Simulated moving-bed is used to overcome the difficulty of circulating and separating resins from the pulp in resin-in-pulp process. This makes the processes of adsorption of metals

regeneration and washing of resins to be finished in only one device. In order to provide a sound theoretical basis for the design of the new type contactor

the overall mass transfer coefficients are calculated and concentration curves of each stage in continuous operations are formulated. Experimental results show that the flow rate and ion concentration in the feed pulp have different effects on the concentration curves of a single stage or four-stage continuous operation. Experimental results fit well to the theoretical model. The concentration curves and overall mass transfer coefficients for a single stage and four-stage operation under different conditions are obtained.