Patent ID: 8753590

Claim:
A method for separating a polyvalent metal species from one or more accompanying impurities, comprising: (i) contacting the polyvalent metal species and accompanying impurities with a composition comprising MnO 2 and a compound of formula (I): wherein: R is a polymer; each Y is independently a hydrogen or a negative charge; Z is either hydrogen or is not present; each n is independently 1, 2, 3, 4, 5 or 6; and wherein at least 50% of the surface of the compound of formula (I) is coated with MnO 2 so that the polyvalent metal binds to MnO 2 ; (ii) dissolving the MnO 2 bound to the polyvalent metal to form a solution; and (iii) contacting the solution with a complexing agent, so that the polyvalent metal binds to the compound of formula (I).