Method for extracting aluminum and iron from high iron gibbsite-type bauxite

Abstract

The invention relates to a method for separating and extracting aluminum and iron in bauxite by treating high iron gibbsite-type bauxite by using an alkali medium two-stage wet dissolution process. The primary dissolution of the method comprises the following steps: dissolving out easily dissoluble aluminum component in the high iron gibbsite-type bauxite at low temperature by using a sodium aluminate solution in low alkali concentration, separating liquid from solid, seed-precipitating the primary dissolved solution to obtain an aluminum hydroxide product, and returning the seed-precipitating mother solution for dissolving out the bauxite; the secondary dissolution comprises the following steps: treating primary dissolved slag at a high temperature high-alkaline condition by using an alkali liquor in high molecular ratio or low molecular ratio, feeding aluminum and silicon in the slag into a liquid phase, separating liquid from solid to obtain iron-enriched slag, returning the liquid phase for treating the primary dissolves slag after diluting and removing aluminum and silicone, evaporating and concentrating. The process flow of the method is simple, the separating effect of the iron and the aluminum is obvious so as to respectively obtain aluminum oxide and iron-enriched slag, the iron-enriched slag can be directly used as iron making raw material, and an efficient method for utilizing the high iron bauxite resource in China.

Description

technical field [0001] The invention relates to a method for extracting aluminum and iron from high-iron gibbsite bauxite, in particular to a method for extracting aluminum and iron respectively by two-stage wet stripping in an alkali medium. Background technique [0002] Aluminum is the second largest metal material after steel. It has a wide range of uses, and its correlation with the national economy is as high as 91%. It is a major pillar industry of the country. As the upstream of the aluminum industry, the output of alumina basic raw materials has been growing steadily. In 2012, my country's alumina output reached 37.72 million tons, accounting for more than 1 / 3 of the world's total output. Bauxite is the main raw material for the production of alumina. However, my country's bauxite reserves only account for 1.5% of the world's reserves. According to the current bauxite consumption per ton of alumina production, the guarantee period for my country's bauxite resources i...

AI Technical Summary

Problems solved by technology

[0012] The purpose of the present invention is to overcome the shortcomings of the existing high-iron bauxite iron and aluminum recovery process such as complicated process and high energy consumption, and to provide a technically feasible, economical and reasonable two-stage wet-dissolution of high-iron gibbsite ore with alkali medium. New way to extract aluminum and iron

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