NOVELTY - Multi-cyclic method of operating a water-gas shift (WGS) reactor, comprising copper-based WGS catalyst, comprises flowing reactant gas comprising carbon monoxide and water through reactor to contact reduced WGS catalyst, while maintaining at operating 150-350 degrees C; purging WGS reactor with dry, first non-oxidizing gas at operating temperature; and heating the WGS catalyst to the operating temperature in a dry, second non-oxidizing gas.    USE - For operating a WGS reactor that is subject to frequent cycles of startups and shutdowns (claimed). Useful for the preparation of hydrogen for use in fuel cells.    ADVANTAGE - The method extends the useful operational lifetime of copper-based catalysts in applications.    DETAILED DESCRIPTION - A multi-cyclic method of operating a water-gas shift (WGS) reactor, comprising a copper-based WGS catalyst, comprises:    (a) heating the WGS catalyst in its oxidized state in a dry, reducing gas comprising a reducing component to 100-350 degrees C to form a reduced WGS catalyst;    (b) flowing a reactant gas comprising carbon monoxide (CO) and water (H2O) through the reactor to contact the reduced WGS catalyst, while maintaining the WGS catalyst temperature at operating temperature of 150-350 degrees C;    (c) purging the WGS reactor with a dry, first non-oxidizing gas at the operating temperature, allowing the WGS catalyst temperature to fall below the operating temperature;    (d) heating the WGS catalyst to the operating temperature in a dry, second non-oxidizing gas; and    (e) repeating steps (B)-(D) at least two times.    INDEPENDENT CLAIMS are also included for:    (a) a catalyst comprising: 5-20 wt.% of copper component, where at least 50 wt.% of the copper component is in the form of a copper oxide, aluminum oxide spinel; at least 75 wt.% of alumina; and 0.03-1 wt.% of carbonaceous residue; and    (b) conducting the water-gas shift reaction comprising contacting a reactant gas stream comprising carbon monoxide (CO) and water (H2O) with a WGS catalyst to form hydrogen gas (H2) and carbon dioxide (CO2).    DESCRIPTION OF DRAWING(S) - The figure shows a graph of a temperature versus time program that models a single catalyst operational cycle used in conducting the catalyst deactivation studies.