The problem of gas absorption followed by instantaneous irreversible chemical reaction in a slurry containing sparingly soluble fine reactant particles is considered. Models are developed for an infinitely deep quiescent liquid and, using the film theory, for an agitated liquid when the reactant particle dissolution in the liquid film next to the gas-liquid interface is nonnegligible. Simple analytical expressions for the rate of gas absorption are derived under the assumption of slow particle dissolution, and conditions are given for applicability of the models. A numerical example for the system SO2-Ca(OH)(2) in water is discussed.