Patent classifications
B01D67/00111
HYDROPHILIC POLYMER AND MEMBRANE FOR OIL-WATER SEPARATION AND METHOD OF PRODUCING THE SAME
This invention relates to a hydrophilic polymer and membrane for oil-water separation. More particularly, this invention relates to a super hydrophilic polymer and membrane with zwitterionic property for oil-water separation, and method of producing the same. The hydrophilic polymer comprises polymer repeat units, each unit having at least one negatively charged carboxylic functional group and at least one positively charged amine functional group; and a monomer having a single aromatic ring and an imide functional group.
IMPROVED METHOD TO MAKE CARBON MOLECULAR SIEVE HOLLOW FIBER MEMBRANES
An asymmetric hollow fiber (CMS) carbon molecular sieve is made by providing a dope solution comprised of a polvimide and a solvent, at a temperature greater than 250 C. that is less than the storage modulus at a temperature of 250 C., but no more than ten times less as measured using dynamic mechanical thermal analysis from 250 C. to a temperature where the polyimide carbonizes. The polvimide is shaped into a hollow polvimide fiber, the solvent removed and the polyimide hollow fiber is heated to pyroiyze the polvimide and form the asymmetric hollow carbon molecular sieve. The asymmetric hollow fiber carbon molecular sieve has a wall that is defined by an inner surface and outer surface of said fiber and the wall has an inner porous support region extending from the inner surface to an outer raicroporous separation region that extends from the inner porous support region to the outer surface. Surprisingly, when the polyimide has the particular storage modulus characteristics, the method allows for the hollow fiber CMS to be made without any pre-treatmenis or additives to inhibit stractural collapse of the inner microporous region.
FABRICATION OF FILTRATION MEMBRANES
Disclosed is a method of preparing a filtration membrane. The method includes providing a copolymer solution by dissolving a statistical copolymer in a mixture of a co-solvent and a first organic solvent, coating the copolymer solution onto a porous support layer to form a polymeric layer thereon, coagulating the polymeric layer on top of the support layer to form a thin film composite membrane, and immersing the thin film composite membrane into a water bath to obtain a filtration membrane. Also disclosed are a filtration membrane prepared by the method, and a process of filtering a liquid using the filtration membrane thus prepared.
FABRICATION OF FILTRATION MEMBRANES
Disclosed is a method of preparing a filtration membrane. The method includes providing a copolymer solution by dissolving a statistical copolymer in a mixture of a co-solvent and a first organic solvent, coating the copolymer solution onto a porous support layer to form a polymeric layer thereon, coagulating the polymeric layer on top of the support layer to form a thin film composite membrane, and immersing the thin film composite membrane into a water bath to obtain a filtration membrane. Also disclosed are a filtration membrane prepared by the method, and a process of filtering a liquid using the filtration membrane thus prepared.
METHOD OF MAKING IMPROVED POLYIMIDE SEPARATION MEMBRANES
A polyimide separation membrane is comprised of a polyimide, a halogen compound (e.g., halogenated aromatic epoxide) that is soluble in the polyimide and a hydrocarbon having 2 to 5 carbons (e.g., ethane, ethylene, propane or propylene). The gas separation membrane has improved selectivity for small gas molecules such as hydrogen compared to polyimide membrane not containing the halogen compound or hydrocarbon. The polyimide separation membrane may be made by shaping a dope solution comprised of a polyimide, a halogen containing compound that is soluble in the polyimide, removing the solvent and then exposing the untreated polyimide membrane to a treating atmosphere comprising a hydrocarbon having 2 to 5 carbons for a sufficient time to form the polyimide membrane.
ACRYLONITRILE-BASED MEMBRANE WITH LOW THROMBOGENICITY
The present disclosure relates to improved semipermeable membranes based on acrylonitrile copolymers for use in dialyzers for the extracorporeal treatment of blood in conjunction with hemodialysis, hemofiltration or hemodiafiltration. The present disclosure further relates to methods of producing such membranes.
Method for the Production of Positively Charged Membranes
The present invention relates to a method for the production of a positively charged membrane. Furthermore the present invention relates to a positively charged membrane obtainable by the methods of present invention and the use of these positively charged membranes.
A METHOD FOR DIRECTLY GROWING ULTRATHIN POROUS GRAPHENE SEPARATION MEMBRANE
The invention, belonging to the field of membrane technology, presents a method for the direct growth of ultrathin porous graphene separation membranes. Etching agent, organic solvent and polymer are coated on metal foil, and then they are calcined at high temperature in absence of oxygen; after removal of metal substrate and reaction products, single-layered or multi-layered porous graphene membranes are obtained. Alternatively, the dispersion or solution of etching agent is coated on metal foil, on which a polymer film is then overlaid. The obtained sample is subsequently calcined at high temperature in absence of oxygen; after removal of metal substrate and reaction products, single-layered or multi-layered porous graphene membranes are obtained. The method involved in this invention is simple and highly efficient, and allows direct growth of ultrathin porous graphene separation membranes, without needing expensive apparatuses, chemicals and graphene raw material. Additionally, the graphene membranes prepared with this method have controlled pore size, ultrahigh water flux and strong resistance to irreversible fouling.
HYBRID POLYMERIC HOLLOW FIBER MEMBRANE, HYBRID CARBON MOLECULAR SIEVE HOLLOW FIBER MEMBRANE, AND PROCESSES FOR PREPARING THE SAME
The present invention relates to a polymeric hollow fiber membrane and a carbon molecular sieve hollow fiber membrane, both of which have excellent gas separation performance, and processes for preparing the same. Specifically, the present invention relates to a hybrid polymeric hollow fiber membrane that comprises a glassy polymer containing fluorine and a ladder-structured polysilsesquioxane, a hybrid carbon molecular sieve hollow fiber membrane prepared by pyrolysis thereof, and processes for preparing the same. The hybrid polymeric hollow fiber membrane and the hybrid carbon molecular sieve hollow fiber membrane according to the embodiments of the present invention are excellent in gas flux and selectivity and can have a large surface area per unit volume. Thus, they can be advantageously used for separating gases with a high energy efficiency on a large scale.
POROUS MEMBRANES
The present invention relates to a porous membrane, process for the manufacture thereof and uses thereof.