A novel tablet porous material developed as adsorbent for phosphate removal and recycling

In the present study, a novel tablet porous material (TPM) was developed from Kanuma clay (K-clay), corn starch, and calcium oxide. Laboratory-scale batch experiments were conducted to evaluate the phosphate adsorption capacity of TPM from aqueous solution. The adsorption isotherms, adsorption kinetics, phosphate recycling, and major factors such as temperature, pH, and dosage were investigated. The phosphate adsorption results fitted the Freundlich isotherm model very well, and the adsorption process was an endothermic and spontaneous reaction which could be described by a pseudo second-order kinetic model. The maximum phosphate adsorption capacity was 4.39 mg g(-1), and its equilibrium could be attained in 2h. The solution pH had little effect on TPM phosphate removal when pH varied from 5.0 to 9.0. 70.29% of adsorbed phosphate could be recycled when 0.2N HCl was used as eluant, and the present developed TPM could be recovered and reused for 5 times. This novel developed TPM is a promising adsorbent than other clay mineral materials for phosphate removal from wastewater.