Reactor design for fluid-solid, noncatalytic reaction depends on the prediction of the performance of the reactor kinetically. Most mathematical models used to handle a fixed bed reactor in which the solid bed constitutes one of the reactants, while a second reactant is in the fluid phase, are complex and difficult to handle. A new mathematical model which is easier to handle has been developed to describe the system under investigation. The model was examined theoretically and experimentally. A column packed with a chelating cloth filter to separate radionuclides from radioactive waste solution is used as a practical application for the model. A comparison of the model predictions with the experimental results gives a satisfactory agreement at most of the process stages.