A Review of the Current State of Research on Gallium Recovery from Bayer Liquor

This paper provides an overview of methods used to recover gallium from Bayer liquors, highlights and analyzes shortcomings of the current state of research, and predicts the direction of recovery processes in the future. Currently, techniques for recovering gallium from Bayer liquor can be classified as resin ion exchange, solvent extraction, precipitation, and electrochemical. Compared with other recovery methods, the precipitation method is inexpensive but suffers from disadvantages regarding the relatively complex procedures and poor recovery results. Electrochemical methods do not change the solution composition but suffer from low electrolysis efficiency and high mercury content. Solvent extraction methods are simple to operate but complex to separate effectively because of low gallium concentrations. The resin ion exchange method has become the primary method of gallium recovery from Bayer liquor due to its simple operation, high recovery efficiency, and low contamination. Recently, researchers have discovered more efficient methods for recovering gallium based on resin ion exchange: impregnated resin methods and ion blotting. The impregnated resin method combines high adsorption efficiency with extractant selectivity but still suffers from extractant loss problems. Ion impregnation has the advantage of specific adsorption of target ions in complex systems, and its preparation process is improving, which will be a new research hotspot in the future.