An effective adsorbent developed from municipal solid waste and coal co-combustion ash for As(V) removal from aqueous solution

A new adsorbent was developed from waste ash resulting from municipal solid waste and coal co-combustion power plant. The ash was firstly subjected to hydrothermal treatment for zeolite synthesis, and then modified with iron(II) ions by agitation (ISZ) or ultrasonic (UISZ) treatment. The effect of operating factors such as pH, contact time, initial As(V) concentration and adsorbent dosage was investigated and the optimum operating conditions were established. The adsorption capacity for As(V) onto UISZ and ISZ were 13.04 and 5.37 mg g−1, respectively. The adsorption isotherm data could be well described by Langmuir isotherm model. The optimum initial pH values for As(V) removal were 2.5 and 2.5-10.0 by ISZ and UISZ, respectively. The results indicated that ultrasound treatment scattered the particles of the adsorbent uniformly, which was in favor of impregnating iron ions into pores. Leaching of hazardous elements from the used adsorbents was very low. Accordingly, it is believed that the adsorbents developed in this study are environmentally acceptable and industrially applicable for utilization in arsenic-containing wastewater treatment.