Abstract: A supported gas separation membrane for separating a particular component from a mixture of gases, a process for its manufacture and the use of the membrane in the separation of gases are provided in which the supported gas separation membrane comprises (a) a porous polymeric support layer and (b) an asymmetric gas separation membrane layer formed from a polyimide having repeating units of the general formula: ##STR1## wherein R is: ##STR2## and x is an integer.

Abstract: A novel filter element is constructed from expanded polytetrafluoroethylene (ePTFE) membrane possessing high strength which is sufficient to withstand filtration processing, as well as permitting the use of low energy to flex and clean the filter element. Further, the novel filter element of the present invention is non-linting and non-contaminating due to the ePTFE membrane structure of the filter, thereby providing excellent filtration performance for a variety of industries requiring high efficiency filtration.

Abstract: A selection device for delivering one of two gases to an apparatus includes an apparatus having an inlet and an outlet, and a gas delivery line connected to the inlet of the apparatus. A first feed line and a second feed line for respectively feeding a first and a second gas are provided. A first purge line and a second purge line are also provided, the first feed line being connected to the first purge line and the second feed line being connected to the second purge line. A common connection line connects the first and the second feed lines to the gas delivery line. An additional purge line is connected to the outlet of the apparatus. A first element, a second element, and a third element for creating a pressure drop are disposed in the first, the second, and the additional purge lines, respectively, the first element for creating a pressure drop and the third element for creating a pressure drop being flow-regulating elements, the second element for creating a pressure drop being a backpressure regulator.

Abstract: A device for removing at least laughing gas and anesthetic vapor from a gas sample based on a molecular sieve shall be improved such that it possesses good adsorption properties for both gas components. A molecular sieve arrangement is provided, which is flown through from a gas inlet to a gas outlet and comprises a first molecular sieve area with a first pore size between about 0.3 nm and 0.5 nm and a second molecular sieve area with a second pore size between about 0.8 nm and 1 nm.

Abstract: In one aspect, a method for selectively removing at least one target component from a multicomponent feed fluid using a removal system, the system including a feed chamber having an inlet and an outlet, a permeate chamber, and a membrane for separating the feed and permeate chambers. The membrane is selective for the at least one target component.

Abstract: A method for separating gases or other fluids involves placing a magnetic field on a monolithic carbon fiber composite sorption material to more preferentially attract certain gases or other fluids to the sorption material to which a magnetic field is applied. This technique may be combined with the known "pressure swing adsorption" technique utilizing the same sorption material.

Abstract: A process for the separation of a gas mixture containing oxygen and nitrogen, including bringing the mixture into contact in an adsorption zone with a first selective adsorbent for nitrogen of faujasite type exchanged to at least 80% with lithium, in which the Si/Al ratio is lower than 1.5 and a second selective adsorbent for nitrogen of zeolite type exchanged with divalent cations such as the alkaline-earth metal or transition metal cations. The second adsorbent is characterized by a nitrogen adsorptivity C.sub.2 lower than the nitrogen adsorptivity C.sub.1 characterizing the first adsorbent, and an adsorption selectivity for nitrogen in relation to oxygen (1.times.10.sup.5 Pa, 20.degree. C.) higher than or equal to 3.

Abstract: An HVAC filter having a pleated paper filter and a plastic pre-filter, the filter and pre-filter are mounted in a parallel relation in the frame. The plastic pre-filter includes a plastic mesh having a plurality of openings, and an irregular surface on the inlet side to prevent matting of filtered material.

Abstract: A method and apparatus for preventing contamination of a substrate or a substrate surface, and particularly relates to prevention of contamination of raw materials, semi-finished products, base materials of products and substrate surface in a high-tech industry such as in the production of semiconductors and liquid crystals. A gas coming into contact with a base material or substrate is purified by dust removing apparatus and adsorption and/or absorption apparatus so that the concentration of fine particles in the gas is below class 1,000 and a non-methane hydrocarbon concentration is below 0.2 ppm. Thereafter, the base material or the substrate surface is exposed to this gas.

Abstract: An apparatus and process for the continuous, near real-time monitoring of low-level concentrations of organic compounds in a liquid, and, more particularly, a water stream. A small liquid volume of flow from a liquid process stream containing organic compounds is diverted by an automated process to a heated vaporization capillary where the liquid volume is vaporized to a gas that flows to an automated gas chromatograph separation column to chromatographically separate the organic compounds. Organic compounds are detected and the information transmitted to a control system for use in process control. Concentrations of organic compounds less than one part per million are detected in less than one minute.

Abstract: This invention provides a polyamide separation membrane, prepared from high molecular weight polyamide having a repeating unit represented by the formula (I) and a process for separating gaseous mixtures using them. ##STR1## wherein, R is an aliphatic or aromatic organic group derived from dicarboxylic acid or halide. The polyamide separation membrane according to the present invention has a large free volume and good permeation properties such as permeability and permeation selectivity.

Abstract: Processes and systems to recover at least one perfluorocompound gas from a gas mixture are provided. In one embodiment the inventive process comprises the steps of a) providing a gas mixture comprising at least one perfluorocompound gas and at least one carrier gas, the gas mixture being at a predetermined pressure; b) providing at least one glassy polymer membrane having a feed side and a permeate side; c) contacting the feed side of the at least one membrane with the gas mixture; d) withdrawing from the feed side of the membrane as a non-permeate stream at a pressure which is substantially equal to the predetermined pressure a concentrated gas mixture comprising essentially the at least one perfluorocompound gas; and e) withdrawing from the permeate side of the membrane as a permeate stream a depleted gas mixture comprising essentially the at least one carrier gas.

Abstract: A process for removing nitrogen oxides, as well as water and carbon dioxide, from gas streams containing at least 0.2 ppm by volume of nitrogen oxides by passing the gas stream through an alumina adsorbent and a zeolite adsorbent, preferably 13X-zeolite. The process has utility in front end cleanup of air prior to cryogenic distillation of the air where nitrogen oxides would otherwise freeze under the cryogenic processing.

Abstract: An apparatus, for storage and dispensing of a sorbable fluid, including a storage and dispensing vessel containing a solid-phase physical sorbent medium for holding a sorbable fluid, with heat transfer means being associated with the vessel for thermally managing heat effects due to adsorption and desorption of the sorbable fluid.

Abstract: An air dryer and reservoir assembly for providing compressed air from an air compressor (20) on a heavy motor vehicle which includes an air dryer (14) connected to receive compressed air from the air compressor (20) and a secondary reservoir (12) for storing compressed air which passes through the air dryer (14), with the air dryer (14) and the secondary reservoir (12) being securely attached to a housing (16) to form an air dryer reservoir module (10). A primary reservoir (18) for storing compressed air from the air dryer (14) is located remote from the air dryer reservoir module (10). Components located within the housing (16) control air flow between the air dryer (14) and the primary and secondary reservoirs (18,12) and also monitor the pneumatic brake system circuits fed by the primary and secondary reservoirs (18,12). In the event of a failure of either of the pneumatic brake system circuits speed of the vehicle is limited.

Abstract: An inline ultra-high efficiency filter comprising a housing having a chamber extending the length thereof, an inlet and an outlet providing flow passages into and from the chamber. Seated in the chamber is a porous sintered metal filter element having a tubular body open at its end adjacent the inlet and an end wall at its other end adjacent the outlet, and the filter element provides an internal flow passage extending therein from the inlet to the end wall. A sealing weldment provides an air tight seal between the periphery of the filter element and the housing adjacent the inlet. The filter element is spaced from the wall of the chamber to provide a plenum space thereabout, and a gas stream entering the inlet end of the filter passes into the internal flow passage of the filter element and outwardly of the body of the filter element into the plenum space and thence outwardly of the outlet end of the filter.

Abstract: An acoustic oxygen sensor is provided which can be used in the output lines leading from the sieve beds. This sensor can be used in communication with a microprocessor to control the production and evacuation cycles of the sieve beds, i.e., for example to determine the period for which a bed is supplied with compressed air and communicates with the reservoir as well as to determine the pressure of the compressed air and to determine the amount of time that the product gas is fed through the flow equalization path to supply an aliquot of purging gas to a used bed. In the feedback loop, the microprocessor utilizes the measured oxygen concentration and flow rate to optimize the settings necessary to achieve maximum oxygen concentration and flow rate efficiency. Since the microprocessor has the ability to make incremental changes and compare relative values, the optimum values can be determined empirically eliminating the need to perform complex theoretical calculations.

Abstract: A pressure swing adsorption process for absorbing CO.sub.2 from a gaseous mixture containing CO.sub.2 comprising introducing the gaseous mixture at a first pressure into a reactor containing a modified alumina adsorbent maintained at a temperature ranging from 100.degree. C. and 500.degree. C. to adsorb CO.sub.2 to provide a CO.sub.2 laden alumina adsorbent and a CO.sub.2 depleted gaseous mixture and contacting the CO.sub.2 laden adsorbent with a weakly adsorbing purge fluid at a second pressure which is lower than the first pressure to desorb CO.sub.2 from the CO.sub.2 laden alumina adsorbent. The modified alumina adsorbent which is formed by depositing a solution having a pH of 3.0 or more onto alumina and heating the alumina to a temperature ranging from 100.degree. C. and 600.degree. C., is not degraded by high concentrations of water under process operating conditions.

Abstract: An air prepurification process which includes, as a first step, a pressure swing adsorption process in which the air is passed through a bed of adsorbent which contains activated alumina, thereby effecting removal of substantially all moisture and most carbon dioxide from the feed air and as a second step, a temperature swing adsorption process in which the dried feed air is passed through a bed of carbon dioxide-selective adsorbent, thereby removing substantially all of the carbon dioxide remaining in the feed air. The feed air may be passed through beds of hydrogen oxidation and carbon monoxide oxidation catalysts between the first and second steps to convert any hydrogen and carbon monoxide in the feed air to water vapor and carbon dioxide, respectively, these components being removed from the feed air during the second step.

Abstract: A high-porosity metallic membrane element comprising a sintered element having at least about 55% porosity, the sintered element comprising a matrix of substantially interconnected pores, each of the pores being defined by a plurality of dendtritic metallic particles. A preferred form is made from pure nickel, preferably filamentous nickel powder. The high-porosity metallic membrane element, comprising the aforementioned sintered element having at least about 55% porosity, can be sealed within a filter housing to produce a highly porous filter device with a filtered fluid flow path through the metal membrane element. Also disclosed is a method of making the high-porosity metallic membrane element which includes depositing by air-laying techniques a substantially uniform low-density bed of a sinterable dendritic material into a mold suitable for applying compressive force thereto, compressing the low-density bed of sinterable dendritic material to form a green form, and sintering the green form.