Highly efficient ZnO/WO<inf>3</inf> nanocomposites towards photocatalytic gold recovery from industrial cyanide-based gold plating wastewater
Issued Date
2023-12-01
Resource Type
eISSN
20452322
Scopus ID
2-s2.0-85180180925
Pubmed ID
38123788
Journal Title
Scientific Reports
Volume
13
Issue
1
Rights Holder(s)
SCOPUS
Bibliographic Citation
Scientific Reports Vol.13 No.1 (2023)
Suggested Citation
Sangkhanak S., Kunthakudee N., Hunsom M., Ramakul P., Serivalsatit K., Pruksathorn K. Highly efficient ZnO/WO<inf>3</inf> nanocomposites towards photocatalytic gold recovery from industrial cyanide-based gold plating wastewater. Scientific Reports Vol.13 No.1 (2023). doi:10.1038/s41598-023-49982-6 Retrieved from: https://repository.li.mahidol.ac.th/handle/20.500.14594/95544
Title
Highly efficient ZnO/WO<inf>3</inf> nanocomposites towards photocatalytic gold recovery from industrial cyanide-based gold plating wastewater
Corresponding Author(s)
Other Contributor(s)
Abstract
Discharging the gold-contained wastewater is an economic loss. In this work, a set of ZnO/WO3 was facile synthesized by hydrothermal method in order to recover gold from the industrial cyanide-based gold plating wastewater by photocatalytic process. Effect of ZnO contents coupled with WO3 was first explored. Then, effects of operating condition including initial pH of wastewater, type of hole scavenger, concentration of the best hole scavenger and photocatalyst dose were explored. A series of experimental results demonstrated that the ZnO/WO3 nanocomposite with 5 wt% ZnO (Z5.0/WO3) depicted the highest photocatalytic activity for gold recovery due to the synergetic effect of oxygen vacancies, a well-constructed ZnO/WO3 heterostructure and an appropriate band position alignment with respect to the redox potentials of [Au(CN)2]− and hole scavengers. Via this ZnO/WO3 nanocomposite, approximately 99.5% of gold ions was recovered within 5 h using light intensity of 3.57 mW/cm2, catalyst dose of 2.0 g/L, ethanol concentration of 20 vol% and initial pH of wastewater of 11.2. In addition, high stability and reusability were observed with the best nanocomposite even at the 5th reuse. This work provides the guidance and pave the way for designing the ZnO/WO3 nanocomposite for precious metal recovery from a real industrial wastewater.