Structural Modification Of Co And Cu Electrodeposits In Electrorefining Process

Cobalt is widely used in ceramic industry,battery industry and aerospace industry due to its ferromagnetism,ductility and excellent mechanical properties.Copper has excellent conductivity,thermal conductivity and ductility,which is widely used in electrical,electronic technology,motor manufacturing and other industrial sectors.No matter in the production of industrial pure cobalt and copper or high-purity metal cobalt and copper,electrolytic refining is an important means to convert metal ions into metals or to put forward metal purity.However,in the process of electrorefining,hydrogen evolution and dendrite growth will lead to loose and porous structure of the product,which will lead to the coating and aggregation of electrolyte and impurities and reduce the purity and quality of the product.In view of these problems encountered in the electrorefining process of cobalt and copper,two kinds of external physical fields,micro bubble flow and magnetic stirring,were introduced in this study to control the electrorefining process and products.The main results are as follows:Micro bubble flow and magnetic stirring plus physical field can effectively accelerate the diffusion and mass transfer process of electroactive substances in the process of electrorefining,and can effectively promote the desorption of hydrogen from the matrix,reducing its impact on the electrorefining products.The external physical field can transform the nucleation process from continuous nucleation to instantaneous nucleation,and grow in the form of spiral dislocation.However,the physical field does not change the instantaneous nucleation mode,but it can also promote the growth of crystal nucleus and avoid the formation of secondary crystal nucleus.Under the action of external physical field,the loose and porous structure caused by dendrite growth in the electrorefining process of cobalt and copper is avoided,and the smooth and dense electrorefining products are formed.The change of nucleation and growth mode during Electrorefining of cobalt results in the formation of strong preferred orientation of(110)crystal plane and columnar crystals parallel to and perpendicular to the matrix.In the process of electrolytic refining copper,the grain size of the product is better developed.Dense electrodeposited copper and cobalt products and their larger grain size can effectively reduce the probability of electrolyte and impurities wrapping and gathering on the defects and grain boundaries,which is helpful to improve the quality and purity of products.