A novel reactor design which simulates countercurrent reaction chromatography is described. Rapid separation of products from reactants allows high conversions in both equilibrium limited and low per pass conversion reactions. Two studies of solid catalyzed reactions are reviewed. Application of this technology to a mesitylene hydrogenation reaction shows an increase in conversion from 40% (at equilibrium, 473 K) to over 80%. A modified reactor configuration applied to the oxidative coupling of methane to ethane and ethylene shows a 12 fold increase in conversion for this low per pass conversion reaction, with yields twice that reported in conventional reactors.