title: Printed circuit board recycling: Physical processing and copper extraction by selective leaching.
abstract: Global generation of waste electrical and electronic equipment (WEEE) is about 40 million tons per year. Constant increase in WEEE generation added to international legislations has improved the development of processes for materials recovery and sustainability of electrical and electronic industry. This paper describes a new hydrometallurgical route (leaching process) to recycle printed circuit boards (PCBs) from printers to recover copper. Methodology included PCBs characterization and a combined route of physical and hydrometallurgical processing. Magnetic separation, acid digestion and chemical analysis by ICP-OES were performed. On leaching process were used two stages: the first one in a sulfuric media and the second in an oxidant media. The results showed that the PCBs composition was 74.6 wt.% of non-magnetic material and 25.4 wt.% of magnetic one. The metallic fraction corresponded to 44.0 wt.%, the polymeric to 28.5 wt.% and the ceramic to 27.5 wt.%. The main metal was copper and its initial content was 32.5 wt.%. On sulfuric leaching 90 wt.% of Al, 40 wt.% of Zn and 8.6 wt.% of Sn were extracted, whereas on oxidant leaching tests the extraction percentage of Cu was 100 wt.%, of Zn 60 wt.% and of Al 10 wt.%. At the end of the hydrometallurgical processing was obtained 100% of copper extraction and the recovery factor was 98.46%, which corresponds to a 32 kg of Cu in 100 kg of PCB.
authors: Department of Chemical Engineering, Polytechnic School of the University of São Paulo, R. do Lago, 250, 05424-970, PO 61548, São Paulo, Brazil. Electronic address: flavia.silvas@gmail.com.
authors: Flávia P C
authors: FP
authors: Silvas
authors: Department of Chemical Engineering, Polytechnic School of the University of São Paulo, R. do Lago, 250, 05424-970, PO 61548, São Paulo, Brazil. Electronic address: monicamariajimenezc@gmail.com.
authors: Mónica M Jiménez
authors: MM
authors: Correa
authors: Department of Chemical Engineering, Polytechnic School of the University of São Paulo, R. do Lago, 250, 05424-970, PO 61548, São Paulo, Brazil; Federal Institute of Technology, Science and Education of Espírito Santo, Rd ES-010, Km 6,5 - Manguinhos, CEP 29173-087 Serra, ES, Brazil. Electronic address: marcospaulo@ifes.edu.br.
authors: Marcos P K
authors: MP
authors: Caldas
authors: Department of Chemical Engineering, Polytechnic School of the University of São Paulo, R. do Lago, 250, 05424-970, PO 61548, São Paulo, Brazil. Electronic address: tavares.vivi@gmail.com.
authors: Viviane T
authors: VT
authors: de Moraes
authors: Department of Chemical Engineering, Polytechnic School of the University of São Paulo, R. do Lago, 250, 05424-970, PO 61548, São Paulo, Brazil. Electronic address: espinosa@usp.br.
authors: Denise C R
authors: DC
authors: Espinosa
authors: Department of Chemical Engineering, Polytechnic School of the University of São Paulo, R. do Lago, 250, 05424-970, PO 61548, São Paulo, Brazil. Electronic address: jtenorio@usp.br.
authors: Jorge A S
authors: JA
authors: Tenório
mesh_terms: D003300:Copper / Q000737:chemistry; D059029:Electronic Waste / Q000032:analysis*; D008669:Metallurgy; D059027:Recycling / Q000379:methods*; D018505:Waste Management / Q000295:instrumentation / Q000379:methods*
chemical_list: D003300:Copper
keywords: Copper; Leaching; Recycling; WEEE