Low-Cost Adsorbents and Nanomaterials for Removal of Heavy Metals from Contaminated Water: Review

Abstract

Worldwide concern has been raised about the contamination of heavy metals and their harmful impacts on both environment and human health. Numerous technologies have been changing throughout time to address this issue. Among the most practical and economical techniques, adsorption is still used to cleanse wastewater that is contaminated with heavy metals. Silica, zeolites, clay, and activated carbon are a few adsorbents that have been thoroughly explored in the past. From a review of the literature, numerous adsorbents' adsorption abilities were evaluated, in addition to the capability of other metals to absorb substances. Adsorbents can also be modified to increase their adsorption capability. Although the expense of regeneration is significant, there are numerous commercial, industrial, and environmental advantages to reducing the use of fresh adsorbent. This review makes an effort to give a thorough overview of various modified adsorbents, their efficiency, and nanotechnology-based strategies in eliminating contaminants from wastewater that have been studied in the last ten years. Additionally, it is implied that nanomaterials, nanocomposites, and nanofiltration have demonstrated remarkable attention for the reduction of these heavy metals.