TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Method: The operating temperature is (65 - 90, preferably 70 - 85) degrees C. The regeneration temperature is (150 - 250, preferably 175 - 225) degrees C. The at least partially deactivated composition is formed, when the carbon monoxide conversion is (less than 60, preferably less than 80, especially less than 99.9)%. In step (b), the feed stream is contacted with the at least partially deactivated composition at the regeneration temperature for (0.5 - 10, preferably 1 - 8, especially 2 - 7) hours.    TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Composition: The molar ratio of platinum to iron in the composition is 0.5:1 - 4:1. At least a portion of the platinum of the composition and the partially regenerated composition is in a reduced valence state. The composition further comprises a support selected from clay, alumina, silica, monolith, titania magnesium aluminate, magnesia and/or aluminosilicate. EXAMPLE - A PtFe/Al2O3 composition (2 g) was placed into a reactor and a feedstock containing (%) H2 (73.6), CO (0.93), CO2 (18.6), air (4.5) and H2O (2.4), was contacted with the composition at a rate of 524 cc/minute, at atmospheric pressure, at 80degreesC and the % carbon monoxide conversion versus the amount of time on the stream (a1) was measured. The composition was then regenerated comparatively by contacting with a pure hydrogen feed at a rate of 300 ml/minute, atmospheric pressure and 300degreesC for 2.5 hours. The temperature was then reduced to 80degreesC, the feedstock was then contacted with the composition and the % carbon monoxide conversion versus the amount of time on the stream (a2) measured. The composition was then again regenerated by a test method at 200degreesC, by contacting with the feedstock for 4.5 hours. The temperature was reduced to 80degreesC and the % carbon monoxide conversion versus the amount of time on the stream (a3) was measured. (a1), (a2) and (a3) were found to be approximately 66 to 99, 72 to 92 and 62 to 97, in approximately 537.5, 250 and 495 hours respectively. Thus the rate of carbon monoxide conversion after the composition was regenerated remained approximately the same and was similar to that obtained initially prior to the regeneration of the catalyst, in both the test and comparative regeneration methods. Thus the catalyst composition could be regenerated at a lower temperature and without the pure hydrogen feed.