title: Alkaline earth metal cation exchange: effect of mobile counterion and dissolved organic matter.
abstract: The goal of this research was to provide an improved understanding of the interactions between alkaline earth metals and DOM under conditions that are encountered during drinking water treatment with particular focus on cation exchange. Both magnetically enhanced and nonmagnetic cation exchange resins were converted to Na, Mg, Ca, Sr, and Ba mobile counterion forms as a novel approach to investigate the exchange behavior between the cations and the interactions between the cations and DOM. The results show that cation exchange is a robust process for removal of Ca(2+) and Mg(2+) considering competition with cations on the resin surface and presence of DOM. DOM was actively involved during the cation exchange process through complexation, adsorption, and coprecipitation reactions. In addition to advancing the understanding of ion exchange processes for water treatment, the results of this work are applicable to membrane pretreatment to minimize fouling, treatment of membrane concentrate, and precipitative softening.
authors.affiliation: Department of Environmental Engineering Sciences, University of Florida, PO Box 116450, Gainesville, Florida 32611-6450, United States.
authors.forename: Katrina
authors.initials: K
authors.lastname: Indarawis
authors.forename: Treavor H
authors.initials: TH
authors.lastname: Boyer
mesh_terms: D002411:Cation Exchange Resins / Q000737:chemistry*; D011232:Chemical Precipitation; D060766:Drinking Water; D060587:Groundwater; D006812:Humic Substances; D007474:Ion Exchange; D008673:Metals, Alkaline Earth / Q000737:chemistry*; D018508:Water Purification
chemical_list: D002411:Cation Exchange Resins; D060766:Drinking Water; D006812:Humic Substances; D008673:Metals, Alkaline Earth