PatentsSelectively permeable compositemembrane structures Applicant: Compagnie d’Etude des Techniquesde l’Hydrogene, FranceThis invention relates to a composite structurethat consists of a relatively long filtration bar.From the outside inwards, it comprises an ultra-thin layer that is selectively permeable to hydro-gen and made from palladium or silver alloy.This layer is disposed on a permeable, rigid,refractory substrate consisting of a more or lesssolid body which is covered with an intermediarythin layer that has a relatively smooth surface.The body and the intermediary layer are made,respectively, by sintering with fine and ultra-fineInconel grains. A rigid metallic axial structure isembedded in the body. Veinlets, which are madein the body through the destruction of thermo-destructible wires during sintering, increase thepermeability of the substrate. The resulting com-posite membrane structure is particularly applic-able in hydrogen-producing combustible gasprocessors.Patent number: WO 02/066144Inventors: C. Etievant, F. Gaillard, D. DeLapparent, R. Le Cren, K. PointetPublication date: 29 August 2002

Filter bodyApplicant: AAflowsystems GmbH & Co Kg,GermanThis invention describes a method for producinga membrane filter body. It comprises the follow-ing steps: at least one porous functional layerthat is made of zeolitic particles is provided. Aliquid is applied to this functional layer, contain-ing precursors suitable for forming a zeolite. Thefunctional layer and the liquid are subjected topressure and a specific temperature in order toform a closed molecular screening layer.Patent number: WO 02/066141Inventors: S. Benfer, D. Bläse, H.-P. Feuerpeil, J.Hoffmann, H. Olapinski, B. Seling, G. TomandlPublication date: 29 August 2002

Electrocatalytic composition Applicant: De Nora Elettrodi SpA, ItalyAn oxygen-depolarized cathode for aqueoushydrochloric acid electrolysis membrane cells isthe subject of this patent. The cathode is placedin contact with the membrane, and is capable ofpreventing the release of hydrogen into oxygeneven at the highest current densities. Thehydrochloric acid may also be of technical gradewith a concentration limited to 15%, while theoperating temperature must not exceed 60°C.The cathode contains a mixture of rhodium sul-phide and a metal of the platinum group that isapplied in a single layer, or alternatively it isapplied separately in two distinct layers.

Patent number: 6 September 2002 Inventors: N.G. Martelli, F. FulvioPublication date: WO 02/068722

Membrane separation for sulphurreductionApplicant: W.R. Grace & Co–Conn, USAA membrane process for the removal of sulphurspecies from a naphtha feed, in particular, a FCClight cat naphtha, without a substantial loss ofolefin yield is disclosed. The process involvescontacting a naphtha feed stream with a mem-brane having sufficient flux and selectivity toseparate a sulphur-deficient retentate fractionfrom a sulphur-enriched permeate fraction,preferably, under pervaporation conditions.Sulphur-enriched permeate fractions containaromatic and non-aromatic hydrocarbons andare further treated with conventional sulphurremoval technologies, for example, hydro-treat-ing, to reduce the sulphur content. The processdescribed in this invention provides high qualitynaphtha products having a reduced sulphur con-tent and a high content of olefin compounds.Patent number: WO 02/068568Inventors: S.L. White, R.F. Wormsbecher, M.LesemannPublication date: 6 September 2002

Cleaning system for membrane modulesApplicant: VA Tech Wabag DeutschlandGmbH & Co Kg, GermanyA method and a associated system for cleaningmembrane modules has been developed. It isdesigned to be used in a water treatment plant.According to method, the membrane modulesare transferred from the water treatment plantinto a cleaning container, in which they arechemically cleaned. This container is sealed onceafter at least one module has been introduced,and a cleaning programme is carried out. Thiscleaning programme includes a step that involvesmechanically cleaning the membrane module byspraying it with a cleansing agent. This is nor-mally carried out before the chemical cleaningstep. In this was the membranes are cleaned in asimple manner with minimal use of chemicalsand negligible production of waste material.Patent number: WO 02/068102Inventors: A. Kraft, H. Kohl, F. KlegrafPublication date: 6 September 2002

Polymeric membranes Applicant: Gradipore Ltd, AustraliaA polymer membrane suitable for use in elec-trophoresis is formed from a pre-polymer havinga larger number of crosslinkable moieties. Thesemoieties are crosslinked with a polyfunctionalcrosslinking agent.Patent number: WO 02/068100Inventors: K.H. Purss, M.J. Caulfield, D.H.Solomon Publication date: 6 September 2002

Membrane reactor for gas extractionApplicant/Inventor: R.E. BuxbaumThe membrane reactor that is presented in thisinvention generates a desired gas such as hydro-gen. This is produced by steam reforming liquidfuels. The membrane reactor provides thermalintegration between the heating source and thereaction catalyst by heat conduction through asolid medium. A gas purification system extractsenergy from the waste gases to heat the mem-brane reactor.Patent number: WO 02/068092Publication date: 6 September 2002

Hydrophobic composite palladiummembrane catalyst Assignee: Council of Scientific & IndustrialResearch, USAA hydrophobic composite palladium-membranecatalyst, useful for the nonhazardous direct oxi-dation of hydrogen by oxygen to hydrogen per-oxide (without a gas phase mixing of hydrogenand oxygen or air) has been developed. It is‘described’ by the general formula: HPM(c)/SOMF (b)/Mx Pd1–x (a)/IPM. The patentexplains the various parts of this formula as fol-lows: IPM is an inorganic porous membrane; MxPd1–x is a metal alloy, permeable only to hydro-gen gas; Pd is palladium metal; M is a metalother than palladium, or a mixture of two ormore metals; x is a mole fraction of the metal Min the metal alloy (Mx Pd1–x), a is the weight ofthe metal alloy per unit area of IPM; SOMF is asurface oxidized thin metal film comprising pal-ladium; b is a thickness of SOMF; HPM is ahydrophobic polymer membrane; and c is aweight of the HPM per unit area of SOMF. Aprocess for producing the catalyst is detailed inthe patent. Patent number: US 6448199 Inventors: V.R. Choudhary, S.D. Sansare, A.G.Gaikwad Publication date: 10 September 2002

Polymer membrane productionApplicant: Celanese Ventures GmbH, GermanyThe invention relates to a polyazole based acid-doped polymer membrane. It also providesdetails of a method for the production and theuse of this membrane. The acid-doped polymermembrane can be used in a variety of ways onaccount of its excellent mechanical properties.The patent claims that it is especially suitable foruse in polymer-electrolyte-membrane fuel cells.Patent number: WO 02/071518Inventors: O. Uensal, J. Kiefer, J. Baurmeister, J.Pawlik, W. Kraus, F. Jordt Publication date: 12 September 2002

Multi-membrane filter Assignee: Siemens Westinghouse Power Corp,USAA filter element that is made up of a large num-ber of membrane layers is the subject of this

PATENTS

11Membrane Technology October 2002