Abstract
The distribution coefficients of maltooligosaccharides with degrees of polymerization (d.p.) of 1 to 7 on cation-exchange resins (Amberlites HFS-471X and CG-60) with various divinylbenzene (DVB) contents and alkali-ion forms were determined by the moment analysis of elution curves of the saccharides. The distribution coefficients were largely dependent on both the DVB content and the ionic form, as well as on d.p. The resin with the higher DVB content gave the smaller coefficient. As the radius of the hydrated ion became larger, the distribution coefficient was reduced. The resin-phase diffusion and axial dispersion coefficients were also determined for maltooligosaccharides with d.p. of 1 to 3. Regardless of the DVB content and the ionic form, the resin-phase diffusion coefficient was correlated with the molecular diffusivity of each solute by a parallel pore model with a tortuosity factor of 4.0. The mixing lengths of flow for Amberlites HFS-471X and CG-60 were 1.9 and 1.5 times as long as their mean diameters, respectively. By using the parameters evaluated, the effects of some operating variables on the resolution of maltooligosaccharides with d.p. of i and i+1 (i=1 to 6) are discussed.
