(US5316747-A)      CO is selectively oxidised to CO2, by (a) introducing O2-contg. into a mixt. contg. H2, CO2 and CO; (b) contacting this with a catalyst in a reaction chamber contg. and inlet and an outlet; and (c) introducing further 02(-contg. gas) into the chamber through 1 or more sec. inlet located between the other inlet and outlet.    Pref. catalyst is adsorbed onto pellets to form active pellets, such that catalyst concn. on them varies among different parts of the chamber to vary the oxidn. rate among these parts.    ADVANTAGE -   Reverse water-shift reaction is suppressed.    (JP7502205-W)      The selective oxidn of CO to CO2, the CO being in a gaseous mixt of H2, CO2 and CO, comprises: (i) introducing a first amt or O-contg gas into the mixt, (ii) contacting the gaseous mixt with a catalyst in a reaction chamber having a first inlet and first outlet, the catalyst promoting oxidn of CO to CO2 and (iii) introducing a further amt of O2 or O-contg gas into the chamber through at least one sec inlet located between the first inlet and outlet.    USE/ADVANTAGE -   For selectively oxidising CO in gaseous mixt. Esp useful for H-based fuel cell. Suppresses reverse water-shirt reaction, reduces amt of CO in H-contg gas stream to a level suitable for use in electrochemical fuel cells.    (US5456889-A)      Isothermal reactor (10) has a fin block (13) having an inner surface and outer surface, heat transfer surfaces extending perpendicularly from the inner surface, and tubing (20) which acts as an internal passageway for circulating a thermal fluid through it for supplying heat to or removing heat from the reactor (10).    Air distribution plate (14) has inside and outside surfaces. The plate's inside surface is positioned perpendicular to and in contact with the heat transfer surfaces to form a labyrinthine channel (22) between the inner surface of fin block (13) and inside surface of plate (14).    Channel (22) contains catalyst pellets and has an inlet and outlet. The plate (14) has gas distribution ports for introducing O-contg. gas into the channel (22) and an inlet port in fluid communication with the channel's (2) inlet. First end plate (11) is adjacent the outer surface of fin block (13). A second end plate (15) is next to the outside surface of fin block (13). Second end block (15) has ports in fluid communication with the gas distribution ports and a reactant gas inlet in communication with the inlet port. Stainless steel containment shell (12) is interposed between the end plates (11, 15). Shell (12) circumscribes the fin block (13) and the gas distribution plate (14). Shell (12) and end plates (11, 15) are attached to form a pressure tight assembly.    USE/ADVANTAGE -   isothermal reactor, for selectively oxidising the CO present in a mixt. of H contg. gas mixt. including H to CO2, reduces the amt. of CO in H contg. gas stream to a level suitable for use in a electrochemical fuel cell. The casting of the coil into the Al block offers a simple temp. rated pressure boundary for thermal fluids. The arrangement of the Al reactor inside a stainless steel shell means the al reactor housing is light wt. and provides effective thermal conductivity. The stainless steel shell is able to withstand the stress developed by the pressurized gases within the reactor and also resists corrosion, both of which are partic. problematic at elevated temps.