Abstract: A filter assembly (10) including a first (12) and second (14) filtration element positioned in an abutting end-to-end arrangement along a common axis (X). Both filtration elements (12, 14) include a cylindrical housing (16, 16?) enclosing a filtration media and extending along the axis (X) between opposing ends, and an end cap (18, 20, 18?, 20?) located at each of the abutting ends of the filtration elements (12, 14) and comprising an annular surface (28, 28?) co-extensive with the housing (16, 16?) and an annular stepped edge (29, 29?). The first (12) and second (14) filtration elements are positioned with their end caps (18, 20?) directly engaged with each other so that the stepped edges (29, 29?) collectively form a continuous annular groove (31) about the periphery of the filter assembly (10). The annular groove (31) provides an effective means for handling filtration elements without increasing the overall length of end cap.

Abstract: A filtration element including a cylindrical housing enclosing a fluid filtration media extending along an axis (X) between opposing ends with a first and second end cap located at each end, wherein each end cap includes: i) an annular surface co-extensive with the housing, and ii) outer face laying in a plane perpendicular with the axis (X). The outer face of at least one end cap comprises an annular groove. A face seal including a base is located within the annular groove. A flexible lip extends axially from the base and axially beyond the outer face of the end cap and is adapted to engage with an abutting outer face of an end cap of an adjacently positioned filtration element.

Abstract: A hydroclone including: a vortex chamber (24) in fluid communication with the inlet (14), a process fluid chamber (32) in fluid communication with the process fluid outlet (20), an effluent separation chamber (30) located between the vortex chamber (24) and process fluid chamber (32) and including an outer circumferential surface (23), a vortex flow barrier (34) located between the vortex chamber (24) and the effluent separation chamber (30), an effluent barrier (36) located between the effluent separation chamber (30) and the process fluid chamber (32) including at least one opening (42?) near the outer circumferential surface (23), and an effluent opening (38) centrally located within the effluent separation chamber (30) in fluid communication with the effluent outlet (18); wherein the effluent separation chamber (30) has a median distance (80) between the vortex flow barrier (34) and effluent barrier (36) which is adjustable.

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: The present invention is an improved feed spacer, spiral wound element incorporating said feed spacer, filtration system and a method for making and using the same. In one embodiment the present invention includes an improved spiral wound element having: a central collection tube with a plurality of openings along its length to receive permeate; at least one filtration envelope extending outwardly from and wound about the tube and at least one feed spacer sheet wound about the collection tube wherein the feed spacer sheet being in planar contact with the outer surface of at least one filtration envelope.

Abstract: A microporous polyetheretherketone (PEEK) membrane in the form of films and hollow fibers formed without sulfonating the PEEK polymer. Solid fibers and articles are also claimed. A method of making membranes, fibers and articles from solutions of PEEK in non-sulfonating acid solvents in claimed. Solvents include methane sulfonic acid and trifluoromethane sulfonic acid. Sulfuric acid may be used as a diluent in non-sulfonating amounts. PEEK membranes are used as supports for composite ultrafiltration and reverse osmosis membranes. A method of making membranes, fibers, and articles is also described.

Abstract: A method of separating water of reduced concentration of a selected solute via reverse osmosis, wherein the selected solute is sulfuric acid, sodium hydroxide, isopropanol, sodium nitrate or another solute having a much higher solute passage than sodium chloride. The reverse osmosis membrane is prepared by treating a crosslinked, polyamide discriminating layer with an amine-reactive reagent or compatible oxidant at conditions whereby the passage of the selected solute at a selected transmembrane pressure is reduced by at least 30 percent.

Abstract: A reverse osmosis membrane having improved rejection of sulfuric acid and/or isopropanol is described. The membrane is prepared by treating a crosslinked, polyamide discriminating layer with a compatible oxidizing reagent, such as peracetic acid, periodic acid or chloramine, whereby the passage through the treated membrane of sulfuric acid in a 2 percent aqueous solution at a transmembrane pressure of 400 psi is reduced by at least 30 percent.

Abstract: A reverse osmosis membrane having improved rejection of sulfuric acid and/or isopropanol is described. The membrane is prepared by treating a crosslinked, polyamide discriminating layer with an amine-reactive reagent selected from a carboxylic acid ester, a carboxylic acid anhydride, an amine-reactive organic halogen compound, an ethylenically unsaturated hydrocarbon, or a 1,3-propane sultone, at conditions whereby the passage of sulfuric acid in a 2 percent aqueous solution at a transmembrane pressure of 400 psi is reduced by at least 30 percent.

Abstract: A novel hyperfiltration membrane and process for making the same is described. The membrane is useful for processing copper electroless solutions to concentrate for re-use salts of chelating agents. The membrane can be prepared by crosslinking a water-compatible polymer in the presence of a strong mineral acid, such as phosphoric acid.

Abstract: A novel hyperfiltration membrane and process for making the same is described. The membrane is useful for processing copper electroless solutions to concentrate for re-use salts of chelating agents. The membrane can be prepared by crosslinking a water-compatible polymer in the presence of a phosphorus-containing acid, such as phosphoric acid, wherein the acid is present in a sufficient amount to catalyze crosslinking and to form a plurality of pores in the coating when dried.

Abstract: A novel water softening membrane and process for making the same is described. The membrane can be prepared by treating a polyamide reverse osmosis membrane with a strong mineral acid followed by treatment with a rejection enhancing agent. The resulting membrane at transmembrane pressures of 50 psi can attain a magnesium sulfate rejection with a 0.2 percent aqueous solution of more than 90 percent with a water flux of more than 15 gallons per square foot per day.

Abstract: Good salt rejection and flux characteristics can be obtained with reverse osmosis membranes made from crosslinked, interfacially polymerized aromatic polyamides, particularly poly(arylenepolyamine aromaticpolycarboxylamides) such as poly(phenylenediamine trimesamide). The aromatic polyamides are preferably synthesized directly from an essentially monomeric polyacyl halide (at least tri- or higher in acyl functionality) and an essentially monomeric arylene polyamine with a measurable water solubility. As compared to closely analogous linear polymers, these interfacially polymerized, crosslinked polyamides have a lower % elongation and lower solubility (e.g. in amide solvents). Chlorine resistance characteristics of these polyamides are also good and can be improved by treatment with a chlorinating agent. In the preferred practice of the method for making a reverse osmosis membrane, a porous support layer is coated with the polyamine component (e.g.