Abstract: A membrane support usable for separative procedures is disclosed. The support is a mechanically solid composite carbon-carbon material of limited thickness in the passage direction Z of a flow to be treated, which composite has a porous texture appropriate for the membrane, with a fibrous substrate and a porous carbon-containing matrix. To increase the permeability and reduce the roughness of the outer surface of the support to be brought into contact with the membrane, the fibrous substrate is a carbon fibre mat of carbon fibre segments contained in a plane perpendicular to the Z axis and randomly oriented in that plane. Optionally a fraction of the support to be in contact with the membrane contains an inert fine powder dispersion making it possible to adjust the diameter of the pores of the outer face of the support. Also disclosed is a process for the production of this membrane support and its use as a membrane support and as a filtering element without the addition of a membrane.