This invention is a process for the chromatographic separation of a fluid mixture in which the mixture is contacted with an ion-exchange resin, eluted through the resin under conditions such that the rate of passage of one component of the mixture through the resin bed is retarded relative to the rate of passage of a second component of the mixture, and a first product stream rich in said first component and a second product stream rich in said second component are recovered. The invention involves the use of an ion-exchange resin made from a copolymer which is prepared in a multi-stage polymerization process. The use of this resin is found to provide fast separation kinetics and increases the overall speed and efficiency of the separation. This invention is particularly suited for fructose/glucose separations in the preparation of high fructose corn syrup.