Recovery of gold from electronic wastewater by Phomopsis sp. XP-8 and its potential application in the degradation of toxic dyes

Environmentally friendly, efficient, and economical methods of gold recovery are significant challenges for high-tech industries and environmental protection. In this study, Phomopsis sp. XP-8, a filamentous endophytic fungus, demonstrated great potential for selectively recovering gold from electronic wastewater without any pretreatment and was shown to be convenient and safe in practical application. Under optimum conditions, the gold recovery rate was more than 80% at a dilute concentration of Au³⁺. Model-fitting analysis indicated the adsorption of Au³⁺ was well described by the pseudo-second-order kinetic model and the Langmuir isotherm model. The maximum Au³⁺ adsorption was from 208 to 280 mg/g within the temperature range of 20–50 °C. The data from electronic wastewater revealed its great potential for selective recovery of gold from complex aqueous solutions. Additionally, the formed nanogold-bioconjugates exhibited efficient degradation of toxic dyes in wastewater, which demonstrated the potential application of these byproducts produced via the biosorption process.