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

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 center dot 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.

Automated summary

Modular connectors containing gold and copper are used by computer users. A method to selectively remove trace amounts of gold(III) from hydrochloric acid solutions using sorbents is presented. Gold(III) ions were effectively recovered from the digested modular connector using Purolite MN 202. The highest sorption capacity of gold(III) ions was obtained using Purolite MN 202 after impregnation with Cyanex 272.