An experimental and mathematical modeling study of a simulated countercurrent moving bed chromatographic reactor for oxidative coupling of methane to ethane and ethylene is reported. The experiments were done in a laboratory-scale three-section simulated moving bed reactor. Operating conditions were deduced from independent experiments in a microcatalytic fixed-bed reactor and from adsorber dynamics studies. With a YBa2Zr3O9.5 catalyst and activated charcoal adsorbent, the sum of the ethane and ethylene yields at optimum simulated moving bed operating conditions was 45%. Numerical simulations of the reactor performance were done and compared with experimental results.