Title: Application of polymer inclusion membrane to recover nickel and gold: A method to complement hydrometallurgical recycling of waste printed circuit boards
The work entails applying Polymer Inclusion Membrane (PIMs) to complement a distinct hydrometallurgical route of electronic waste (e-waste) recycling to recover trace metals otherwise ignored. The existing methods are being utilized for the recovery of gold, silver, copper. However, many metals such as nickel, zinc, lead, etc. pose contaminations to these recovered metals. This research is a complementary method to make it possible to remove these contaminations for the complete recovery of metals with high purity. Vast quantities of waste of electric and electronic equipment have been produced due to continuous technological revolution. Waste printed circuit boards (WPCBs) are the heart of these electronic components. WPCBs contain valuable metals such as gold, silver, copper, nickel with richer concentrations and hazardous and environmental pollutants, which make their recycling a vital subject in both aspects of waste treatment and the extraction of valuable metals. Researchers have established many efficient recovery methods such as cementation, recrystallization, chemical precipitation, ion exchange, and solvent extraction, but still, recovery of metals in a lower concentration such as palladium, platinum, nickel, zinc, and lead remains a global issue. This research proposal focuses on the hydrometallurgical route, employing Polymer Inclusion Membrane (PIMs) to separate and recover these valuable metal ions of lower concentration. These membranes may also be utilized as an intermediate process for removing toxic/heavy elements from WPCBs leach liquor to make the solution richer with precious metals.
PIMs are environmentally friendly for the separations of heavy and toxic metals from aqueous solutions. They can be a better alternative (in terms of cost, long-term stability, selective separations of metal ions) than ion exchange and other liquid-liquid extraction methods as these membranes can simultaneously conduct extraction and stripping (back extraction). Development in PIMs technology for recycling WPCBs can pace up the commercialization process and make it feasible for industrial practice for metal production from secondary resources like WPCBs.
The main objectives of this project are:
Synthesis and characterization of suitable Polymer Inclusion Membrane(PIMs).
 Application of PIMs for copper, gold, nickel, recovery from WPCBs leach liquor.
To evaluate its applicability for removing/separating contaminations (heavy/toxic elements) from other Conventionally (ion exchange, solvent extraction) recovered metal such as gold, copper.
To evaluate the economic and environmental viability of PIMs.
To evaluate the industrial feasibility of PIMs.