The present invention relates, in general terms, to a composite membrane for use in filtration. The present invention also relates to a method of fabricating the composite membrane, and a method of filtrating using the composite membrane as disclosed herein. The method of fabricating a composite membrane comprising contacting a perfluorinated polymer solution with a surface of a polymer layer and drying the perfluorinated polymer solution at a relative humidity of less than 20% to form a perfluorinated polymer layer physisorbed on the surface of the polymer layer.

The present invention relates, in general terms, to a composite membrane for use in filtration. The present invention also relates to a method of fabricating the composite membrane, and a method of filtrating using the composite membrane as disclosed herein. The method of fabricating a composite membrane comprising contacting a perfluorinated polymer solution with a surface of a polymer layer and drying the perfluorinated polymer solution at a relative humidity of less than 20% to form a perfluorinated polymer layer physisorbed on the surface of the polymer layer.

The technology disclosed herein relates to a vent assembly having a vent housing that defines a first airflow pathway, a second airflow pathway, and a third airflow pathway. The first airflow pathway is configured for fluid communication with an interior of an enclosure. The second airflow pathway is configured for fluid communication with the external environment, and the third airflow pathway extends between the first airflow pathway and the second airflow pathway. A membrane is coupled to the vent housing such that the second airflow pathway and the third airflow pathway are in communication through the membrane. Coalescing filter media is disposed within the vent housing such that the third airflow pathway and the first airflow pathway are in communication through the coalescing filter media. The vent assembly defines a spacing region between the coalescing media and the membrane.

The technology disclosed herein relates to a vent assembly having a vent housing that defines a first airflow pathway, a second airflow pathway, and a third airflow pathway. The first airflow pathway is configured for fluid communication with an interior of an enclosure. The second airflow pathway is configured for fluid communication with the external environment, and the third airflow pathway extends between the first airflow pathway and the second airflow pathway. A membrane is coupled to the vent housing such that the second airflow pathway and the third airflow pathway are in communication through the membrane. Coalescing filter media is disposed within the vent housing such that the third airflow pathway and the first airflow pathway are in communication through the coalescing filter media. The vent assembly defines a spacing region between the coalescing media and the membrane.

Thin, self-supporting biaxially expanded polytetrafluoroethylene (ePTFE) membranes that have a high crystallinity index, high intrinsic strength, low areal density (i.e., lightweight), and high optical transparency are provided. In particular, the ePTFE membrane may have a crystallinity index of at least about 94% and a matrix tensile strength at least about 600 MPa in both longitudinal nd transverse directions. In addition, the ePTFE membrane is transparent or invisible to the naked eye through a complete conversion of the PTFE primary particles into fibrils. The ePTFE membrane may have a thickness per layer of less than 100 nm and a porosity reater than 50%. Further, the ePTFE membrane is stackable, which, in turn, may be used to control permeability, pore size, and/or bulk mechanical properties. The ePTFE membrane may be used to form composites, laminates, fibers, tapes, sheets, tubes, or three-dimensional objects. Additionally, the ePTFE membrane may be used in filtration applications.

Thin, self-supporting biaxially expanded polytetrafluoroethylene (ePTFE) membranes that have a high crystallinity index, high intrinsic strength, low areal density (i.e., lightweight), and high optical transparency are provided. In particular, the ePTFE membrane may have a crystallinity index of at least about 94% and a matrix tensile strength at least about 600 MPa in both longitudinal nd transverse directions. In addition, the ePTFE membrane is transparent or invisible to the naked eye through a complete conversion of the PTFE primary particles into fibrils. The ePTFE membrane may have a thickness per layer of less than 100 nm and a porosity reater than 50%. Further, the ePTFE membrane is stackable, which, in turn, may be used to control permeability, pore size, and/or bulk mechanical properties. The ePTFE membrane may be used to form composites, laminates, fibers, tapes, sheets, tubes, or three-dimensional objects. Additionally, the ePTFE membrane may be used in filtration applications.

The invention relates to a device for removing a gas from an aqueous liquid, particularly a blood liquid, comprising a first compartment permeated by the aqueous liquid during operation of the device; a second compartment permeated by a purging gas during operation of the device, the first compartment and the second compartment being separated from each other by a semipermeable membrane; and a third compartment permeated by a liquid proton donor during operation of device, said proton donor being an organic or inorganic acid, the first compartment and the third compartment being separated from each other by a membrane permeable to ions, and the membrane permeable to ions comprising at least one cation conductor.

A membrane is described for purifying or separating hydrogen from a multi-component gas stream such as syngas. This membrane uses a molecular pre-treatment, a transition metal, fluorine containing polymer, carbon fibers and carbon matrix sintered on a supportive screen. The membrane may be a bilayer membrane comprised of a layer containing high surface area carbon and another layer containing lower surface area carbon. Methods for purifying hydrogen are also described.

A membrane is described for purifying or separating hydrogen from a multi-component gas stream such as syngas. This membrane uses a molecular pre-treatment, a transition metal, fluorine containing polymer, carbon fibers and carbon matrix sintered on a supportive screen. The membrane may be a bilayer membrane comprised of a layer containing high surface area carbon and another layer containing lower surface area carbon. Methods for purifying hydrogen are also described.

Provided is a filtration method that includes a cleaning step and involves the use of a porous membrane, wherein the filtration method offers exceptional resistance to cleaning solutions (chemicals) (chemical liquid resistance) and exceptional filtration performance, and has a long service life. A filtration method includes the following steps: a filtration step in which a liquid to be processed that contains a material to be filtered is passed through a porous membrane configured from a resin having a three-dimensional mesh structure, and a filtrate is separated from the material to be filtered; and a cleaning step in which the porous membrane has a cleaning solution passed therethrough or is immersed in the cleaning solution so that the interior of the porous membrane is cleaned.