[en] Experimental measurements have been made of the rates of sorption of uranyl sulphate from acidic sulphate solutions on to several anion exchange resins. Most of these measurements were made with Amberlite IRA 400, for which a resin phase uranyl sulphate self-diffusion coefficient of 1.66 x 10^-8 cm²/sec was found for an aqueous uranium concentration of 0.004M. Experiments on this resin indicated that solid phase diffusion controlled the sorption of uranium when the aqueous uranium concentration was between 0.0001 and 0.004M for agitated particles of 0.86 mm diameter. The solution conditions investigated were similar to those found in industrial leach liquors prior to uranium extraction. A computer programme was developed to simulate a multistage fluidised bed contactor. The mathematical model was written so that it could utilise a variety of equations describing sorption kinetics. It was satisfactorily compared against several sets of pilot plant data. Though solid phase diffusion appeared to control in the range of aqueous uranium concentrations 0.0001M to 0.004M, the rate constant in the Fickian diffusion model was found to be a function of aqueous uranyl sulphate concentration. (author)