Evaluation of Crosslinked Sulfonated Polymers Derived from Different Resins for Removal of Ammonium Ions

Abstract

AbstractAmmoniacal nitrogen is an environmental pollutant present in various effluents, such as landfill leachate. It is possible to use ion‐exchange resins in systems for tertiary treatment of effluents containing NH4+ ions and as support for NH3 recovery after treatment of these effluents by employing air stripping. This article presents an exploratory study of sorption of NH4+ ions by sulfonic resins prepared from styrene‐divinylbenzene (Sty‐DVB) copolymers with varied morphological structures: hypercrosslinked resin, a macroporous copolymer prepared by conventional aqueous suspension polymerization, and a polyHIPE copolymer. These three resins are sulfonated by employing concentrated sulfuric acid. The sulfonic resin derived from hypercrosslinked resin has the highest cation exchange capacity (5.06 meq g−1) and is selected for batch studies and column tests. The best result (removal rate of 87%) is achieved with 20 g of resin, time of 20 min, and concentration of 100 ppm. Kinetic behavior and sorption processes are best described by the pseudo‐second‐order, Weber–Morris intraparticle diffusion, and Langmuir models. The saturation point occurs when 900 mL of the NH4+ solution at 2500 ppm (15 mL min−1) is percolated through the column. The working capacity of this resin is 14.06 g cm−3. The resin can be reused during five cycles with removal efficiency between 71% and 82%.