Amino-functionalized porous PDVB with high adsorption and regeneration performance for fluoride removal from water

Excessive fluoride anions in drinking water are toxic to the health of human beings. In this article, an effective fluoride removal adsorbent on the basis of amino-functionalized porous polydivinylbenzene (PDVB) was prepared through low cost processes, which included solvothermal preparation of porous PDVB and subsequent surface amino-functionalization. The obtained amino-functionalized porous PDVB (A-PDVB) has high surface area of 443 m2 g-1 and high adsorption capacity towards fluoride anion up to 105.9 mg g-1. Considering adsorbents surface area, the adsorption capacity per unit surface area of A-PDVB is 0.24 mg m-2 which is more than 4 times of porous PDVB (0.058 mg m-2). The enhanced adsorption performance of A-PDVB was due to amino groups electrostatic interaction coupled with hydrogen bond binding with fluoride anions. In addition, the aminofunctionalized porous PDVB could be regenerated in high efficiency under alkaline conditions. This work not only exhibits the possibility of A-PDVB for application as an environment-friendly adsorbent for fluoride removal but also gives an insight into understanding mechanism of the fluoride anions adsorption onto aminofunctionalized porous PDVB.