Recovery of tin and copper by recycling of printed circuit boards from obsolete computers

Abstract

-This paper presents the experimental results for the leaching of printed circuit boards (PCB) from obsolete computers for extracting and recovering tin and copper by means of leaching followed by precipitation. Printed circuit boards were dismantled, cut into small pieces, and fed into a cylinder mill. The powder obtained was leached by using the aqueous solutions 2.18N H 2 SO 4 , 2.18N H 2 SO 4 + 3.0N HCl, 3.0N HCl, and 3.0N HCl + 1.0N HNO 3 . The lowest values for the percentage of metal extraction were obtained with 2.18N H 2 SO 4 (2.7% for Sn and lower than 0.01% for Cu), while the 3.0N HCl + 1.0N HNO 3 leach system exhibited an extraction of 98% for Sn and 93% for Cu. Precipitates were obtained at different pH values by neutralizing the leach liquors using NaOH. The 3.0N HCl + 1.0N HNO 3 leach system presented the highest recovery values from the powder feed (84.1% for Sn and 31.9% for Cu), as well as from the leach liquor (85.8% for Sn and 34.3% for Cu).

Waste Printed Circuit Boards recycling: an extensive assessment of current status

“…A number of articles have been published in recent years pertaining to the leaching of copper from waste PCBs (Castro and Martins, 2009;Koyama et al, 2006;Masavetas et al, 2009;Md Fazlul et al). Copper can effectively be leached using acidic or ammoniacal media (Behnamfard et al, 2013;Havlik et al, 2010;Kamberović et al, 2009;Koyama et al, 2006;Masavetas et al, 2009;Oh et al, 2003).…”

“…Tin leaching using different inorganic acids was studied in detail with the objective of recovering Cu and Sn (Castro and Martins, 2009). They could achieve maximum 89.1% and 98.1% Sn recoveries in 2h at 60 ⁰ C using 3N HCl and (3N HCl + 1N HNO 3 ) leach system respectively.…”

Pelarutan Selektif Tembaga dari Limbah Printed Circuit Board dengan Hidrogen Peroksida

“…Tembaga yang berhasil dipisahkan sebesar 82% setelah pelarutan selektif selama 4 jam. Castro and Martins (2009) memisahkan tembaga dari limbah PCB dengan menggunakan pelarutan selektif serbuk PCB dalam larutan H2SO4 2,18 N dan HCl 3 N yang berhasil memisahkan tembaga masing-masing sebesar < 0,01% dan 33,2%. Tembaga juga dapat dipisahkan dengan metode pelarutan selektif menggunakan campuran H 2 SO 4 4 M dan 20 mL H 2 O 2 30% selama 3 jam dengan pengadukan 300 rpm .…”

Optimization of HNO3 leaching of copper from old AMD Athlon processors using response surface methodology

“…The technological advancement lead the world to a digital future. The waste of electrical and electronics equipment are increasing from 40 to 70 million tones/year [1,2]. Electronic waste contains precious metals as well as base metals.…”

“…During hydrometallurgical process, leaching rates of metals are effected by the kind of leaching agent, concentration and temperature [10,11]. Different chemicals can be used as leaching agents like cyanides [12][13][14], sulfuric acid, aqua regia, thiourea [14][15][16], thiosulfate and their mixtures with other chemicals [17][18][19][20][21][22].…”