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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. [ABSTRACT FROM AUTHOR]

Water contaminated with monoaromatic hydrocarbons must be treated before being discharged due to the high toxicity of these compounds. Various treatment methods are currently used, among them processes that involve adsorption. Polymeric resins has been used to treat water and then it is a promising method to be applied for removing various compounds from oily water. In this work, two polymeric resins (divinylbenzene − DVB and methylmethacrylate‐divinylbenzene − MMA‐DVB), previously synthesized, were evaluated for removal of toluene from water. Batch tests were performed to study the adsorption equilibrium using the Langmuir and Freundlich models, while the adsorption kinetics were analyzed by the pseudo first‐order and pseudo second‐order models. Besides this, the saturation and regeneration were analyzed with continuous flow tests. The empirical model of Freundlich described the adsorption equilibrium data better than the theoretical model of Langmuir. Likewise, the pseudo first‐order model best represented the experimental data regarding the adsorption kinetics of the systems studied. In the batch tests, the resin DVB was most efficient in removing toluene, but it reached equilibrium with a longer contact time. The continuous flow tests showed that the two systems presented good removal performance; however, DVB column could treat ≈600 bed volumes of water while MMA‐DVB treated only ≈280. The absorbents revealed great potential to be regenerated. [ABSTRACT FROM AUTHOR]

The aim of this paper was to compare two kinds of adsorbents (walnut shell and polymeric resins) in terms of their efficiency to remove oil from water, since walnut shell losses weight during the process requiring interruption, while polymeric resins do not. Polymeric resins based on glycidyl methacrylate and divinylbenzene (GMA-DVB) and styrene and divinylbenzene (STY-DVB) were synthesized and characterized. All adsorbents were tested by continuous flow process, eluting 3,000 bed volumes of synthetic oily water, and the oil content was monitored by fluorescence spectroscopy. Although the walnut shell presented high efficiency (~94%), STY-DVB was even better (~100%) besides presenting better mechanical resistance. Moreover, polymeric resins, mainly when based on GMA, can be chemically modified to remove specific contaminants still remaining in water after conventional treatment. [ABSTRACT FROM AUTHOR]