Disclosed is a mass selective fluid bandpass filter. This filter provides for selecting gas molecules of a specific mass from a gas sample containing molecules of two or more mass species. This provides for a low power, low cost apparatus for producing .sup.3He from terrestrial sources of helium gas by selective enrichment. This invention further discloses a portable, field deployable means of .sup.3He/.sup.4He ratio determination employing one or more of the effects consisting of: statistical linear regression plots of heat ramps, variable emission currents within a quadruple mass spectrometer, use of a quadrupole mass spectrometer in concert with ultrahigh vacuum maintained by non-evaporable getter pumps, and/or construction of vacuum housing structures from non-steel or non-stainless steel alloys, and or non metallic materials selected from a group consisting of: aluminum, titanium, ceramics, or glass. This provides a compact, sensitive field deployable unit with low power consumption.

A process for separating components or a fluid mixture using membranes comprising a selective layer made from copolymers of an amorphous per fluorinated dioxolane and a fluorovinyl monomer. The resulting membranes have superior selectivity performance for certain fluid components of interest while maintaining fast permeance compared to membranes prepared using conventional perfluoropolymers, such as Teflon? AF, Hyflon? AD, and Cytop?.

Recovering xenon and/or krypton from a feed gas can include utilization of a purge stream from a separation column positioned and configured to output at least one stream of fluid that is substantially nitrogen and at least one stream of fluid that is substantially oxygen. The purge stream can be split so that a first portion of the purge stream is fed as a liquid adjacent to a top of a purge treatment column and a second portion of the purge stream can be fed to a heat exchanger for superheating the second portion to feed a superheated vapor at or adjacent to a bottom of the purge treatment column. The purge treatment column can output a liquid stream that has a relatively high concentration of Xe and/or Kr therein as a feed stream for an Xe and/or Kr recovery system.

A plant for producing an argon-rich stream from a mixture formed by a purge fluid from a plant for producing ammonia comprises at least two methane scrubbing columns upstream of a methane separation column and, downstream therefrom, a nitrogen/argon separation column.

A method for processing powdered starting materials includes a powdered material created and packaged under a protective gas atmosphere such that a protective gas is also present in the package, and the packaged powdered material is unpacked by a user and sent for further processing, wherein a gas detectable with sensors is supplied to the protective gas during packaging and/or in the packaging, or the protective gas is a gas that can be detected with sensors and the manufacturer and packager of the powdered material and/or the end user will examine the package with sensors to detect an escape of the detectable gas.

A method and system for collecting xenon (Xe) is described. A microchannel heat exchanger is used in combination with a mechanical cooler and an absorbent. A combination of components makes up a Xe Collection Subsystem that is adapted for use in an efficient process for collecting, purifying, and measuring Xe isotopes collected from air as part of the International Monitoring System.

A method is provided for refining an argon gas, in which oxygen is added to the argon gas containing hydrogen, carbon monoxide(CO), and oxygen as impurities so that the hydrogen and the CO are converted into water and carbon dioxide in a catalyst tower, or hydrogen is added to the argon gas so that the oxygen is converted into the water; the method including: monitoring the hydrogen, the CO, and the oxygen on an outlet side of the catalyst tower; and at least one of adding the oxygen to the argon gas when any one of the hydrogen and the CO is detected on the outlet side of the catalyst tower, and adding the hydrogen when the oxygen is detected, wherein the oxygen or the hydrogen to be added is intermittently added to the catalyst tower relative to continuous supply of the argon gas to the catalyst tower.

A method for extending useful life of a sorbent for purifying a gas by sorption of an impurity is provided. The method generating a electrical discharge within the gas to obtain a spectral emission representative of a concentration of the impurity. The method also includes monitoring the concentration of the impurity according to the spectral emission. The method also includes lowering the concentration of the impurity by conversion of at least a portion of the impurity into a secondary impurity having a greater affinity to the sorbent than the impurity. The method also includes comparing the concentration of the impurity to a polluting concentration and managing the sorption of the gas onto the sorbent according to the comparison.

This invention discloses a membrane composition, a method of making, and applications for a new type of high selectivity, high plasticization-resistant and solvent-resistant, both chemically and UV cross-linked polyimide membranes. Gas permeation tests on these membranes demonstrated that they not only showed high selectivities, but also showed extremely high CO.sub.2 plasticization resistance under CO.sub.2 pressure up to 4923 kPa (700 psig). This new type of high selectivity, high plasticization-resistant and solvent-resistant, both chemically and UV cross-linked polyimide membranes can be used for a wide range of gas separations such as separations of H.sub.2/CH.sub.4, He/CH.sub.4, CO.sub.2/CH.sub.4, CO.sub.2/N.sub.2, olefin/paraffin separations (e.g. propylene/propane separation), O.sub.2/N.sub.2, iso/normal paraffins, polar molecules such as H.sub.2O, H.sub.2S, and NH.sub.3 mixtures with CH.sub.4, N.sub.2, H.sub.2, and other light gases separations. The membranes can also be used for liquid separations such as in the removal of organic compounds from water.

An isotope production system, emanation generator, and process are disclosed for production of high-purity radioisotopes. In one implementation example, high-purity Pb-212 and/or Bi-212 isotopes are produced suitable for therapeutic applications. In one embodiment the process includes transporting gaseous radon-220 from a radium-224 bearing generator which provides gas-phase separation of the Rn-220 from the Ra-224 in the generator. Subsequent decay of the captured Rn-220 accumulates high-purity Pb-212 and/or Bi-212 isotopes suitable for direct therapeutic applications. Other high-purity product isotopes may also be prepared.