Process for leaching rare earth from ion-adsorption type rare earth ore without using ammonium salt

Abstract

A process for leaching rare earths from non-ammonium salts of ion-adsorption rare earth ores, using a mixture of calcium, magnesium, and sodium salts as a leaching agent, and using non-ammonium salts such as calcium hydroxide, magnesium hydroxide, or sodium hydroxide as a precipitating agent , replacing ammonium-containing salts, the present invention fundamentally solves the problem of ammonia nitrogen pollution in the mining of ion-adsorbed rare earths, and realizes green and environmentally friendly mining of ion-adsorbed rare earths, which is a process with greater economic and social benefits.

Description

technical field [0001] The invention relates to a process for leaching rare earths from non-ammonium salts of ion-adsorption rare earth ores. Background technique [0002] The mining of ion-adsorption rare earth mines in my country has a history of several decades. At the beginning of mining, the pool leaching process of sodium chloride was used as the leaching agent. Later, because sodium chloride would make the soil salinized, it was changed to ammonium sulfate. The leaching agent forms a mining process for ion-absorbing rare earths with ammonium sulfate as the leaching agent and ammonium bicarbonate as the precipitating agent, and gradually develops from the pool leaching process to an in-situ leaching process that protects the ecology. However, for a long time, the process of using ammonium sulfate as the leaching agent and ammonium bicarbonate as the precipitating agent has lost a large amount of ammonium ions no matter during mining or in the ore body after mining rare ...

AI Technical Summary

Problems solved by technology

However, for a long time, the process of using ammonium sulfate as the leaching agent and ammonium bicarbonate as the precipitating agent has lost a large amount of ammonium ions no matter in the mine mining or in the ore body after the rare earth mining, causing the surrounding environment of the mine to be polluted and the water body to be polluted. Ammonia nitrogen seriously exceeds the standard (ammonia nitrogen content in mining wastewater is 100-400mg / L), so far it cannot be treated up to the standard, leaving long-term environmental pollution problems