An adsorption process for xenon recovery from a cryogenic liquid or gas stream is described wherein a bed of adsorbent is contacted with the aforementioned xenon containing liquid or gas stream and adsorbs the xenon selectively from this fluid stream. The adsorption bed is operated to at least near full breakthrough with xenon to enable a deep rejection of other stream components, prior to regeneration using the temperature swing method. Operating the adsorption bed to near full breakthrough with xenon, prior to regeneration, enables production of a high purity product from the adsorption bed and further enables oxygen to be used safely as a purge gas, even in cases where hydrocarbons are co-present in the feed stream.

In a process for alkylating an aromatic hydrocarbon feedstock with an olefin feedstock, at least one of the aromatic hydrocarbon and olefin feedstocks is passed through a pretreatment unit containing an adsorbent such that the adsorbent removes impurities contained by the feedstock. Passage of the at least one feedstock through the pretreatment unit is then terminated and a heated inert gas is passed through the pretreatment unit such that the inert gas desorbs impurities from the adsorbent to produce an inert gas effluent stream containing the desorbed impurities. A condensable fluid is added to at least part of the inert gas effluent stream such that at least a portion of the impurities contained therein condense with said fluid to leave a purified inert gas stream, which is recycled to the pretreatment unit.

Na.sup.+-SAPO-34 sorbents were ion-exchanged with several individual metal cations for CO.sub.2 absorption at different temperatures (273-348 K) and pressures (<1 atm). In general, the overall adsorption performance of the exchanged materials increased as follows: Ce.sup.3+<Ti.sup.3+<Mg.sup.2+<Ca.sup.2+<Ag.sup.+<Na.sup.+<Sr.sup.2+. The strontium exchanged materials excelled at low-pressure ranges, exhibiting very sharp isotherms slopes at all temperatures. The Sr.sup.2+ species were responsible for the surface strong interaction and the cations were occupying exposed sites (SII) in the materials Chabazite cages. All the sorbent materials exhibited higher affinity for CO.sub.2 over the other gases tested (i.e., CH.sub.4, H.sub.2, N.sub.2 and O.sub.2) due to strong ion-quadrupole interactions. Sr.sup.2+-SAPO-34 sorbents are by far the best option for CO.sub.2 removal from CH.sub.4 mixtures, especially at low concentrations.

A mineral polymer for reducing pollutants, in particular for gas absorbing, absorbing pollutant volatile organic compounds such as volatile organic hydrocarbons and/or capturing particulate pollutants. The mineral polymer may be a metakaolin-based mineral polymer with a porous or non-porous structure. The use of the mineral polymer for reducing pollutants includes for absorbing one or more pollutant gases, such as NOx (such as NO.sub.2), SOx (such as SO.sub.2) and/or CO.sub.2, for absorbing pollutant volatile organic compounds such as volatile organic hydrocarbons and/or for capturing particulate pollutants, such as those produced by diesel engines. The pollutants are removed directly from the engine exhaust, from a ventilation system, or at the road side. A method for reducing pollutants comprises the steps: (i) providing the mineral polymer; (ii) exposing said mineral polymer to one or more pollutants; and optionally, (iii) regenerating the capability of the mineral polymer to reduce pollutants. Regeneration may be carried out by washing with a solvent, or heating. The solvent may be water or another suitable solvent.

As an improvement to processes for desulfurization of natural gas and synthetic natural gas streams that employ conventional zeolitic materials (absorbents), including copper-containing zeolites, pre-treatment methods and post-treatment methods are provided that lower the level of leachable benzene following desulfurization with the absorbents to <0.5 mg benzene/L leachate, while retaining within the absorbents a majority of sulfur adsorbed from a gas stream.

Disclosed herein are novel RHO zeolites useful as kinetically selective adsorbents for oxygen and/or nitrogen. The adsorbents can be used in pressure swing adsorption processes for selectively adsorbing oxygen and/or nitrogen from feed streams such as an air stream or crude argon stream. Also disclosed are novel methods of preparing RHO zeolites, including in particular mixed-cation RHO zeolites.

The present invention relates in a first aspect to a method for producing in the interior of a production equipment a dehydrated liquid mixture for use as a solvent for a conducting salt (e.g. LiPF.sub.6) wherein after cleaning the equipment with isopropyl alcohol and providing or preparing a liquid starting mixture in said interior of the production equipment both the isopropyl alcohol content in the mixture and the water content in the mixture is reduced by interaction with a zeolite molecular sieve.

A process for regenerating an adsorbent for nitrogen-containing compounds present in a hydrocarbon feed comprising contacting the adsorbent with an inert gas at a temperature in the range of from 10 to 60 C., followed by contacting the adsorbent with an inert gas at an elevated temperature in the range of from 200 to 260 C. and cooling the adsorbent in an inert gas.

A dishwasher is provided that has a washing container an air-guiding channel to generate an air flow; a sorption drying system to dry items to be washed, wherein the sorption drying system has a sorption container with reversibly dehydratable sorption material, and wherein the sorption container is connected to the washing container by the air-guiding channel. A heater is assigned to the sorption material for desorption of the sorption material, and a ratio of the heat output of the heater and the air volume flow of the air flow which flows through the sorption material is between 100 W sec/l and 1250 W sec/l.

A system is disclosed in which water-saturated desiccant in a dehydration unit, having previously been used to dehydrate natural gas, is regenerated in a closed loop process using liquid petroleum gas (LPG). LPG is pumped from a storage tank, vaporized and superheated. The superheated LPG gas enters the dehydration unit such that the hot gas passes over the desiccant thereby regenerating the desiccant. An overhead stream from the dehydration unit passes to a condenser where the temperature of the hot gas from the dehydration unit is dropped to form a fluid stream containing LPG, water and non-condensable gases. The fluid stream passes to a three phase separator for separating the fluid stream into a gas stream, a water stream, and a liquid stream containing LPG which is then returned to the storage tank for reuse in the closed loop process.