Method for extracting rare earth from weathered crust strain amass type rare earth ore

Abstract

The invention discloses a method for extracting rare earth from weathered crust strain amass type rare earth ore. The weathered crust strain amass type rare earth ore is leached through a leaching agent to obtain rare earth lixivium; then an alkaline calcium compound is added into the rare earth lixivium to carry out impurity removal and sedimentation, and rare earth hydroxide sediment residues are obtained; an organic auxiliary containing solution is adopted for stirring and washing, and the total molar concentration, the liquid-solid ratio, temperature, pH and the like of an auxiliary are controlled; and the auxiliary is combined with calcium in the sediment residues, calcium sulfate in the residues is dissolved, and therefore the final product purity is improved. In addition, through adding of the auxiliary, the auxiliary can return to be used for ore leaching, the function of enhancing leaching is achieved under the acid condition, and the leaching rate of the rare earth is improved. According to the method, ammonia nitrogen pollution is removed, the rare earth leaching rate is increased, meanwhile, formed calcium sulfate in the sediment process of the alkaline calcium compound is reduced, production cost is reduced, and meanwhile products with qualified purity are obtained.

Description

technical field [0001] The invention relates to the field of rare earth hydrometallurgy, in particular to a method for extracting rare earth from weathering crust leaching type rare earth ore. Background technique [0002] Weathering crust leaching-type rare earth minerals are a new type of exogenous rare earth minerals, which were first discovered in Ganzhou, Jiangxi Province, my country in 1969, and are widely distributed in seven southern provinces including Jiangxi, Guangdong, Guangxi, Hunan, Fujian, Yunnan, and Zhejiang. . This kind of minerals has a complete distribution of rare earths, low radioactivity, and is rich in medium and heavy rare earth elements. It is a valuable strategic mineral resource in my country. Its development and utilization enriches medium and heavy rare earth resources, and can solve the problem that traditional endogenous rare earth ores almost only produce light rare earths. [0003] Under normal circumstances, the grade of full-phase rare ea...

AI Technical Summary

Problems solved by technology

For the calcium oxide precipitant, it is a slightly soluble substance, the precipitation reaction is fast, and the precipitation effect is good. However, there are sulfates in the leaching agent of the weathering crust leaching type rare earth ore, resulting in a large amount of sulfate in the leachate. Calcium is used as a precipitating agent, which will produce a large amount of calcium sulfate precipitation in the process of precipitating the ion ore leachate, which also greatly reduces the purity of rare earth concentrate products, and cannot obtain qualified products

Images