Periodic monitoring of nano clay as the potential adsorbent to remove metal and dyes from wastewater: A review

Abstract

There has been an increase in heavy metals and dyes contamination in the wastewater, and conventional treatment plants are not designed for such contaminants. Therefore, the heavy metals and dyes must be removed from wastewater for sustainable wastewater treatment. In recent decades adsorption is one of the most studied and applied techniques for heavy metals and dye removal from wastewater to be used as a useful treatment method. Nano-clay has been observed for its unique characteristics and properties as an adsorbent in many adsorption processes for the last few years. The scope of the current review work is removing dye and heavy metals using Nano clay with special context to the effect of pH and temperature. Due to its high specific surface area (>800 m2/g), high cation exchange capacity (>120 cmol kg⁻¹), low cost, and ability to be synthesised, Nano clay (NC) is known as an efficient adsorbent. To enhance the removal efficiency of NC, several studies reported the modifications of Nano-clay using different chemicals and polymers. Based on findings from the current analysis, it has been noted that Nano-Clay has promise as an adsorbent for almost all types of heavy metals and dyes. The review synthesis showed that the maximum removal varies from 31.5 to 2435.7 mg/g for Congo Red dyes and 9.02 to 100.09 mg/g (lead) for heavy metals by using Nano-clay. In this work, we have tried to summarize the advancement done in the adsorption technique to remove heavy metals and dyes using NC.