High-resolution continuum source graphite furnace atomic absorption spectrometry determination of ecotoxic and precious metals in printed circuit boards of waste mobile phones after selective sorption

Abstract

Waste printed circuit boards (PCBs) contain high amounts of valuable precious metals (PMs) as well as ecotoxic elements (TE). Recycling waste PCBs enables the recovery of precious metals minimize harm to the environment caused by discarded electronics.This study established a benign and effective process for selective recovery of Au, Pt, Pd and ecotoxic elements such as As, Cd, Cr, Pb, Sb from waste PCBs. Pre-treating waste PCBs with a mixture of HCl and H2O2 in autoclave was fast and efficient decomposition. In order to recover PMs and TE from obtained PCB solutions, two sorbents were synthesized. 0.1 M HCl is sufficient for extraction of 96–100 % of TE and 3 M HCl is used for extraction of 100 % of PMs from PCB-solutions. The developed approach of transferring analyte into a solution is characterized as highly productive and make it possible to avoid any impact of matrices upon selectivity extraction and to determine analyte with high accuracy.The concentrations of analytes in five PCB samples were found in range of 10−6 - 10-1 % wt by HR-CS GFAAS method. HR-CS-GFAAS limits of determination and upper limits of analyte content determination were (μg·mL-1) 0.0008 and 0.1 (Au); 0.0008 and 0.1 (Pd); 0.001 and 0.8 (Pt); 0.0005 and 0.3 (As); 0.00006 and 0.01 (Cd); 0.0002 and 0.03 (Cr); 0.0005 and 0.1 (Pb); 0.0005 and 0.25 (Sb).The obtained data will be useful for the development of processes for the recycling of analytes from waste mobile phones.