Synthesis of polymetallic nanoparticles from printed circuit board waste and application in textile dye remediation

In this work, polymetallic nanoparticles were synthesized from printed circuit boards waste (PN-PCBs) through chemical reduction. The Transmission Electron Microscopy analyzes proved that the PN-PCBs have a spherical morphology with a diameter of approximately 30 nm. The energy-dispersive X-ray spectroscopy showed that the PN-PCBs consist mainly of Cu, Fe, Zn, and Ni. However, only diffraction peaks characteristic of Cu degrees and Cu2O were observed in the X-ray diffraction pattern. The surface area, pore volume and pore size of the nanoparticles, determined by nitrogen adsorption and desorption isotherms, were equal to 693 m(2) g(-1), 3.99 cm(3) g(-1) and 3.12 nm, respectively. The PN-PCBs was applied in the removal of the textile dye reactive blue 4 (RB4). The RB4 removal is lower at extreme pH values, i.e. at pH 2 and 8. In the pH range between 4 and 10, the removal is practically the same. The removal capacity of RB4 was favored in the nanoparticle dosage of 0.40 g L-1 and in the dye concentration of 400.0 mg L-1. The results were better adjusted to the pseudo-second order kinetic model and the Langmuir adsorption isotherm, and the RB4 removal capacity was 556 mg g(-1). These results show that PN-PCBs can be used in processes decontamination with high removal rates.