NOVELTY - A hydrogen reforming system comprises a cyclical compression chamber having an operational cycle with an internal pressure and temperature absent combustion effective for reforming the hydrogen-containing gas; a heating system for heating the hydrogen-containing gas to a non-combustible temperature; and a drive system for cycling the cyclical compression chamber.    USE - For producing hydrogen gas by reforming hydrogen-containing gas (claimed), e.g. methane.    ADVANTAGE - The novel system effectively reforms hydrogen-containing gas into hydrogen gas. It provides a non-combustion process for producing pure hydrogen; an integral arrangement of a cyclical combustion engine and a cyclical hydrogen reformation system; effective use of a piston and cylinder arrangement for simplified hydrogen production; internal or external heating of the reforming fuel; alternative methods of powering the hydrogen reforming system; self-controlled chemistry initiation and quenching; and low complexity.    DETAILED DESCRIPTION - A hydrogen reforming system comprises a cyclical compression chamber (200) having an entry port for receiving hydrogen-containing gas and an exit port for delivering reformed hydrogen-containing gas, where the cyclical compression chamber has an operational cycle with an internal pressure and temperature absent combustion effective for reforming the hydrogen-containing gas; a heating system for heating the hydrogen-containing gas to a non-combustible temperature; and a drive system for cycling the cyclical compression chamber.    An INDEPENDENT CLAIM is also included for a method for producing hydrogen by reforming hydrogen-containing gas, which involves introducing the hydrogen-containing gas into a cyclical compression chamber; increasing the pressure and temperature of the hydrogen-containing gas by reducing the volume of the cyclical compression chamber to initiate reformation chemistry; continuing the reformation chemistry in the cyclical compression chamber under conditions of pressure and temperature and in the absence of combustion effective to convert a portion of the hydrogen-containing gas into reformed hydrogen-containing gas; quenching the reformation chemistry by increasing the volume of the cyclic compression chamber; and discharging the reformed hydrogen-containing gas from the cyclical compression chamber.    DESCRIPTION OF DRAWING(S) - The figure shows the above hydrogen reforming system.    Internal combustion chamber (110)    Piston (112)    Cylinder (114)    Drive shaft (120)    Cranks (130)    Cyclical compression chamber (200)    Piston (205)    Cylinder (210)