A comprehensive review on Cd(II) removal from aqueous solution

Cadmium(II) is a highly toxic element and can cause a serious threat to living organisms. It is listed as an carcinogen by IARC and US EPA and stringent limits have been set for it in industrial wastewater (discharged into water bodies containing cadmium) as well as in drinking water. Therefore, an efficient and economic process to remove cadmium from aqueous solution is a pressing need. In this paper, all the available processes to remove cadmium from aqueous solution have been listed and the broad range of research work done by researchers in this field has been evaluated. The operational conditions of various processes have been briefly discussed. About 218 published studies are reviewed in this paper in order to provide insight into efficient and economic processes for the removal of cadmium. From the study, it is evident that adsorption, especially Biosorption, has been used by most of the researchers during the last few decades and it has proved to be a very efficient and economic process. But a lack of recent work has been observed in the area of precipitation and coagulation which could otherwise be an economic and convenient method.