Research progress of copper extraction from low-grade oxidized copper ore with high alkalinity gangue

Low-grade oxidized copper ore with high alkaline gangue is regarded as "three high and one low" refractory one, with the characteristics of high contents of calcium and magnesium, high mud content, high oxidation rate and low copper grade. This paper sums up its resource characteristics, leaching methods and the extraction of copper from leaching solution. The main leaching methods include flotation, ammonia leaching and bacterial leaching. The main extracting methods include extraction, ion exchange, precipitation. Ammonia leaching and ammonia-producing bacteria leaching can be used for leaching effectively and economically. However, the volatility of ammonia of the former and cultivation problems of the latter make them imperfect. Therefore, low concentration ammonia leaching-extraction or ammonia-producing bacteria leaching-extraction system may be the direction in the future.