Water purification by adsorption of pigments or pollutants via metaloxide

The growth in industrialization ultimately enhances the toxic discharges of wastewater containing hazardous dyes from various industrial units as a consequence severe ecological and public health issue exhibit a major challenge to conventional system to decontaminate water. Depending upon experimental constrains various physicochemical and biological treatment process have been made possible to remove pollutant of interest according to their functional abilities. In spite of all the treatment techniques, Adsorption process is considered one of the most excellent option due to the cost-effectiveness, ease of operation, high removal efficiency and regeneration of adsorbents. Over the decades, metal oxides and their composites-based absorbents showed tremendous efficiency in wastewater decontamination by dyes. The ample surface-active sites, tunable surface chemistry, ease to synthesize and functionalization, high accessible surface area, economic viability, and good recyclability make the metal oxide-based nanomaterials potential adsorbents for fast and effective removal of a wide range of heavy metal and metalloid ions. The presence of toxic dye molecules in water system poses a serious threat to aquatic ecosystem. This paper comprehensively reviews the source of contamination, possible health hazards, and adsorption technique by metal oxides to eliminate dyes from wastewater. Also, an environmentally friendly and self-sustainable treatment method should be explored to address this problem for emerging contaminants.