Advanced approaches for heavy metals removal from industrial wastewater

Abstract

Abstract Industrial wastewater containing organic and inorganic pollutants has been of major concern because its high toxicity poses a major threat to health and the environment. The discharge of large amounts of heavy-metal-contaminated wastewater, including Pb, Cr, Cd, Cu, Ni, As, and Zn, is the most hazardous among the chemical-intensive industries. Heavy metals are so toxic that even trace amounts can cause grave danger. Owing to their high solubility in the aquatic environments, heavy metals can be absorbed by aquatic organisms; once they enter the food chain, large concentrations of heavy metals tend to accumulate in the human body and other organisms. These pollutants require high-priority advanced remediation technologies for complete removal, as many conventional technologies transfer the pollutant from one phase to another instead of complete removal. During the past decades, physical, chemical, and biological remediation technologies were used for the removal of heavy metals from industrial wastewater, including the use of efficient low-cost adsorbents such as fly ash, peat moss, activated carbon, bioremediation, red mud, and biomass. This chapter focuses on the recent trends and advanced heavy metal remediation technologies such as adsorption using novel adsorbents, nanoadsorbents, multifunctional nanomaterials, polymeric nanocomposites, zeolites, clays, hydrogels, ion exchange resins, membrane filtration (advanced polymeric membranes, nanofiltration, and reverse osmosis), electrodialysis, and photocatalysis. Treatment of heavy metals using advanced remediation technologies is driven by many factors such as reduction of cost, less time, high reactivity, high specificity, and ease. The advantages and disadvantages of the application will also be included.