Method for preparing manganese sulfate solution through direct reduction leaching of manganese oxide ores

Abstract

The invention discloses a method for preparing manganese sulfate solution through direct reduction leaching of manganese oxide ores. The method comprises the steps of (1) pre-reduction: adding manganese oxide ore powder in water or dilute sulfuric acid for pulping so as to obtain pulp liquid, gradually adding concentrated sulfuric acid in the pulp liquid, maintaining the temperature of the reaction system, carrying out stirring reaction, and adding manganese sulfate for continuous stirring so as to prepare pre-reduced ore pulp; (2) reduction and acid leaching: preparing dilute sulfuric acid solution, adding the pre-reduced ore pulp and a reducing agent in the dilute sulfuric acid solution, maintaining the temperature of the reaction system, and carrying out stirring reaction to prepared manganese sulfate leaching liquid; and (3) solution purification: adding a neutralizer and an oxidant in the manganese sulfate leaching liquid, carrying out filter to prepare primary purified liquid, and adding a vulcanizing agent and polyacrylamide in the primary purified liquid for filter so as to obtain the manganese sulfate solution. The method has the beneficial effects of overcoming the defects in the prior art, simplifying the production process, reducing the material consumption in the reduction process, improving the manganese reducing and leaching rate, decreasing the waste residue yield and reducing the leaching cost.

Description

technical field [0001] The invention relates to a method for preparing manganese sulfate solution, in particular to a method for preparing manganese sulfate solution through direct reduction leaching of manganese oxide ore. Background technique [0002] Manganese sulfate is a basic manganese salt, which is widely used in metallurgy, chemical industry, battery, feed and other industries. It is the basis for the preparation of high-purity manganese sulfate, nickel-cobalt-manganese ternary materials such as electrolytic metal manganese, electrolytic manganese dioxide, and trimanganese tetraoxide. raw materials. [0003] Manganese sulfate is generally prepared from rhodochrosite through sulfuric acid leaching, neutralization and iron removal, solid-liquid separation, and deep impurity removal. However, with the massive development of resources, the grade of rhodochrosite is gradually depleted, the material consumption increases, the amount of slag increases, the burden of envir...

AI Technical Summary

Problems solved by technology

The one-step method of the two mines takes a long time to react, the reaction system needs to be heated to above 90°C for a long time, the consumption of reducing agent pyrite is large, the iron content in the leaching solution is high, the iron removal is difficult, the solid-liquid separation is difficult, the amount of slag is large, and the use value of waste slag is high. Low, there is a risk of secondary pollution, so far only a few companies use it

[0013] During the reaction process of sulfur dioxide and sulfite leaching, the regulation of the pH value is highly required. When the pH value is too low, the utilization rate of the reducing agent is low, and the by-product of manganese dithionate will inevitably be produced in the reaction process. The quality of the solution has a great influence

The ferrous sulfate leaching method and the iron filings leaching method have fast reaction speed and low requirements on the temperature of the reaction system. The leaching effect of manganese in the ore is relatively ideal. The disadvantages are basically the same as the two-mine one-step method

Biomass leaching, glucose leaching, waste molasses leaching, and other organic reducing agent direct reduction leaching methods all have the disadvantages of long reaction time, high acid consumption, and high organic residues in manganese sulfate solution, which cannot be put into practical application for the time being.

[0014] To sum up, the maturity of manganese oxide ore direct reduction leaching technology is not yet able to meet the actual production needs, and the industry's technical demand for this direction is still relatively urgent