Separation of manganese and nickel from tantalum capacitor leach liquor- A comparative study of D2EHPA and CYANEX272 as extractant

Abstract

Tantalum capacitor is widely distributed in almost every electronic equipment due to its superior volumetric efficiency, which allows miniaturization of size of the gadgets- a prime demand of today’s technological driven society. These capacitors, after reaching the end-of-life stage, should be considered as a rich secondary resources for recovery of different valuable metals. In these work, we have developed a hydrometallurgical method for recovery of manganese and nickel from tantalum capacitors leach liquor. Firstly, the capacitors were subjected to preprocessing treatment for removal of outer mold housing containing epoxy resin with silica. After this, the metal-rich fraction was subjected to leaching using hydrochloric acid to selectively dissolve all the manganese and nickel into the solution. This leach liquor was then subjected to solvent extraction using D2EHPA and CYANEX272 to study the effectiveness of these carrier in separation of manganese from nickel and other minute metals. Both the carrier shows excellent selectivity for separation of manganese from other metallic elements. Extraction efficiency of manganese was 97% and 99% for D2EHPA and CYANEX272, respectively.