Xenon recovery

Air separation industry, U.S., 27 754 Air-separation plants, 27 359, 750-751 Air-separation units, krypton and xenon recovery from, 2 7 362 Air-slaked lime, 15 26 Air slaking, 25 43 Air sparging... 

If, in addition, krypton, xenon or neon are produced, analytics will extend considerably (see Section 3.5). Due to the presently increasing size ofOj-produdng air separation units a krypton/xenon recovery is more and more of economical interest. Actually many Linde plants are equipped with such krypton/xenon-enrichment columns which are integrated in the main cold box and thus belonging to the main air separation unit. The enriched noble gas containing liquid is continuously directed to a tank and from there often shipped by road tank cars to a Kr/Xe-purification unit for further refurbishment... 

The latest of three ethylene recovery plants was started in 1991. Sasol sold almost 300,000 t of ethylene in 1992. Sasol also produces polypropylene at Secunda from propylene produced at Sasol Two. In 1992 Sasol started constmction of a linear alpha olefin plant at Secunda to be completed in 1994 (40). Initial production is expected to be 100,000 t/yr pentene and hexene. Sasol also has a project under constmction to extract and purify krypton and xenon from the air separation plants at Sasol Two. Other potential new products under consideration at Sasol are acrylonitrile, acetic acid, acetates, and alkylamines. 

Off-Gas Treatment. Before the advent of the shear, the gases released from the spent fuel were mixed with the entire dissolver off-gas flow. Newer shear designs contain the fission gases and provide the opportunity for more efficient treatment. The gaseous fission products krypton and xenon are chemically inert and are released into the off-gas system as soon as the fuel cladding is breached. Efficient recovery of these isotopes requires capture at the point of release, before dilution with large quantities of air. Two processes have been developed, a cryogenic distillation and a Freon absorption. 

Rapidity of recovery has been one of the most consistent and compelling features of anaesthesia with xenon. After 2 hours of xenon anaesthesia recovery is two to three times as fast as recovery from equi-MAC mixtures of N20/sevoflurane and N20/isoflurane. Marked emetic effects after both nitrous oxide and xenon were reported in a volunteer study, but this was conducted under highly artificial conditions. 

Accurate determination of the biological important element, selenium, in blood serum by isotope dilution analysis using ICP-QMS with octopole collision cell (Agilent 7500ce, Tokio, Japan) is described by Schaumloffel and coworkers.55 A recovery of selenium from human serum reference material was only 78 % when hydrogen was applied as collision gas but 96.7 % using xenon as a non-reactive collision gas to eliminate isobaric interferences. A detection limit of 3.3p,gl-1 was achieved.55... 

For volatile materials vapor phase chromatography (gas chromatography) permits equilibration between the gas phase and immobilized liquids at relatively high temperatures. Tire formation of volatile derivatives, e.g., methyl esters or trimethylsilyl derivatives of sugars, extends the usefulness of the method.103104 A method which makes use of neither a gas nor a liquid as the mobile phase is supercritical fluid chromatography.105 A gas above but close to its critical pressure and temperature serves as the solvent. The technique has advantages of high resolution, low temperatures, and ease of recovery of products. Carbon dioxide, N20, and xenon are suitable solvents. 

In addition, development studies have addressed the recovery of stable rhodium, xenon, technetium, and palladium because of their limited availability in nature. For palladium this would amount to about 40 kg per year from a 1000 MWe reactor. However, a... 

Interaction of XeFo with Some Other Protonic Acids. HCl.— Xenon difluoride did not interact with pure HCl (1 1) at —58 but addition of anhydrous HF produced a red-brown coloration at 100 . Xenon was evolved even at — lOO and quantitative recovery of the Xe was obtained at —50 . The interaction proceeded according to the equation... 

Krypton and Xenon are valuable gases present in very low concentrations in air. U.S. 6,662,593 assigned to Air Products describes a cryogenic distillation process for air separation with recovery of a stream concentrated in Kypton and Xenon. What would be the cost of producing purified Krypton and Xenon by this method Consider reactive methods for separating Krypton and Xenon from the concentrated stream as well as the methods suggested in the patent. 

Steinberg, M. The Recovery of Fission Product Xenon and Krypton by Absorption Processes, Report BNU542, 1959. 

Xenon is reported not to prolong the neuromuscular blocking effects of rocuronium.It is also reported to have less effect on recovery from vecuronium-induced neuromuscular block than sevoflurane. Xenon is also reported not to affect the onset time, duration and recovery from mi-vacurium. ... 

An estimate of the average xenon diffusion constant in PMP can be made from the coalescence of peaks if independent domain size information(S,77j is available. A domain size for the amorphous region can be determined by fitting the proton magnetization recovery curve shown in Figure 11. The equation describing the recovery of the magnetization(26j is... 

The cryogenic fractional distillation of large quantities of atmospheric air is the only practical means available for acquiring the rare gases krypton, neon, and xenon. The recovery of crude rare gases is accomplished in multiple cryogenic fractional distillation columns and... 

---