Systems and methods are provided for enhancement of gaseous CLC in a fixed-bed process, marked by an increase in CO2 capture efficiency and oxygen carrier utilization, while reducing disadvantages of a conventional fixed-bed operation. The disclosed systems/methods provide a CLC fixed-bed reactor design in which the direction of the fuel gas is intermittently reversed during a single fuel oxidation step. In this reverse-flow mode, oxygen carrier reduction reactions are displaced over the ends of the reactor, which increases contact between fuel and oxidized solids and alleviates and/or mitigates problems of carbon deposition encountered by most oxygen carriers.