We discuss application of the continuous-time random walk (CTRW) model to studying the kinetics of pseudo-first-order reactions in zeolites. The model includes distance-dependent reaction mechanism, details of the zeolite structure, and dynamics of migration of guest molecules between adsorption sites. Diffuse-reflectance transient-absorption study of triplet anthracene quenching by azulene in NaY zeolite shows that quenching can occur when reactants are located not only in the same supercage but also in the neighboring supercages. Markovian CTRW model with nearest-neighbor interactions on a diamond lattice explains the experimental decay data. ©2000 American Institute of Physics.