Active microchannel heat exchanger

The present invention relates to an active microchannel heat exchanger, comprising a plurality of assemblies comprising microchannels, each of said plurality of assemblies comprising an exothermic reaction chamber, an exhaust chamber, and a heat exchanger chamber and a plurality of valves that permit taking at least one of said plurality of assemblies off line for clean up or regeneration while the remaining assemblies or units continue operation.