Pyrolysis Pre-treatment of PCBs: A Sustainable Solution to Convert Encapsulation into Marketable Product and Separation of Metallic Concentrate

Abstract

Printed circuit boards (PCBs) are the essentially required component of all the electronic goods, containing a variety of metals. PCBs are made up of several layers of epoxy resins, thin metallic sheets, etc. The metallic sheet encapsulated with resin hinders the hydrometallurgical metal dissolution process. The mechanical pre-treatment process is not feasible due to high energy consumption and non-availability of a compatible machine. Therefore, pyrolysis studies were conducted for the removal of capsulation of resin on metals present in PCBs. Various experimental parameters were studied to optimize the pyrolysis process. The gas generated during the pyrolysis was condensed to get Low Density Oil (LDO).And the metal depleted poly-cracked carbon was converted to activated carbon and the metallic fractions processed for metal recovery using hydrometallurgy. The process has potential for commercialization after feasibility studies.