Abstract: A membrane tube is provided for the permeative separation of a gas from gas mixtures. The membrane tube has at least two membrane tube sections, each with a porous, gas-permeable, metallic, tubular support substrate, and a membrane which is selectively permeable for the gas to be separated off. The tube also has, applied to the support substrate around the circumference, at least one connecting section which is gastight at least on the surface and by way of which the two adjacent membrane tube sections are joined, and at least one spacer in the region of the connecting section. The spacer projects in the radial direction to above the membrane.

Abstract: An electro-chemical module has a porous plate-shaped metallic carrier substrate with a gas-permeable central region and a peripheral region. A layered construction is disposed in the central region on a first side of the carrier substrate. At least one metallic gas-tight housing part is by way of a welded connection connected to the peripheral region of the carrier substrate. A gas-tight zone extends from the layered construction up to the housing part. The gas-tight zone has a gas-tight surface portion which extends superficially from the layered construction on the first side of the carrier substrate at least up to the welded connection. The welded connection by which the gas-tight surface portion is connected in a gas-tight manner to the housing part and the welding zone of which extends only through part of the thickness of the carrier substrate.

Abstract: A plate-shaped, porous, carrier substrate produced by powder metallurgy for a metal-supported electrochemical functional device, includes a marginal region and a central region with a surface configured to receive a layer stack with electrochemically active layers on a cell-facing side of the carrier substrate. A surface section of the marginal region has a melt phase of the carrier substrate material on the cell-facing side of the carrier substrate. At least sections of a region located beneath the surface section having the melt phase have a higher porosity than the surface section disposed above them and having the melt phase.