A review on the efficacy of the application of myriad carbonaceous materials for the removal of toxic trace elements in the environment

The literature on adsorption of heavy metals such thallium (Tl), tellurium (Te), mercury (Hg), cadmium (Cd) and lead (Pb) using carbon based adsorbents such as activated carbon (AC), carbon nanotubes (CNTs), carbon nanofibers (CNFs) and carbon composites has been reviewed. The adsorption capacities for the above mentioned by AC, CNFs, CNTs and carbon composites operated under different conditions are summarized in and where possible, they are compared. In addition, parameters that play a role in assessing the performance of adsorbents including surface area, removal efficiency, precursors used to produce carbon and the isotherm models used to further study their adsorptive capability, are provided. In this review valuable information has been provided on efforts made by other researchers on the removal of heavy metals and the modification of carbon based adsorbents for effective removal of heavy metals. Furthermore, due to the effectiveness of some adsorbents, a recommendation for the up-scaling of production carbon adsorbents for the removal of heavy metals especially in wastewater treatment plants has been made.