Preparation and characterization of Fe-MSB and Al-MSB by efficient microwave irradiation

The ferric sulfate modified sodium bentonite(Fe-MSB) and the aluminum sulfate modified sodium bentonite (Al-MSB) were prepared with sodium bentonite(SB) which respectively were modified with ferric sulfate and aluminum sulfate as modifier by efficient microwave irradiation. The optimal preparation conditions were explored with the removal efficiency of phosphorus in simulated phosphorus wastewater using Fe-MSB and Al-MSB to adsorb as verifying the results by single factor experiment. Modification mechanisms and adsorption properties were analyzed by XRD, IR, SEM and specific surface area characterizations of Fe-MSB, Al-MSB and SB. The results showed that the optimum preparation conditions of Fe-MSB were ferric sulfate dosage of 0.08 g/g, microwave power of low fire and microwave time of 6 min. Under the condition, the removal rate and residual concentration of phosphorus were 99.92% and 0.02 mg/L, respectively. The optimum preparation conditions of Al-MSB were ferric sulfate dosage of 0.10 g/g, microwave power of medium low fire and microwave time of 7 min. Under the condition, the removal rate and residual concentration of phosphorus were 98.82% and 0.30 mg/L, respectively. The pore space, the layer spacing and specific surface area of Fe-MSB and Al-MSB increased significantly, and the adsorption performance of Fe-MSB and Al-MSB increased obviously. Moreover, the adsorption capacity of Fe-MSB was better than Al-MSB.