Assessment of cadmium ion adsorption capacity in water by biochar produced from pyrolysis of cow dung

Biochar production from cattle waste and the potential of biochar as an adsorbent for treating pollution are among the hot research topics in recent years. The goal of this study is to evaluate the ability to adsorption Cd2+ from water of biochar produced from cow dung at varying pyrolysis temperatures (300, 450, and 500oC).The study determineda number of surface-level chemical characteristics of the biocharsamples such astotal organic carbon (TOC), pH, pHpzc, functional group H+ , OH- , and cation exchange capacity (CEC). Biochar samples were subjected to two different experiments: the first submerged the biochar in Cd2+ solutions at different concentration (0- 132 mgCd2+ .L -1 ) for a fixed 12 h and the second submerged the biochar in Cd2+ solutions at a fixed concentration of 66 mgCd2+ .L -1 for a varying length of time. Adsorption kinetics and equilibrium analyses were conducted on the samples at the end of the experiments. The Cd2+ adsorption process of these biochar forms fit Langmuir and Freundlich adsorption models as well as a pseudo-second-order kinetic model. The study concluded that biochar produced from pyrolysis of cow dung could be employed as an adsorbentfor the removal of Cd2+ from water.