The use of outer-sphere complex formation reactions in ion-exchange chromatography Separation of oxalate and sulphate ions.
It has been found that outer-sphere complex formation reactions can be used to increase the selectivity of ion-exchange separations. A method has been developed for the quantitative separation of sulphate and oxalate. The stability constants of the sulphate and oxalate complexes of tris(ethylenediamine) cobalt(III) and hexa-amminecobalt(III) have been determined at different ionic strengths from the elution volumes and the parameters of the ion-exchanger bed, and the values at I = 0 have been obtained by extrapolation. They are log K[Co(en)(+3)(3) + SO(2-)(4)] = 3.38; log K[Co(NH(3))(3+)(6) + SO(2-)(4) = 3.60; log K[Co(en)(3+)(3) + C(2)O(2-)(4) = 3.23.
Halmos
P
P
Institute for Analytical Chemistry, University of Chemical Engineering, Veszprém, Hungary.
Inczédy
J
J