Method for acid-free leaching of cobalt intermediate product from sulfate

Abstract

The invention discloses a method for acid-free leaching of a cobalt intermediate product from sulfate, and aims to solve the technical problems that inorganic acid and a reducing agent need to be added in the leaching process of the cobalt intermediate product, gas pollution is easy to generate, acid leaching liquid needs to be neutralized subsequently to adjust the pH value, the acid and alkali consumption is large, pollutants of ammonia nitrogen or sodium are generated, meanwhile, filtration is difficult, operation efficiency is low, production cost is high, and auxiliary material consumption in the iron removal process of the cobalt leaching solution containing ferrous sulfate is large. According to the method, a solution containing ferrous sulfate is used for leaching the cobalt intermediate product, then solid-liquid separation is carried out, valuable elements such as cobalt and copper are left in filtrate, and impurity elements such as iron and silicon are left in filter residues. According to the method, the cobalt intermediate product can be leached without using inorganic acid such as sulfuric acid and a reducing agent, so that the situation that sulfur dioxide pollutes the environment is thoroughly eliminated, and meanwhile, the cobalt leaching liquid containing ferrous sulfate is used for leaching, so that consumption of alkali is avoided, leaching of the cobalt intermediate product is achieved, and two purposes are achieved.

Description

technical field

[0001] The invention belongs to the technical field of nickel-cobalt hydrometallurgy and cobalt resource recovery, and specifically belongs to a method for leaching cobalt intermediates without acid with sulfate. Background technique

[0002] my country's cobalt resources are scarce, so most of the raw materials of domestic cobalt smelting enterprises need to rely on imports; at the same time, with the rapid development of batteries, hard alloys, industrial catalysis and other industries, my country's cobalt consumption is increasing year by year. Nowadays, for the import of cobalt resources, it is generally first to enrich foreign low-grade cobalt ores into higher-grade crude cobalt intermediates, the main components of which are cobalt hydroxide or cobalt carbonate, and then transport them back to China to process.

[0003] At present, the traditional treatment method for crude cobalt intermediates is to use an acid method for leaching. This method needs t...