Biological upcycling of nickel and sulfate as electrocatalyst from electroplating wastewater

作者：Fu, Xian-Zhong; Yang, Yu-Ru; Liu, Tian^*; Guo, Zhi-Yan; Li, Chen-Xuan; Li, Hai-Yang^*; Cui, Kang-Ping; Li, Wen-Wei^*

来源：Water Research, 2024, 250: 121063.

DOI：10.1016/j.watres.2023.121063

• Electroplating wastewater
• Biogenic nanomaterials
• Electrocatalyst
• Upcycling
• Nickel
• Sulfate reduction

Upcycling nickel (Ni) to useful catalyst is an appealing route to realize low-carbon treatment of electroplating wastewater and simultaneously recovering Ni resource, but has been restricted by the needs for costly mem-branes or consumption of large amount of chemicals in the existing upcycling processes. Herein, a biological upcycling route for synchronous recovery of Ni and sulfate as electrocatalysts, with certain amount of ferric salt (Fe3+) added to tune the product composition, is proposed. Efficient biosynthesis of bio-NiFeS nanoparticles from electroplating wastewater was achieved by harnessing the sulfate reduction and metal detoxification ability of Desulfovibrio vulgaris. The optimal bio-NiFeS, after further annealing at 300 degrees C, served as an efficient oxygen evolution electrocatalyst, achieving a current density of 10 mA & sdot;cm  1 at an overpotential of 247 mV and a Tafel slope of 60.2 mV & sdot;dec  1. It exhibited comparable electrocatalytic activity with the chemically-synthesized counterparts and outperformed the commercial RuO2. The feasibility of the biological upcycling approach for treating real Ni-containing electroplating wastewater was also demonstrated, achieving 99.5 % Ni2+removal and 41.0 % SO42  removal and enabling low-cost fabrication of electrocatalyst. Our work paves a new path for sus-tainable treatment of Ni-containing wastewater and may inspire technology innovations in recycling/ removal of various metal ions.

• 单位
  中国科学院