Duarte, GrazieleTeixeira, Mônica CristinaOlusegun, Sunday J.Ciminelli, Virgínia Sampaio Teixeira2022-11-042022-11-042021DUARTE, G. et al. Mechanisms of arsenic removal from simulated surface water based on As (III) retention on thiol chelating resins. Environmental Nanotechnology, Monitoring & Management, v. 16, 2021. Disponível em: <https://www.sciencedirect.com/science/article/pii/S2215153221001070>. Acesso em: 11 out. 2022.2215-1532http://www.repositorio.ufop.br/jspui/handle/123456789/15759A novel system for arsenic speciation in the aqueous environment has been developed based on the high affinity of As(III) for the sulfhydryl groups present in thiol resins (R-S). The performance of tailor-made cartridges filled with the thiol resin was then compared with a commercial silica-based anion exchange cartridge with a qua- ternary ammonium group (R-N) typically used for As(V) speciation. Both were able to separate arsenic species efficiently, As(V) and As(III), within a broad pH range using flow rates of up to 5 ml min− 1 . The R-S resin was shown to be suitable for the inorganic arsenic speciation in aqueous systems containing calcium, magnesium, ferrous and ferric ions. The R-S selectivity for As(III) was affected only at sulfate or phosphate/As mass ratio > 500, in a behavior similar to R-N for As(V). The thiol resin’s selectivity for As(III) and its immobilization mechanism were investigated through X-ray Absorption Spectroscopy. At pH 5, each arsenic atom bounds to three sulfur atoms, with an As-S inter-atomic distance of 2.26 ± 0.01 Å, and a coordination number (CN) of 2.8 ± 0.3. The separation of the neutral As(III) species by a thiol resin presents itself as an alternative to the available anion exchange methods. The sorption of As(III) on the thiol resin followed a pseudo-second-order kinetic model and can be described by the Langmuir isotherm.en-USrestritoArsenic speciationAdsorption mechanismIon exchangeSulfhydrylX-ray absorption spectroscopyArtigo publicado em periodicohttps://www.sciencedirect.com/science/article/pii/S2215153221001070https://doi.org/10.1016/j.enmm.2021.100532