An electrochemically modified novel tablet porous material developed as adsorbent for phosphate removal from aqueous solution

In the present study, a novel tablet porous material (TPM) was developed from Kanuma clay (K-clay), corn starch, iron powder, white cement and calcium oxide. It was prepared through an electrochemical surface modification (ESM) method. Laboratory-scale batch experiments were conducted to evaluate the phosphate adsorption capacity of TPM and ESM modified TPM (ECTPM) from aqueous solution. The adsorption isotherms, adsorption kinetics and major factors such as temperature and pH 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 3.61 mg g−1 onto TPM and 5.36 mg g−1 onto ECTPM, respectively, and equilibrium could be attained in 2 h. The solution pH had little effect on TPM phosphate removal when pH varied from 5.0 to 9.0. ECTPM and TPM are of high selectivity on phosphate adsorption. This novel developed TPM is a more promising adsorbent than other clay mineral materials for phosphate removal from wastewater.

► A low cost novel tablet porous material (TPM) was developed for phosphate removal. ► TPM was modified by an electrochemical surface modification process (ECTPM). ► The adsorption capacity of ECTPM (5.36 mg g−1) was higher than TPM (3.61 mg g−1). ► TPM and ECTPM were of high selectivity on phosphate adsorption.