NOVELTY - A microbial fuel cathode assembly comprises a catalyst (6) and an electrically conductive catholyte wicking member (5) having a catalyst contacting surface (5a), an electrical contact region (5c) and a catholyte supply region (5b) to receive catholyte from a catholyte supply (9). The wicking member is operable to wick received catholyte from supply region to form a film of catholyte on a part of catalyst surface such that a part of catalyst surface is in contact with film of catholyte and a part of catalyst surface is in contact with a gas pathway arranged to supply oxygen to catalyst.    USE - As a cathode assembly for in a microbial fuel cell (claimed) useful in biological processes.    ADVANTAGE - The wicking member automatically supplies catholyte to the catalyst contacting area, thus avoiding wastage of generated power. The use of a film of catholyte on a part of the surface of the catalyst provides better communication with the catholyte than in a standard air facing cathode. As the catholyte wicking member is electrically conductive, the electrical contact region is in electrical communication with the catalyst. Therefore, the catholyte wicking member facilitates the electrical connection to the catalyst to form a circuit with an anodic zone; and facilitates the supply of catholyte to the catalyst. The cathode assembly enables catholyte to drain from the catalyst, so that fresh catholyte can be supplied to the catalyst and spent catholyte can be drained from the catalyst on a continuous basis. As a result, the accumulation of salt precipitate in or on the electrically conductive catholyte wicking member is reduced or avoided. The microbial fuel cell cathode assembly having wicking member, improves current density generation, operating lifetime, oxygen transport to the cathodic catalyst, electrical capacity per unit mass and equilibrium potential.    DETAILED DESCRIPTION - A microbial fuel cell cathode assembly comprises a catalyst (6) and an electrically conductive catholyte wicking member (5) having a catalyst contacting surface (5a) in contact with the catalyst, an electrical contact region (5c) for contacting an electrical connector, and a catholyte supply region (5b) for receiving catholyte from a catholyte supply (9). The electrically conductive catholyte wicking member is operable to wick received catholyte from the catholyte supply region to form a film of catholyte on a part of the surface of the catalyst such that a part of the surface of the catalyst is in contact with the film of catholyte and a part of the surface of the catalyst is in contact with a gas pathway arranged to supply oxygen to the catalyst. The catalyst comprises catalytic granules and at least some of the catalytic granules have a surface portion which is in direct contact with the gas pathway and a surface portion which is in direct contact with the catholyte film. The catalytic granules comprise a conductive substrate and catalyst. INDEPENDENT CLAIMS are included for the following:    (1) microbial fuel cell comprising the cathode, the catholyte supply in liquid communication with the electrically conductive catholyte wicking member for the transport of catholyte to the catalyst, and a cathodic electrical connection in electrical communication with the electrically conductive catholyte wicking member for the transport of catholyte to the catalyst;    (2) operating the microbial fuel cell involving changing the catholyte supplied to the electrically conductive catholyte wicking member, to change the catholyte at the catalyst contacting surface; and    (3) supplying oxygen and catholyte to a catalyst comprising catalytic granules in a microbial fuel cell cathodic assembly, involving bringing the catalytic granules into contact with a catalyst contacting surface of an electrically conductive catholyte wicking member having a catalyst contacting surface, an electrical contact region for contacting an electrical connector and a catholyte supply region for receiving catholyte from a catholyte supply; and wicking catholyte to the catalyst contacting surface through the electrically conductive catholyte wicking member to form a film of catholyte on a part of the surfaces of the catalytic granules such that a part of the surfaces of the catalytic granules is in contact with the film of catholyte and a part of the surfaces of the catalytic granules is in contact with a gas pathway arranged to supply oxygen to the catalyst.    DESCRIPTION OF DRAWING(S) - The figure shows a schematic sectional view of a cathode assembly.    Catholyte wicking member (5)    Catalyst contacting surface (5a)    Catholyte supply region (5b)    Electrical contact region (5c)    Catalyst (6)    Catholyte supply (9)