(397g) Waste to Resource: Synthesis of Electrolyte and Electrode Material in Vanadium Redox Flow Battery from Leachate of Industrial Waste

Fly ash, a typical waste driven out of boilers in combustion plants, contains a large range of metal oxides, and leads to environmental consequence without proper treatment. In this study, we focus on a fly ash generated from combustion of oil refinery waste, which includes substantial amount of metal oxides (mainly vanadium oxide and nickel oxide). Instead of landfill, chemical leaching was applied to extract and separate metallic components in the fly ash. Because of the high concentration of vanadium ion inside, the leachate can be used as the electrolyte in vanadium redox flow battery (VRFB). Unlike vanadium-related product synthesized from leachate, this application avoids solid-liquid separation and minimizes the wastewater generation. Meanwhile, as the secondary metallic composition, nickel ions become a low-cost resource for synthesis of nickel-dope nanomaterial that can be applied in VRFB as electrode materials to enhance V³⁺/V²⁺ and VO₂⁺/VO²⁺ reactions.