Method for extracting lithium from lithium ore leaching residues

Abstract

The invention relates to the technical field of metal smelting, and particularly provides a method for extracting lithium from lithium ore leaching residues, which comprises the following steps: uniformly mixing the dried leaching residues with a sulfate additive, and grinding and activating the mixed first material; mixing the activated first material with concentrated sulfuric acid, carrying out heat treatment on the mixed second material, and spraying a calcium agent in the heat treatment process to fix aluminum; carrying out water leaching or acid leaching on the third material subjected to heat treatment to extract lithium; and recycling the lixivium subjected to lithium extraction for leaching of a third material, adding hydrogen peroxide and sodium hydroxide into the lixivium subjected to lithium extraction to precipitate aluminum and iron impurities, removing the impurities through solid-liquid separation, adding sodium carbonate into the lixivium, and then separating a solid-liquid mixture to obtain lithium carbonate, the lithium precipitation residual liquid is directly used for leaching a third material or mixed sulfate is obtained through evaporative crystallization for reuse. According to the scheme, the lithium leaching rate of the lithium ore leaching residues is gt; the concentration of aluminum ions in the leachate is 1t; the lithium comprehensive recovery rate gt is 0.5 g / L; and the lithium resource in the lithium leaching residue is effectively recovered.

Description

technical field [0001] The invention relates to the technical field of metal smelting, in particular to a method for extracting lithium from lithium ore leaching slag. Background technique [0002] The main mineral raw materials for preparing lithium are spodumene (containing Li2O5.8%-8.1%), lepidolite (containing Li2O3.2%-6.45%), and lepidolite (containing Li2O7.1%-10.1%) , Lithium feldspar (containing Li2O2.9% ~ 4.8%) and lepidolite (containing Li2O1.1% ~ 5%), of which the first three minerals are the most important. The process of extracting lithium from lithium ore includes roasting transformation-water leaching method, sulfuric acid method, sulfate method and limestone method. Lithium salt is obtained by roasting lithium ore and sulfuric acid, sulfate or lime, and then dissolving, filtering and purifying. Roasting transformation-water leaching method is suitable for the extraction of lithium from spodumene and hectorite. The ore is first roasted at high temperature to...

AI Technical Summary

Problems solved by technology

[0003] However, methods such as roasting transformation-water immersion method, sulfuric acid method, sulfate method and limestone method are used to extract lithium from lithium ore. The lithium leaching rate in the ore is less than 80%, and the lithium oxide content in the leaching residue is generally greater than 0.5%. It has significant economic development value, and there is currently no public or operational engineering technology scheme for the extraction of lithium from leaching residues

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