Abstract: The present disclosure is concerned with negatively charged filtration membranes and methods of making and using same, for example, in the concentration and/or filtration of dairy products. This abstract is intended as a scanning tool for purposes of searching in the particular art and is not intended to be limiting of the present invention.

Abstract: Selective, water-permeable membranes for reverse osmosis and nanofiltration are prepared by interfacially polymerizing on a microporous support an essentially monomeric bipiperidine reactant, and an essentially monomeric amine-reactive polyfunctional aromatic or cycloaliphatic acyl halide having on the average at least about 2 acyl halide groups per reactant molecule. The polymerization is optionally carried out in the presence of a monomeric amine salt, which can increase the flux rate of the resulting membrane.

Abstract: Water permeable reverse osmosis membranes are prepared by interfacially polymerizing on a microporous support an essentially monomeric polyamine reactant having at least two amine functional groups per reactant molecule, and an essentially monomeric amine-reactive polyfunctional aromatic or cycloaliphatic acyl halide having on the average at least about 2 acyl halide groups per reactant molecule. The polymerization is optionally carried out in the presence of a monomeric amine salt, which increases the flux rate of the resulting membrane. Preferred polyamine compounds of the generic formula, which are novel per se, include 3,5-diaminobenzoyl piperazine, 4-aminobenzoyl piperazine, 3-aminobenzoyl piperazine, isophthaloyl piperazine, and terephthaloyl piperazine.

Abstract: Water permeable reverse osmosis membranes are prepared by interfacially polymerizing on a microporous support an essentially monomeric polyamine reactant having at least two amine functional groups per reactant molecule, and an essentially monomeric amine-reactive polyfunctional single ring cycloaliphatic acyl halide having fewer than six carbon atoms per ring and having on the average at least about 2.2 acyl halide groups per reactant molecule. The polymerization is preferably carried out in the presence of a monomeric amine salt, which increases the flux rate of the resulting membrane. In addition, an aromatic polyfunctional acyl halide may be used in conjunction with the cycloaliphatic acyl halide in order to increase salt rejection rates. Preferred cycloaliphatic acyl halides are 1-cis, 2-trans, 3-cis, 4-trans-cyclopentane tetracarboxylic acid chloride, 1-cis, 2-trans, 3-cis, 4-trans-cyclobutane tetracarboxylic acid chloride and 1-cis, 2-trans, 4-cis-cyclopentane tricarboxylic acid chloride.

Abstract: Water permeable reverse osmosis membranes are prepared by interfacially polymerizing on a microporous support an essentially monomeric polyamine reactant having at least two amine functional groups per reactant molecule, and an essentially monomeric, at least trifunctional cyclic chloroformate amine-reactive reactant, wherein at least one of the functional groups is a chloroformyl group and the remaining functional groups of the amine-reactive reactant, if any, are acyl halides. The polymerization is preferably carried out in the presence of a monomeric amine salt, which increases the flux rate of the resulting membrane. In addition, an aromatic polyfunctional acyl halide and/or a polyfunctional cycloaliphatic acyl halide may be used in conjunction with the cyclic chloroformate in order to increase flux rates and possibly other desired properties. A preferred cyclic chloroformate is 5-chloroformyl isophthaloylchloride.

Abstract: The invention provides a novel thin film composite or coated membrane suitable for reverse osmosis, ultrafiltration and microfiltration applications, and having a porous polymeric substrate with one or more microporous layers to which a thin film or coating comprising a sulfonated polyarylether is attached substantively to provide an oxidatively stable, thin hydrophilic film or coating layer, and a method for manufacturing and using the same.

Abstract: The present invention relates to an interfacially synthesized reverse osmosis membrane useful for the separation of fluid mixtures and solutions. In particular, the present invention relates to a polyamide water permeable membrane containing a monomeric amine salt therein, which is useful for desalination of an aqueous solution. The present invention also relates to processes for preparing the membrane.

Abstract: The present invention relates to an interfacially synthesized reverse osmosis membrane useful for the separation of fluid mixtures and solutions. In particular, the present invention relates to an aromatic polyamide water permeable membrane containing an amine salt therein, which is useful for desalination of an aqueous solution. The present invention also relates to processes for preparing the membrane.