Abstract:
A package assembly comprising a sealed water-impermeable bag enclosing: a spiral wound filtration element comprising a piperazine-based membrane, and an aqueous solution comprises a substantially non-oxidizable buffer having capacity to sequester at least 0.0025 moles per liter of hydrogen ions. The assembly preferably further includes a reducing agent. The assembly provides improved preservation for piperazine-based membranes and elements incorporating such membranes.
Abstract:
A method for making a composite polyamide membrane comprising the steps of applying a polyfunctional amine monomer and polyfunctional acyl halide monomer to a surface of the porous support and interfacially polymerizing the monomers to form a thin film polyamide layer, wherein the method is includes at least one of the following steps: i) conducting the interfacial polymerization in the presence of a monomer comprising at least one phosphorous-containing functional group or salt thereof and an at least one amine-reactive functional group; and/or ii) applying such a monomer to the thin film polyamide layer.
Abstract:
The invention includes methods for testing membranes and membrane-based systems by introducing particles into a feed liquid passing across the surface of a membrane wherein the particles have a size larger than the nominal cut-off of the membrane, and measuring the presence of the particles within a permeate solution which passes through the membrane. In one embodiment, the particles are selected from those which dissolve within the permeate solution after being measured. In another embodiment, the particles are selected from inorganic salts. Many additional embodiments are disclosed.
Abstract:
A method for assembling an electrodeionization device comprising providing in a sequential arrangement: an anode, membrane cell assembly, cathode; wherein the membrane cell assembly comprises at least one sequential arrangement of: a cation exchange membrane, concentrating chamber, anion exchange membrane, diluting chamber, cation exchange membrane, concentrating chamber and anion exchange membrane. The method includes locating an ion exchange spacer in at least one chamber of the membrane cell assembly wherein an ion exchange spacer comprises an ion exchange resin and a dissolvable binder.
Abstract:
A method for making a composite polyamide membrane including the steps of applying a polyfunctional amine monomer and polyfunctional acid halide monomer to a surface of the porous support and interfacially polymerizing the monomers to form a thin film polyamide layer, wherein the method is includes at least one of the following steps: i) conducting the interfacial polymerization in the presence of an additional monomer comprising an aromatic moiety at least one carboxylic acid functional group or salt thereof and a single amine-reactive functional group; and/or ii) applying such a monomer to the thin film polyamide layer. Many additional embodiments are described including applications for such membranes.
Abstract:
A method for making a composite polyamide membrane comprising the steps of applying a polyfunctional amine monomer and polyfunctional acyl halide monomer to a surface of the porous support and interfacially polymerizing the monomers to form a thin film polyamide layer, wherein the method is includes at least one of the following steps: i) conducting the interfacial polymerization in the presence of a C2-C20 aliphatic monomer comprising at least one carboxylic acid functional group or salt thereof, and a single amine-reactive functional group; and ii) applying a C2-C20 aliphatic monomer comprising at least one carboxylic acid functional group or salt thereof, and a single amine-reactive functional group to the thin film polyamide layer. Many additional embodiments are described including applications for such membranes.
Abstract:
Various methods for testing spiral wound modules by thermal imaging are described. In a preferred embodiment, the method(s) includes flowing a gas between a scroll face and permeate collection tube of a spiral wound module and detecting temperature differences on the scroll face. Temperature differentials on the scroll face may be captured as a thermal image. The location(s) of temperature differentials on the scroll face can be correlated to defects in the module. In preferred embodiments, the subject test methods are non-destructive and can be applied to spiral wound modules in either a dry or wet condition.
Abstract:
A thin film composite polyamide membrane having a porous support and a thin film polyamide layer comprising a reaction product of m-phenylene diamine (mPD) and trimesoyl chloride (TMC), characterized by the thin film polyamide layer having a critical strain value of less than 10%. In another embodiment, the thin film polyamide layer has a modulus of greater than 0.75 (GPa). In yet another embodiment, the thin film polyamide layer has an equilibrium swelling value of at least 45%. In another embodiment, the thin film polyamide layer has a thickness of at least 230 nm.
Abstract:
A method for making a composite polyamide membrane including the steps of applying a polyfunctional amine monomer and polyfunctional acyl halide monomer to a surface of the porous support and interfacially polymerizing the monomers to form a thin film polyamide layer, wherein the method is includes at least one of the following steps: i) conducting the interfacial polymerization in the presence of a subject monomer comprising at least one carboxylic acid group linked to an aromatic moiety and wherein the aromatic moiety is further substituted with at least one of an acyl halide or anhydride functional group and ii) applying the subject monomer to the thin film polyamide layer. The invention includes many additional embodiments.
Abstract:
A thin film composite polyamide membrane having a porous support and a thin film polyamide layer comprising a reaction product of m-phenylene diamine (mPD) and trimesoyl chloride (TMC), characterized by the thin film polyamide layer having a critical strain value of less than 10%. In another embodiment, the thin film polyamide layer has a modulus of greater than 0.75 (GPa). In yet another embodiment, the thin film polyamide layer has an equilibrium swelling value of at least 45%. In another embodiment, the thin film polyamide layer has a thickness of at least 230 nm.