A comprehensive review on conventional and biological-driven heavy metals removal from industrial wastewater

Due to high concentrations of numerous harmful and hazardous pollutants, particularly heavy metals, industrial wastewater has become a major problem. Heavy metal pollution and its implications for human health and the environment have increased research in developing low cost and sustainable remediation technology. Diverse conventional physicochemical and green biological methods are applied to remove heavy metals (HMs). This review article covers both the conventional and biotechnological approaches used for removal of HMs from wastewater and evaluate them based on their efficiency. Adsorption, coagulation, flocculation, chemical precipitation, membrane separation, ion exchange, flotation, and electrochemical technologies are examples of conventional methods. In some circumstances, these procedures produce quick results, although they are less efficient and cost more than biotechnological heavy metals removal (HMR). The current state and prospects of biosorption and bioaccumulation for environmental bioremediation are reviewed. Environmental considerations are evaluated, with a focus on the removal efficiency of biosorption and bioaccumulation. HMR efficiency and cost effectiveness of a range of biosorbents for the removal of pollutants are described. Furthermore, the equilibrium, kinetic, and thermodynamic behavior of the heavy metal biosorption process, based on kinetic and isotherm models, are presented. Overall, this study provides clear information of biological processes, which will help surmount technological limitations of bioseparation process application.