Electrokinetic remediation of heavy metals from municipal solid waste incineration fly ash pretreated by nitric acid

Municipal Solid Waste Incineration (MSWI) fly ash has high concentration of Heavy Metals (HMs) which are hazardous to environment. Moreover, it has high pH and buffering capacity which hinders the removal of HMs. Another constraining factor is considerable fraction of HMs which existe in oxidizable and reducible states. The acid pretreatment of MSWI fly ash is key solution to these problem. Therefore, current experiment is carried out to evaluate the effect of acid pretreatment of MSWI fly ash and reaction/proposed time on removal efficiency of HMS through electrokinetic experiment. The leaching experiment results show that acid pretreatment has increased the desorption/release of heavy metals ions (Pb2+, Cd2+, Cu2+ and Zn2+). It enhances the migration of HMs ions in electrolytic cell which get precipitated at cathode thereby increasing the removal efficiency of HMS in electrokintic experiment. Moreover, it is found that prolonged proposed time (12 d) has significant effect on removal e...