A method of treating a collection of resin beads (a) comprising the steps of (a) providing the collection of resin beads (a), wherein the resin beads (a) comprise one or more vinyl polymers having quaternary ammonium groups, wherein the amount of vinyl polymer in the resin beads (a) is 50% or more, by weight based on the weight of the resin beads, and wherein the one or more vinyl polymers are selected from vinyl aromatic polymers and acrylic polymers; wherein 90 mole % or more of the quaternary ammonium groups are each associated with a chloride anion; (b) bringing the collection of resin beads (a) into contact with an aqueous solution (b) comprising one or more dissolved n X q to form a mixture (b), wherein M is a cation of charge (+i) that contains no metal atom, alkali metal atom, or alkaline earth atom; wherein X is an anion of charge (-j), wherein X is selected from the group consisting of carbonate, bicarbonate, dihydrogen phosphate, formate, acetate, and aminoacetate; and wherein (n•i) = (q•j); (c) separating water and compounds dissolved in the water from the mixture (b), to form resin beads (c) and waste solution (bw); (d) bringing resin beads (c) into contact with an aqueous solution (c) comprising dissolved p, to form a mixture (d) wherein M3 is a cation of charge (+k) that contains no metal atom, alkali metal atom, or alkaline earth atom; and wherein p = k; and wherein, at any point in the method, the collection of resin beads is optionally washed by being brought into contact with water and then separated from the water. (a) providing the collection of resin beads (a), wherein the resin beads (a) comprise one or more vinyl polymers having quaternary ammonium groups, wherein the amount of vinyl polymer in the resin beads (a) is 50% or more, by weight based on the weight of the resin beads, and wherein the one or more vinyl polymers are selected from vinyl aromatic polymers and acrylic polymers; wherein 90 mole % or more of the quaternary ammonium groups are each associated with a chloride anion; wherein the resin beads (a) comprise one or more vinyl polymers having quaternary ammonium groups, wherein the amount of vinyl polymer in the resin beads (a) is 50% or more, by weight based on the weight of the resin beads, and wherein the one or more vinyl polymers are selected from vinyl aromatic polymers and acrylic polymers; wherein 90 mole % or more of the quaternary ammonium groups are each associated with a chloride anion; (b) bringing the collection of resin beads (a) into contact with an aqueous solution (b) comprising one or more dissolved n X q to form a mixture (b), wherein M is a cation of charge (+i) that contains no metal atom, alkali metal atom, or alkaline earth atom; wherein X is an anion of charge (-j), wherein X is selected from the group consisting of carbonate, bicarbonate, dihydrogen phosphate, formate, acetate, and aminoacetate; and wherein (n•i) = (q•j); wherein M is a cation of charge (+i) that contains no metal atom, alkali metal atom, or alkaline earth atom; wherein X is an anion of charge (-j), wherein X is selected from the group consisting of carbonate, bicarbonate, dihydrogen phosphate, formate, acetate, and aminoacetate; and wherein (n•i) = (q•j); (c) separating water and compounds dissolved in the water from the mixture (b), to form resin beads (c) and waste solution (bw); (d) bringing resin beads (c) into contact with an aqueous solution (c) comprising dissolved p, to form a mixture (d) wherein M3 is a cation of charge (+k) that contains no metal atom, alkali metal atom, or alkaline earth atom; and wherein p = k; wherein M3 is a cation of charge (+k) that contains no metal atom, alkali metal atom, or alkaline earth atom; and wherein p = k;