1. Kanawade, S.M., Gaikwad, R.W.: Adsorption of heavy metals by activated carbon synthesized from solid wastes. Int. J. Chemical Eng. Appl. 2(3), 207 (2011)
2. Naja, G.M., Volesky, B.: Toxicity and sources of Pb, Cd, Hg, Cr, As, and radionuclides in the environment. Heavy Metals Envir. 8, 16–18 (2009)
3. Harun, N.Y., Han, T.J., Vijayakumar, T., Saeed, A., Afzal, M.T.: Ash deposition characteristics of ındustrial biomass waste and agricultural residues. Mater. Today: Proc. 19, 1712–1721 (2019)
4. Simeng, L., Chen, G.: Using hydrogel-biochar composites for enhanced cadmium removal from aqueous media. Mater.Sci. Eng. 2(6), 294–298 (2018)
5. Bogusz, A., Oleszczuk, P.: Effect of biochar addition to sewage sludge on cadmium, copper and lead speciation in sewage sludge-amended soil. Chemosphere 239, 124719 (2020)