Method for decomposing and extracting Baotou rare earth ore through mixed alkali roasting process

Abstract

The invention relates to a clean production process for extracting rare earth from Baotou rare earth concentrate. The present invention is carried out according to the following steps: firstly, Baotou rare earth concentrate is subjected to chemical dressing to remove calcium and iron and then dried; Mix at 1:0.2~0.3, roast at 500~550°C for 1~2 hours; then wash with water to remove fluorine and phosphorus; To obtain cerium-rich ore; then use industrial hydrochloric acid to dissolve the cerium-rich ore in the presence of a reducing agent and remove impurities to produce a cerium chloride solution, which is precipitated by ammonium bicarbonate and burned to obtain cerium oxide. Baotou rare earth mine is treated by the method of the present invention, and the effect of removing fluorine and phosphorus is good; it solves and avoids the large amount of "three wastes" produced by "concentrated sulfuric acid method" and "caustic soda method", and solves the problem of calcium, phosphorus, acid-soluble slag and iron thorium The comprehensive recovery of slag is conducive to the comprehensive utilization of resources.

Description

technical field [0001] The invention belongs to the field of rare earth hydrometallurgy and chemical industry, and relates to a clean production process for extracting rare earth from Baotou rare earth mine. Background technique [0002] The most representative mineral of China's rare earth resources - Baotou Baiyun Obo rare earth mine, its rare earth minerals are mainly composed of bastnaesite and monazite. The mixed rare earth concentrate composed of rock is Baotou rare earth concentrate. Due to the particularity and complexity of its mineral composition, technical processes such as mineral decomposition, transformation and separation are quite difficult. There are no such minerals abroad, and there is no similar extraction and separation technology. [0003] The fastest growing rare earth industry is rare earth permanent magnet materials, and rare earth permanent magnet materials have the highest value among rare earth products. In light rare earth resources, the valu...

AI Technical Summary

Problems solved by technology

The commonly used "high-temperature concentrated sulfuric acid roasting method" or "third-generation concentrated sulfuric acid method" has relatively low production costs and strong adaptability of raw materials, but there are large amounts of "three wastes", which easily cause serious pollution to the surrounding environment, and are difficult to treat. Defects such as high cost

At the same time, because thorium, a precious resource in minerals, is roasted with concentrated sulfuric acid to produce thorium pyrophosphate, which is difficult to recycle, and is dispersed in the waste residue, which is difficult to recycle and treat, resulting in the waste of this precious resource

On the other hand, the "caustic soda method" production process is limited by the grade and composition of rare earth ores, and the energy consumption in the production process is too high, so there are few enterprises using alkaline decomposition and other smelting processes

Images