the process is longer and the processing capacity is small.

[0009] 5M is used in the area from Jishou to Zhangjiajie in Hunan, my country 3 Coarse nickel-molybdenum alloys are smelted in small blast furnaces or 630 kVA electric furnaces. The process is to crush nickel-molybdenum ores, desulfurize them by heaping them, add lime and coke to the roasted materials, and directly reduce them in small blast furnaces or electric furnaces to produce crude nickel-molybdenum alloys. Nickel-molybdenum alloy, the obtained nickel-molybdenum alloy contains 15-20% molybdenum, 8-10% nickel, phosphorus > 0.6%, sulfur > 1%, this method is a pure fire production process, and this method is used to process molybdenum and nickel. Although the stone coal has the advantages of simple equipment and process, large amount of raw material processing, low production cost, and high yield of molybdenum and nickel, its disadvantage is that the smelting product is a molybdenum-nickel alloy eutectic, and molybdenum and nickel Failure to separate, and the harmful impurities phosphorus and sulfur content in the alloy are high, and the use is limited. Subsequent molybdenum and nickel separation and impurity removal treatment must be carried out to obtain qualified molybdenum and nickel products, which eventually leads to a decrease in the yield of molybdenum and nickel. Increased cost, especially the SO released from the burning of raw materials 2 The pollution to the environment is extremely serious