Removal of Hazardous Metals from Waste Printed Circuit Boards by Chemical and Biological Methods

A printed circuit board, or PCB, is used to mechanically support and electrically connect various electronic components by using conductive tracks etched from copper sheets laminated on to a nonconductive substrate. The material composition of PCB is 40% of metals, 30% of ceramics and 30% of plastics. Since the PCB contains higher percentage of metals which are hazardous when discarded to the ecosystem the metals must be removed. The objective of the study is to remove hazardous metals from PCB by biological and chemical treatment methods. PCBs are collected from waste electrical and electronic equipment. The study is carried out for both economic and ecological reasons. The biological study involves the removal of hazardous metals by biological leaching process by using the fine powder obtained from the seed of "Persia Americana" commonly called as AVOCADO (butter fruit). The seed is powdered and processed which is used for removing the hazardous metals present in the waste PCB. In chemical method, the fine powder of discarded PCB is leached with mixed acids for the removal of hazardous metals from PCB. Thus both the methods were studied to achieve an eco-friendly technique.