Study on the regulation mechanism of cadmium adsorption system mediated by extraneous dissolved organic matter

Abstract Adsorption of biochar on heavy metals is one of the hot spots in the application of biochar. However, the mediation of existing extraneous substances in the environment, such as dissolved organic matter (DOM), could regulate and affect the heavy metals adsorption process on biochar. In our study, we mainly focus on the regulation mechanism of modified biochar on the adsorption process of cadmium mediated by exogenous DOM. The modification significantly changed the functional groups composition on biochar, thus improving the adsorption capacity of cadmium on biochar. In the adsorption system concerned, the combination was formed between DOM and cadmium to a certain extent. The combination had a certain correlation with the influence on the adsorption capacity of cadmium onto biochar in the system.