Manganese dioxide is used in various devices like electrochemical capacitors, biosensors, batteries, etc.. The presented study contributes to the IRETA 2 project, in which manganese dioxide is a part of the tantalum capacitors and has to be removed to recover tantalum in its pure form. To achieve this goal, an electrochemical dissolution process is proposed based on a range of experiments with parameters pertaining to the complete dissolution of the dioxide from manganese. Based on electrochemical techniques, the performance of the dissolution setup is analyzed experimentally and compared with the literature. The following questions of interest are answered during the study: What is the amount of manganese that can be dissolved electrochemically? Are residues formed in the system? How are the dissolved manganese ions handled further for their recovery? Finally, a method of electrochemical dissolution and a subsequent electrodeposition process is developed. This enables the recovery of manganese in its pure form from the applications of manganese dioxide, promoting an easy and sustainable circular material recycling process.    

The authors gratefully acknowledge the financial support by the Federal Ministry of Education and Research of Germany in the framework of “IRETA 2” (project number: 033RK080H)

Keywords:
Manganese dioxide – electrochemical capacitors – electrochemical dissolution – electrochemical techniques – residues – electrodeposition process – circular material recycling process