COPPER EXTRACTION FROM SCRAP CABLES BY BIOTECHNOLOGICAL MEANS

摘要

We report on laboratory results regarding bioleaching of metallic copper from waste cables derivedfrom recycling of end-of-life vehicles. The copper has been met as irregular-shaped wires oftencoated with tin. The complex nature of the material and the non-uniform shape of the wires arerendering copper recovery by gravity separation inefficient. Bacterially assisted leaching with mixedconsortium of mesophylic micro-organisms has been tried for ultimate recovery of the copperremaining after gravity separation. Continuous adaptation of the cultures to the substrate has beenenvisaged in order to guarantee sufficient degree of ferric iron regeneration by bacteria duringleaching. It has been established, that under optimal leaching conditions such as pulp density andpH it is possible to recover nearly 98 per cent of the copper in solution within reasonable time. Thelow impurity composition of the copper containing PLS makes it suitable for further processing bysolvent extraction.