Photocatalytic application of defective WO<inf>3</inf> nanoparticles for precious metal recovery from plating effluent
Issued Date
2024-02-01
Resource Type
ISSN
18761070
Scopus ID
2-s2.0-85180266913
Journal Title
Journal of the Taiwan Institute of Chemical Engineers
Volume
155
Rights Holder(s)
SCOPUS
Bibliographic Citation
Journal of the Taiwan Institute of Chemical Engineers Vol.155 (2024)
Suggested Citation
Hunsom M., Kunthakudee N., Sangkhanak S., Serivalsatit K. Photocatalytic application of defective WO<inf>3</inf> nanoparticles for precious metal recovery from plating effluent. Journal of the Taiwan Institute of Chemical Engineers Vol.155 (2024). doi:10.1016/j.jtice.2023.105301 Retrieved from: https://repository.li.mahidol.ac.th/handle/123456789/95849
Title
Photocatalytic application of defective WO<inf>3</inf> nanoparticles for precious metal recovery from plating effluent
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Corresponding Author(s)
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Abstract
Background: Plating units of electronics industry generally release wastewater with various types of metal ions and sometimes precious metal ions such as gold. Discharging of gold-containing wastewater is an economic loss. Accordingly, the photocatalytic process has emerged as the effective process to recover gold ions. Methods: The defective WO3 NPs were synthesized by sequential process of acid precipitation and annealing method to recover gold from a cyanide-free plating bath solution. The impacts of annealing temperatures and operating conditions on the photocatalytic property and activity of WO3 NPs were explored. Significant findings: An annealing temperature in the range of 650 – 950 °C did not significantly affect the surface property of the WO3 samples, but remarkably impacted the optical property. A high temperature induced the generation of W5+ and oxygen vacancies in the WO3 structure, promoting the visible light response. Among all synthesized samples, the WO3 sample annealed at 850 °C (W85) exhibited the superior photocatalytic activity to recover gold up to 90.8 % at photocatalyst loading of 2 g/L, initial pH of effluent of 9.2, C2H5OH concentration of 10 vol.% in the presence of 6 mM Na2S2O3. In addition, the W85 sample possessed consistent stability to recover gold from the plating effluent even at the 5th cycle.