Removing ammonium from water using porous resins: influence of polymer structure, ion exchange capacity and porosity

This study describes the synthesis of polymeric resins based on styrene (STY), glycidyl methacrylate (GMA) and divinylbenzene (DVB), modified chemically through sulfonation reactions during different time intervals, to learn the influence of the materials’ structure on their adsorption capacity and evaluate their potential for application in the removal of ammonium from wastewater to levels compliant with the technical standard NT202, R-10 (INEA, 1986). The results showed that besides the duration of the sulfonation reaction, factors such as surface area and pore diameter also contributed significantly to the ammonium absorption process. The efficiency of the formulations was in decreasing order DVB(7:3)(2)S, DVB(7:3)(24)S, STY-DVB(7:3)(2)S and GMA-DVB(7:3)(2)S. Of these, DVB(7:3)(2)S had the greatest surface area but had low ion exchange capacity. The resin with the greatest exchange capacity was STY-DVB(7:3)(2)S, but it had efficiency about 20% lower than the former resin, showing a result very near that of GMA-DVB(7:3)(2)S.