PATENTS

12Membrane Technology October 2013

PATENTSSupported molecular sieve membrane

Applicant: Shell Internationale Research Maatschappij Bv, The NetherlandsIn one embodiment of this patent a method is disclosed that includes preparing a molecular sieve material, such as a silicoaluminophosphate (SAPO) and/or an aluminophosphate (AlPO) gel in a first chamber, and transferring this material from the first chamber to a second chamber, including a support. In the second chamber the support is brought into contact with the molecular sieve material. This is done under conditions that promote crystallisation of the molecular sieve material on the support. Crystals of the molecular sieve material are synthesised on the support. Transference of the molecular sieve material from the first chamber to the second one continues until a predetermined synthesis end-point is reached on the support.Patent number: WO/2013/020968Inventors: A. Agarwal, B.D. Murray, J.M. Mayne, C.E. Ramachandran and P.J. WilliamsPublication date: 14 February 2013

End-member for membrane element

Applicant: Nitto Denko Corp, JapanThis patent covers an end-member (3A) for a membrane element. It is provided with an inner peripheral part (31); an outer peripheral part (32), which surrounds the inner peripheral part (with a space between them); a plurality of connection parts (33) that connect the inner and outer peripheral parts; and a blocking plate (34), which is disposed between at least

one pair of connection parts (33) and forms an opening (41) with the outer peripheral part (32). This configuration enables a radially out-ward diffusion flow to be created by the block-ing plate (34). This enables suspended matter in the feed liquid to be effectively guided to the outer peripheral side.Patent number: WO/2013/021658Inventors:S.Chikura,Y.Uda and T. HamadaPublication date: 14 February 2013

Filtration membrane comprising polymeric nano-fibres

Applicants: California Institute of Technology, USA; and Korea Advanced Institute of Science and Technology, KoreaA filtration membrane comprising polymeric nano-fibres and/or micro-fibres is described. The fibres have a polymer component and a dendrimer component. Methods and systems are detailed that enable selective filtration of a liquid and, in particular, water or aqueous solutions.Patent number: WO/2013/023006Inventors: M.S. Diallo, W.A. Goddard, S.-J. Park and M. ChoPublication date: 14 February 2013

Dehydration system

Applicant: Mitsubishi Heavy Industries Ltd, JapanA dehydration system (and related method of dehydration) has been developed for carrying out regeneration of water separation membranes. This can be done whilst the system as a whole remains in operation. The design also enables fewer water separation membranes to be used. The dehydration system has at least one water separation membrane unit in operation, but is configured so that at least one water separation membrane unit is not in operation. Heated gas for regeneration processes is supplied to the flow path for the fluid to be treated using the mem-brane not in operation (and in a state in which the dehydration system is in operation). The water separation membrane is regenerated by the heated gas passing through its structure.Patent number: WO/2013/021966Inventors:Y.Tanaka,H.Osora, H. Nagano and H. HirayamaPublication date: 14 February 2013

Polymer blend membranes

Applicant: Arkema Inc, USAThis invention relates to a membrane formed from a blend of high molecular weight polyvinylidene fluoride (PVDF) (greater than

580 000 Mw) and low molecular weight PVDF (less than 580 000 Mw). Porous membranes, with an average pore size ranging from 5 nm to 100 µm, are made from this blend. According to the inventor, these materials show improved water permeability compared with membranes formed from a single Mw PVDF.Patent number: WO/2013/022660Inventor: W. KosarPublication date: 14 February 2013

Spiral-wound membrane distillation module and method

Applicant: General Electric Co, USAThis patent provides details of a spiral-wound membrane distillation module. The module comprises a central core element with an interior channel and a multilayer membrane assembly, spirally disposed around the cen-tral core element. The multilayer membrane assembly comprises at least a feed carrier layer; at least a vapour permeable, liquid-tight mem-brane layer; and at least a vapour spacer layer. Negative pressure is imparted to the latter. The membrane distillation module is configured to enable the feed solution to flow within the feed carrier layer, along an axial direction of the membrane distillation module, or enable the vapour to flow within the vapour spacer layer, again along an axial direction of the module, when it (the module) is used to divide a feed solution into a concentrated liquid and vapour. A method that makes use of this spiral-wound module to carry out membrane distillation is also described.Patent number: WO/2013/022591Inventors:A.P.Shapiro,H.Yang, X.Yu,T.A.Anderson,S.D.Kloos, C. Wang and H. LeiPublication date: 14 February 2013

Patent WO/2013/021658 provides details of a membrane element. A radially outward diffusion flow is created by the blocking plate (34), which enables suspended matter in the feed liquid to be guided to the outer peripheral side.

A schematic cross-sectional view of the spiral-wound membrane distillation module (100) in accordance with one embodiment of patent WO/2013/022591. The module is composed of a central core element (102) and a multilayer membrane assembly (104) that is spirally disposed around this central core element.

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October 2013 Membrane Technology13

Filter device with a quadrangular housing

Applicant: KSM Water GmbH, GermanyThis invention relates to a device for filtering water. It comprises a housing and multiple membrane filter elements that are arranged parallel to one another in this housing. Each membrane filter element has a plurality of channels that run in a longitudinal direction (with respect to the filter element). A mem-brane is attached on the inner face of each of these such that a permeate is produced outside the membrane filter element. The housing has a quadrangular cross-section.Patent number: WO/2013/021026Inventors: C. Goebbert, M. Volz, S. Kloos, J.E. Zuback, D. Ahlers and A. GrunskePublication date: 14 February 2013

Continuous recovery of CO2 from acidified sea water

Applicants: The Government of the United States of America as represented by the Secretary of the Navy; and Mele Associates Inc – USAThis patent provides details of a method for the continuous recovery of re-equilibrated [CO2]T from acidified natural sea water, using a membrane contactor. Sea water with a pH < 6 is passed over the outside of the hollow-fibre membrane tube whilst a vacuum, or a hydro-gen sweep gas, is applied to the inside of the membrane tube. According to the patent, up to 92% of the re-equilibrated [CO2]T can be removed from the natural sea water. The method described requires only a vacuum or sweep gas to recover low concentrations of CO2 from acidi-fied sea water (–50 mg/l). In the case of the vac-uum, CO2 can be concentrated in proportions needed for feedstock. When hydrogen is applied as the sweep gas, no additional energy penalty is required to recover CO2. The hydrogen/CO2 mixture produced in the acidification of the sea water can be used directly as a feedstock. Patent number: WO/2013/026068Inventors: F. Williams, J. Barile, F. Dimascio, D.R. Hardy and H.D. WillauerPublication date: 14 February 2013

Forward osmosis desalination device

Applicant: Absfil Co Ltd, KoreaThis invention relates to a fresh-water separator that employs a membrane distillation method, and a forward osmosis desalination system that is based on the fresh-water separator. In particular, this patent describes a desalination

system in which only a portion of a diluted draw solution is separated into gas and fresh water in the separator, whilst the other portion of the diluted draw solution is fed directly into a forward osmosis separator, so that the effi-ciency of both the sea-water separator and the desalination system are increased and energy consumption is reduced.Patent number: WO/2013/025012Inventors: S.J. Lee, S.M. Shim andJ.Y.ChoiPublication date: 21 February 2013

Membrane-based method for processing a bitumen stream

Applicant: Exxonmobil Upstream Research Co, USADisclosed is a method for processing bitumen streams using membrane filtration. In one aspect, membrane filtration replaces paraffinic froth treatment, with one or more filtration steps replacing gravity settling. In another, the bitumen stream is subjected to paraffinic solvent treatment at a high flow-rate, with an ‘‘almost cleaned’’ product being subsequently filtered by the membrane system. In this case, some con-taminants are removed by conventional gravity settling equipment, while additional contami-nants are removed by membrane filtration. In another aspect, membrane filtration is applied to a bitumen product effluent stream follow-ing naphthenic froth treatment. In another, it is applied to a bitumen product effluent stream from a solvent-based extraction process. In yet another aspect, membrane filtration is applied to a bitumen product effluent stream from a process involving solvent extraction with solids agglomeration. In still another aspect, membrane filtration is applied to bitumen produced by steam assisted gravity drainage (SAGD).Patent number: WO/2013/025260Inventors: J.A. Dunn, B.C. Speirs and A.SarkarPublication date: 21 February 2013

Method for recovering magnesium sulphate and producing magnesium oxideApplicant: Newamu IP Holdings Pty Ltd, AustraliaA method for recovering solid magnesium sulphate from a process solution containing dis-solved magnesium sulphate forms the subject of this patent. The method involves concentrating the process solution using membrane filtration. This forms a concentrated process solution. The concentrated process solution is then treat-ed to precipitate solid magnesium sulphate.Patent number: WO/2013/023254

Inventor: B.D. MullerPublication date: 21 February 2013

Vanadium-based alloy hydrogen separation membrane doped with boronApplicant: Korea Institute of Energy Research, KoreaThis patent provides details of a vanadium-based alloy, hydrogen-separation membrane, doped with boron, and a method of separation that uses this material. According to the inventors, the resulting hydrogen separation membrane has superior mechanical stability and high hydrogen permeability at elevated temperatures – enabling it to be used for capturing carbon dioxide, and separating hydrogen in pre-combustion carbon dioxide capturing processes.Patent number: WO/2013/024934Inventors: J.H. Park, E. Fleury, S.I. Jeon, H.-S. Chin, H.I. Baek, S.H. Choi and K.-T. ParkPublication date: 21 February 2013

Hollow-fibre filtration module

Applicant: Mann+Hummel GmbH, GermanyThis invention relates to a filtration module for fluids – in particular, a filtration module based on hollow-fibre membranes (82) for cleaning fluids (such as water) contaminated by foreign substances. A method of operating this module is also detailed. The patent describes a housing (12) that has a feed passage (28) for the inlet of the contaminated fluid (11). This passage is connected to what is referred to as the ‘‘unfiltered sides’’ of the hollow-fibre membranes (82). There is also a permeate pas-sage (24) for the discharge of the fluid (15) that

Patent WO/2013/023896 describes a filtration module for fluids – in particular, a filtration module based on hollow-fibre membranes (82) for cleaning fluids contaminated by foreign substances.

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14Membrane Technology October 2013

has been freed of foreign substances. This pas-sage is connected to the ‘‘filtered sides’’ of the hollow-fibre membranes. The membranes (82) seal off the feed passage (28) from the permeate passage (24). Each membrane (82) is secured at (at least) one open end (84) on a terminat-ing element (78). The internal chambers of the hollow-fibre membranes (82) are connected to one of the passages (24) via the open ends (84). Closed sections (82b) of the membranes are arranged in a chamber (38) of the hous-ing. This chamber is connected to the another passage. The terminating element contains a passage (28) to the chamber (38) – the passage being connected to radially running distributor channels (61) which have a plurality of distrib-utor openings (66, 68) entering the chamber.Patent number: WO/2013/023896Inventors: M. Micke, M. Fasold, J. Bolda and P. SuckfüllPublication date: 21 February 2013

Modified sulfonated block copolymers and their preparationApplicant: Kraton Polymers US Llc, USAThis patent describes modified sulfonated block copolymers that comprise at least two polymer end A blocks, and at least one poly-mer interior B block. Each A block contains essentially no sulfonic acid or sulfonate func-tional groups, whilst each B block consists of sulfonation susceptible monomer units and, based on the number of these sulfonation susceptible monomer units, about 10 mol% to around 100 mol% of a functional group according to the formula: -SO2-NR1R2 (or its salt). Methods for making these materials and ways of using them, for example, as a mem-brane for electrically or osmotically driven applications, are also detailed by this patent.Patent number: WO/2013/025271Inventor: C.L. WillisPublication date: 21 February 2013

Method for manufacturing a membrane for carbon dioxide separationApplicant: Nitto Denko Corp, JapanThis invention concerns a carbon dioxide separation membrane that has a graft in which a substituent is selectively introduced to car-bon dioxide, and that possesses a high separa-tion function for the gas. The patent provides details of a method for manufacturing this membrane. This involves: a step during which a polymer film is exposed to radiation; a step for forming a graft on the polymer film that has been exposed to radiation (the graft being

a monomer as a repeating unit, having a sub-stituent capable of forming a salt with fluoride ions); and a step for treating the substituent capable of forming a salt with fluoride ions, with a fluoride salt, to form a salt with fluo-ride ions in the substituent.Patent number: WO/2013/024594Inventors: N. Kimura, H. Emori, H. Nishii and T. ShintaniPublication date: 21 February 2013

Semipermeable filtration membrane with an integrated ozone-producing circuitApplicant: Ozomax Inc, CanadaThe proposed concept – the subject of this patent – is to integrate an ozone-producing circuit with the active surface of a semiper-meable filtration membrane. The circuit will create ozone and other mixed oxidants directly at the active surface of the membrane using the liquid to be purified as the elec-trolyte. The ozone and the mixed oxidants will prevent bio-film formation by killing the microorganisms and chemically breaking down the relatively large organic molecules in

the bio-film. No outside source of gas is nec-essary. The ozone and the mixed oxidants can also oxidise some of the dissolved gases to transform them into non-harmful and non-clogging by-products. The filtration mem-brane (102) includes an ozone-producing circuit (120) that has a plurality of electri-cally conductive lines (122 & 124). These are disposed directly on the active surface (102a) of the membrane. The electrically conductive lines are spaced-apart and form interleaved anodes (122) and cathodes (124). Ozone and other mixed oxidants coming from the ozone-producing circuit (120) will prevent the formation of bio-film (or remove it) on the active surface (102a) without the need for an outside source of gas. They can also remove at least some undesirable dissolved gases from the liquid being purified.Patent number: WO/2013/023289Inventors: A. Salama and M. SalamaPublication date: 21 February 2013

High recovery drinking-water process

Applicant/Inventor: R.A. Al-Samadi, CanadaDisclosed is a process that uses reverse osmosis (RO) or nanofiltration (NF) membranes and ion-exchange (IX) water softening resins to maximise the production of drinking water, purified industrial service water or recycled purified municipal or industrial effluents. The membrane and ion-exchange units are config-ured in a manner that enables the system to operate at high permeate recoveries of 90–99%, thus producing purified drinking water with a minimum volume of wastewater, and minimal membrane cleaning or less frequent membrane replacement. The process mitigates membrane fouling and scale formation, and minimises the use of water treatment chemicals, including acidic and alkali solutions, and sodium chlo-ride salt, normally required to regenerate the IX resin. The inventor says that this process is considerably better than ‘‘Whole Home RO’’ drinking water prior art, where the membrane permeate recovery is normally limited to 30–50% – by producing drinking water more efficiently and in a cost-effective manner.Patent number: WO/2013/023282Publication date: 21 February 2013

Electro-kinetic membranes

Applicant: Osmotex Ag, SwitzerlandAn electro-osmotic liquid transport membrane is described by this patent. The membrane is flexible and comprises first and second conduc-tive layers that are porous. A porous layer is positioned between the first and second con-

A semi-schematic side view of the filtration membrane proposed by patent WO/2013/023289, and an example of a device that uses it.

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October 2013 Membrane Technology15

ductive layers, and has pores defined by pore walls. Optionally the porous layer has a web-like or a foamy structure, or contains cylindri-cal pores.Patent number: WO/2013/026829Inventor: T. HeldalPublication date: 28 February 2013

Method for treating acidic leach liquors

Applicant: Newamu IP Holdings Pty Ltd, AustraliaA method for separating multivalent species from monovalent species in an acidic leach solution has been developed. The method involves passing the acidic leach solution through a membrane in a membrane treat-ment step in order to generate a membrane permeate and a membrane retentate. The method described also involves recovering the membrane permeate, containing the mono-valent species, and collecting the membrane retentate, containing the multivalent species.Patent number: WO/2013/026093Inventor: B.D. MullerPublication date: 28 February 2013

Water treatment apparatus

Applicant: Toray Industries Inc, JapanThe purpose of this invention is to create a water-treatment apparatus that is capable of preventing the failure of semipermeable mem-branes caused by excessive back-pressure. The patent describes a water-treatment apparatus that separates permeate water and concentrated water. The water to be treated is supplied to the membrane element (containing the semiper-meable membrane). The apparatus has a unit

that measures the pressure differential of the permeate water and concentrated water, and a pressure-release unit that operates in response to the pressure differential and releases the per-meate water pressure.Patent number: WO/2013/027804Inventors: H. KuboPublication date: 28 February 2013

Haemodialysis deviceApplicant: Bar-Ilan University, IsraelSome embodiments of this invention cover a device that is configured for selective removal of target substances from a patient’s blood. The device comprises an inlet, configured for letting the blood into the device; an outlet, configured for removing blood from the device; and a chamber adapted for containing fluid. Particles disposed in the chamber are adapted to enable them to selectively bind to the target sub-stances. Target substances move from the blood across a membrane into the chamber. This membrane has pores that are small enough to prevent the particles from entering the blood. The pores are small enough to prevent cellular components from entering the chamber, but are large enough to enable molecules with a size of at least 25 000 Dalton to enter the chamber.Patent number: WO/2013/027214Inventors:R.PopovtzerandY.MachteyPublication date: 28 February 2013

Combined acoustic MF and phononic crystal membrane particle separationApplicant: Flodesign Sonics Inc, USAA system has been developed that includes one or more acoustic microfiltration (MF) devices through which flows a mixture of a fluid and particulate. These selectively filter particles from the fluid. Also discussed are one or more phononic crystal units coupled to the acoustic microfilter(s) to further selec-tively filter particles from the fluid. Related apparatus, systems, techniques and articles are also described by this patent.Patent number: WO/2013/028733Inventors: E.A. Rietman, B. Lipkens and J. DionnePublication date: 28 February 2013

Composite membrane formed from a polymer blend including self-assembling block copolymers

Applicant: Dow Global Technologies Llc, USAA method for making a composite membrane is detailed by this patent. It includes form-ing, on a surface of a porous support, a dis-criminating layer. Various steps are involved. These include forming a polymer blend comprising a ‘‘blending’’ polymer and a block copolymer composed of durable segments that form a co-continuous phase with the blending polymer and fugitive segments that form self-assembled micro-domains within the co-continuous phase. At least a portion of the fugitive segments is removed to yield pores having an average size of less than or equal to 0.5 µm.Patent number: WO/2013/028308Inventors: S.G. Gaynor, D.J. Murray, C.H.Silvis,Y.N.Srivastava andJ.YangPublication date: 28 February 2013

Removal of boron from saline water using NF membrane pretreatment

Applicants: A.E.Z. Abdellatif, Egypt; Saline Water Desalination Research Institute, Saudi Arabia; and Saline Water Desalination Research Institute Global Patent Trust, USAThis patent covers the removal of boron from saline water, using alkalised nanofiltration (NF) membrane pretreatment – adopted at 90% recovery and pH 8–9.5–to produce softened and alkalised NF permeate with a SDI < 1 and a significant reduction in feed boron, TDS and scale-forming ions (depending on the proper-ties of the NF membrane’s polymer structure). NF acts as a partial desalination process, a softening process and a boron removal process. Additional reverse osmosis (RO) membrane alkalisation can be adopted over a wide range of RO feed conditions at pH 8.5–10, resulting in the production of desalinated water with almost nil boron content.Patent number: WO/2013/032528Inventor: A.E.Z. AbdellatifPublication date: 7 March 2013

An electro-osmotic liquid transport membrane is described by patent WO/2013/026829. The mem-brane has a glass-fibre porous layer (1); a first conductive layer (2), in the form of metal-coated glass-fibre; and a second conductive layer (3) (also in the form of metal-coated glass-fibre).