Abstract: Water-free membranes suitable for separating aliphatically-unsaturated hydrocarbons from saturated hydrocarbons are disclosed wherein the membranes are comprised of preformed membranes of polymeric materials capable of chemically binding positive ions and the membranes have been ion exchanged to contain metal ions as well as being plasticized with polyhydric alcohols. The water-free membranes provide for facilitated transport of aliphatically-unsaturated hydrocarbons through a membrane process wherein the unsaturated species of the feed mixture is transported across the plasticized membrane by virtue of the metal ions interacting selectively and reversibly with the unsaturated species. The separation of ethylene from ethane utilizing the water-free membrane system is of particular interest.

Abstract: A fluid distribution system for a fluid separation module having a bundle of hollow fiber membranes positioned in a cylindrical shell and extending through a tube sheet positioned in an enlarged end portion of the shell, the enlarged end portion of the shell having therein an inlet opening for a fluid mixture, wherein a first sleeve attached to the tube sheet and surrounding the bundle of fibers extends into a second sleeve spaced from the tube sheet and having a larger diameter than the first sleeve such that a fluid mixture entering the inlet opening flows radially between the tube sheet and the second sleeve and then axially between the first and second sleeve. A third sleeve is spaced from the first sleeve to provide a path therebetween for the axially flowing fluid mixture to enter the bundle of fibers at an oblique angle and in a direction away from the tube sheet.

Abstract: A fluid distribution system for a fluid separation module having a bundle of hollow fiber membranes positioned in a cylindrical shell and extending through a tube sheet positioned in an enlarged end portion of the shell, the enlarged end portion of the shell having therein an inlet opening for a fluid mixture, wherein a first sleeve attached to the tube sheet and surrounding the bundle of fibers extends into a second sleeve spaced from the tube sheet and having a larger diameter than the first sleeve such that a fluid mixture entering the inlet opening flows radially between the tube sheet and the second sleeve and then axially between the first and second sleeve. A third sleeve is spaced from the first sleeve to provide a path therebetween for the axially flowing fluid mixture to enter the bundle of fibers at an oblique angle and in a direction away from the tube sheet.

Abstract: A process for severing a polymeric tube sheet to expose bores of the hollow fibers embedded in the tube sheet wherein the tube sheet is provided with a circumferential stress raiser and compressive forces are applied to the tube sheet to fracture off a portion of the tube sheet at the stress raiser to expose the bores of the hollow fibers embedded therein.

Abstract: A fluid separation module to be mounted in a cylindrical shell and the method of mounting the same, the module including a bundle of hollow fiber membranes and a polymeric tube sheet, the tube sheet being positioned at one end of the bundle of hollow fiber membranes with the hollow fiber membranes extending through the tube sheet. A resilient sheet having the form of the slit tube surrounds the bundle of hollow fibers and is held in this configuration by a plurality of rings encircling the slit tube at spaced intervals thereon, the slit tube being secured to the tube sheet. The rings are slideably mounted on the slit tube in such a manner that, as the module is inserted in the shell, the rings can be manually slid to one end of the slit tube to allow the slit tube to expand into contact with the inner surface of the tubular shell and thereby allow the fiber bundle to open for improved flow of the fluid mixture through the bundle.

Abstract: A process for treating a landfill for recovering methane therefrom wherein a mixture of methane and carbon dioxide is withdrawn from a central portion of the landfill and the carbon dioxide and methane are separated. The methane is fed to a pipeline and a portion of the carbon dioxide is fed to wells spaced around the periphery of the landfill at a pressure of 7 to 170 kPa to prevent air from entering the landfill around the periphery thereof.

Abstract: A process for severing a tube sheet made from a polymeric material to expose bores of hollow fibers having the ends thereof embedded in the tube sheet, with the tube sheet having a cylindrical configuration and a stress raiser extending around the periphery thereof, wherein a ring having a lower coefficient of expansion than the material of the tube sheet is positioned to encircle the tube sheet at a location adjacent to the stress raiser. The tube sheet is then heated to expand it to the point where stress causes the tube sheet to fracture off that portion of the tube sheet encircled by the ring from the remainder of the tube sheet to expose bores of the fibers.

Abstract: A modular spinnerette assembly for forming hollow fibers wherein a spinnerette plate having a central bore is positioned in stacked alignment with a cylindrical member having an enlarged central opening and an annular plate, with a tube extending radially through one side of the annular plate and terminating in the bore in the spinnerette plate for cooperating with this bore to form a hollow fiber when a spinning solution is passed through the apparatus. The assembly is provided with means for centering the tube in the central bore in the spinnerette plate.

Abstract: A multicomponent membrane having improved permeation characteristics for separation of one gas from a mixture of gases by permeation of the one gas through the membrane. The membrane is in the form of a porous, anisotropic substrate membrane and a coating in contact with the substrate membrane, the coating being made of poly(dimethyl siloxane), containing 1 to 20 weight percent of a permeation-modifying radical selected from the group consisting of ##STR1## The coating is applied to the substrate in the form of a solution of 0.05 to 1 weight percent of the coating in a suitable solvent such as pentane.

Abstract: Process for recovering a permeating gas from a pair of gas streams one of which contains less than 30 percent of the permeating gas and the other of which contains more than 70 percent of the permeating gas wherein the other gas stream is brought into contact with a membrane through which a portion of the permeating gas passes. Non-permeating gases are mixed with the one stream and brought into contact with another membrane through which the permeating gas will pass, with the permeating gases from the membrane being combined and collected.