“…23 CCRs have been used for extraction of zeolites, 2,24,25 mullite, 26 glass-like materials, 27 and composite materials such as plastic composites 28 and metal composites. 29 Several studies confirmed CCRs as potential adsorbents for removal of arsenic, boron, cadmium, chromium, fluoride, lead, mercury, nickel, pesticides, phosphate, zinc, color, and organic materials from waste water. 2,24 Golden and Wilder 30 proposed a conceptual commercialscale design to recover various raw materials such as alumina, ferric oxide, gypsum, and alkali sulfate salts from fly ash based on a direct acid leaching process.…”