Zero-valent iron and its derivative composites for heavy metal adsorption

Heavy metals are regarded priority pollutants jeopardizing the ecosystem's security, including water, the lifeblood of the universe, due to human activities. Interestingly, part of the continuous concerted efforts by the research community is the application of zero-valent-based sorbents (ZVBS). Thus, this book chapter mainly focuses on the usage of zero-valent iron and its derivative composite materials for the aqueous phase sequestration of toxic metals. The performance of ZVBS was critically and comprehensively analyzed with respect to adsorption capacity for various hazardous heavy metals. The adsorption equilibrium isotherm, kinetic modeling, and thermodynamic nature of the adsorption operation were concisely discussed to elucidate the mechanism of adsorption and process optimization. The regenerability, recyclability, and stability of ZVBS were also evaluated to shed light on its potential eco-economic benefits. In addition, the competitivity adsorption study was pragmatically presented in terms of the effect of background ions/electrolytes to assess the holistic applicability of ZVBS in real-life scenarios. In the end, knowledge gaps, prospects, and interesting areas for future research were presented.