Adsorbent prepared from red mud and its adsorption characteristics of As(Ⅴ)

摘要

A novel method to prepare an activated red mud (activated RM) adsorbent was developed that was mainly produced from RM. The batch adsorption experiments were conducted for the study of the adsorptive performance by activated RM adsorbent. Adsorption of As(Ⅴ) on activated RM was studied as a function of dosage and time. Results from the batch experiments, conducted at an initial concentration of 0.2 mg/L of As(Ⅴ), suggest that arsenate removal efficiency was up to 95%. Langmuir and Freundlich isotherms equation were used to fit the adsorption isotherms. Adsorption capacity of activated RM was found to be 127.0, 111.9 and 46.7 mg/g at pH 6, 7, 9, respectively. The results indicate that there is no significant change in the equilibrium concentration after 12 h. The adsorption kinetic curve for the As(Ⅴ) fit well with the pseudo-second-order equation. The leaching liquid by activated RM after the toxicity characteristic leaching procedure test can reach the Drinking water standards of China (GB 5749-2006). The adsorbent is a safe application.