Reactions involved in photocatalytic hydrogen production through water splitting combined with a hole scavenger involve several stages that make kinetic analysis quite complicated. In the present work, a kinetic model for the photocatalytic production of hydrogen has been developed based on competitive adsorption, considering the photocatalytic decomposition of an organic molecule coupled to hydrolysis through photocatalytic water splitting. Parameter estimation is performed by using the Levenberg-Marquardt method. Model validation results give an estimation of the strength of adsorption of acetol and the acetaldehyde.