Selective Recovery of Gold from Electronic Waste by New Efficient Type of Sorbent.

Abstract

Modular connectors are applied by computer users, and they can be metallic secondary sources containing metals such as gold and copper. Because gold is a micro-component, the solution obtained after the pin digestion contains a low concentration of gold(III) ions, and efficient and selective sorbent should be used for gold(III) ion recovery. The selective removal of small amounts of gold(III) from 0.001-6 M hydrochloric acid solutions using pure and solvent-impregnated macroporous polystyrene crosslinked with divinylbenzene sorbents (Purolite MN 202 and Cyanex 272) is presented. Gold(III) ions were recovered effectively from the chloride solution after the digestion of the modular connector RJ 45 (8P8C) using Purolite MN 202 after the impregnation process. The dependence of the recovery percentage (R%) of gold(III) on the contact time was determined. The highest value of gold(III) ion sorption capacity (259.45 mg·g-1) was obtained in 0.001 M HCl for Purolite MN202 after the Cyanex 272 impregnation. The results can be applied to gold recovery from e-waste. The presented method of gold recovery does not generate nitrogen oxides and does not require the use of cyanides.