A review on the industrial waste based adsorbents for the removal of pollutants from water: Modification methods and adsorption study

Human activities have discharged large quantities of pollutants into the water body. Industrial wastes have demonstrated potential for water remediation, and further modifications can enhance their sorption capacities for pollutants. Over the past few decades, various modification techniques have been conducted to improve the sorption performance of industrial wastes and achieved encouraging results. However, the limited availability of relevant summaries hinders our ability to gain a deeper and more detailed understanding of the advantages of modification methods, restricting the advancement of industrial wastes modification. Therefore, an extensive list of various modification techniques for industrial waste materials were compiled and their adsorption capacities under optimal conditions for the removal of pollutants were presented in this review. Modification categories and their effects on the adsorption mechanism were introduced in detail along with discussing the key advancement on the preparation of adsorbents. Furthermore, knowledge gaps, uncertainties, and future challenges involved in the fabrication of modified industrial wastes based adsorbents are also identified. This review provides an important insight on using industrial waste materials for preparing adsorbents in water remediation, which will give quite valuable information for developing industrial waste based adsorbents.