Abstract: The invention relates to a membrane pipe module, said module comprising a cylindrical housing containing a plurality of tubular membrane sections which extend in the axial direction and are interconnected at the ends thereof, forming longer tubular membrane sections. Said cylindrical housing comprises a heatable chamber, on one or both sides, comprising U-shaped connection pipes which are arranged therein and are guided through a separating wall between the chamber and the housing, with the two open ends thereof, and respectively connect two adjacent open tubular membrane sections, forming a membrane loop.

Abstract: Process for the continuous manufacture of tubular composite or multi-layer membranes comprising a porous sub layer (support layer), mainly determining the mechanical strength of the membrane, and adjacent to the support layer a second layer of a material of different chemical nature (separation layer), mainly determining the separation properties of the membrane, winding a respective flat sheet composite membrane lengthwise or spirally around a mandrel or shaft, into a tube or hose, the separating layer of the composite membrane facing to the inside of the tube or hose, gluing or welding the edges which may overlap or form a butt seam, and applying to said seam or overlapping area from the inside of the tube or hose a sealing material which can be solidified, and finally solidifying said sealing material.

Abstract: Process for the manufacture of composite plasma membranes with the production of a pore-free impermeable polymer layer on a porous substrate through the plasma polymerization of a gaseous mixture, said gaseous mixture containing a hydrocarbon as the matrix-forming component and a nitrogen-, silicon-, sulphur- or phosphorus-containing inorganic compound as the non-matrix-forming component and an oxygen-containing compound, by means of glow discharge in an electrical alternating field. The pore-free impermeable polymer layer is produced directly on a porous substrate without the use of an impermeable intermediate layer, said porous substrate having a pore diameter of less than 100 nm on the side facing the pore-free polymer layer. The composite plasma membranes are used for separating C.sub.1 -C.sub.3 alkanols from mixtures thereof with other organic liquids using the method of pervaporation.

Abstract: Composite membrane-for separating water from fluid mixtures containing organic components by means of pervaporation comprising a separating layer of cross-linked polyvinyl alcohol, which has been subjected to a post-cross-linking by treatment with acids acting in the vapor phase on the polyvinyl alcohol layer. The acids are preferably hydrohalic acids, sulfurous acid, sulfuric acid, nitrous acid, nitric acid or acetic acid.

Abstract: A multi-layer membrane having a porous backing layer of polyacrylonitrile, polysulfone or the like, and an active separating layer of polyvinyl alcohol or cellulose acetate. The membrane is particularly suitable or the separation of water-alcohol mixtures according to the pervaporation process.

Abstract: A multi-layer membrane having a porous backing layer of polyacrylonitrile, polysulfone or the like, and an active separating layer of polyvinyl alcohol or cellulose acetate. The membrane is particularly suitable for the separation of water-alcohol mixtures according to the pervaporation process.

Abstract: A membrane module is disclosed which comprises at least one elongated, planar membrane element which is composed of two membranes aligned opposite one another so as to define a closed cavity into which active surfaces of both membranes face. At both ends of the membrane element, separate conduits attached to the two membranes are in communication with the cavity, such that the feed flow from one conduit to the other through the cavity is radial, relative to the membrane element. The membrane element can be spirally wound around one or both of the conduits.

Abstract: A multi-layer membrane having a porous backing layer of polyacrylonitrile, polysulfone or the like, and an active separating layer of polyvinyl alcohol or cellulose acetate. The membrane is particularly suitable for the separation of water-alcohol mixtures according to the pervaporation process.