A method for leaching gold and silver from manganese-coated gold and silver ore under normal temperature and pressure

Abstract

The invention discloses a method for leaching gold and silver out of kustelite wrapped by manganese under normal pressure and temperature. The method includes the steps that raw ore grinding is performed; pretreatment is performed through sulfuric acid and reduced iron powder; filtering is carried out; and manganese-leaching slag obtained through filtering is subjected to cyanide leaching to obtain the gold and silver. Compared with existing methods for leaching the gold and silver out of the kustelite wrapped by the manganese, the method achieves pretreatment of the kustelite wrapped by the manganese under low acid concentration and normal pressure and temperature, the gold and silver leaching rate is substantially increased, and the method is applicable to the kustelite wrapped by the manganese.

Description

technical field [0001] The invention relates to a beneficiation method for manganese-encapsulated gold and silver ore, more specifically, to a pretreatment and leaching method for manganese-encapsulated gold and silver ore. Background technique [0002] Manganese-silver ore contains high manganese minerals and other oxides, and gold and silver are often dispersed in these minerals in very fine particles, making manganese-silver ore one of the most difficult silver-containing minerals to handle. When cyanide is used for direct leaching, since most of the gold and silver are wrapped, cyanide cannot effectively contact it, so the leaching rate of gold is generally less than 50%, and the leaching rate of silver is even less than 30%. [0003] There are many researches on the chemical leaching of manganese minerals at home and abroad. There are three possible schemes for leaching manganese-silver ores: first leaching manganese and then leaching silver, direct leaching silver (or ...

AI Technical Summary

Problems solved by technology

This theoretically shows that the two-mine method must be heated under a higher sulfuric acid concentration to realize the leaching of manganese, so that the wrapped gold and silver are exposed; Jiang Tao et al. ,1995,06:26-29+50-51) proposed to use RH for one-step treatment of silver-manganese ore, which has the advantages of short process, high speed, and low investment; in the leaching process, part of RH acts as a reducing agent, and part of it acts as a reducing agent. With a catalyst, the entire leaching reaction is carried out step by step. The reduction of manganese dioxide can be completed quickly, while the oxidation reaction of silver takes a certain amount of time. Since the intermediate product is easy to volatilize, it is necessary to control the speed of the previous reaction to ensure the synchronization of the two reactions. To ensure the leaching rate of silver, the process condition test shows that RH and H 2 SO 4 When the dosage is 13.2% and 36%, the time is 2 hours, and the liquid-solid ratio is 4:1, the leaching rates of manganese and silver can reach 96% and 79%, respectively. This scheme realizes the simultaneous leaching of manganese and silver without sulfuric acid The dosage is too high, the cost is high, and there are difficulties in production and implementation

[0005] Generally speaking, scientific and technological workers have carried out a lot of research work on manganese-silver ore, and technically realized the pretreatment of manganese-silver ore, and the leaching indicators of manganese and silver are also high. However, due to factors such as complex process and large consumption of chemicals, Existing research results cannot be practically applied to manganese-silver ore for a long time

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