Abstract: A mixed gas consisting of carbon dioxide and nitrogen is separated into the component gases by a method which comprises treating sepiolite with nitric acid, subjecting the treated sepiolite to an ion-exchange treatment thereby exchanging the cationic metal present in the treated sepiolite with Mg ions, heating the sepiolite resulting from the ion-exchange treatment, and exposing the ultimately prepared sepiolite to the mixed gas.

Abstract: The process of purifying oxygen-containing exhaust gases produced by combustion of waste materials including garbage, industrial waste and sewage sludge includes reacting an exhaust gas containing pollutants in a gas-solids suspension at a temperature of 120.degree. to 140.degree. C. and at a gas velocity from 3 to 20 m/s for a reaction time of 0.5 to 10 seconds with a mixture containing naturally occurring zeolites to remove mercury, mercury compounds and polyhalogenated hydrocarbons pollutants from the exhaust gas. The naturally occurring zeolites have a median particle size (d.sub.50) from 5 to 50 micrometers and the gas-solids suspension has a mean suspension density from 0.020 to 10 kg of solids per sm.sup.3 of exhaust gas. The mixture contains from 10 to 20% by weight mordenite, from 60 to 70% by weight clinoptilolite, from 0 to 5% by weight montmorillonite and a remaining balance of SiO.sub.2. The purified gas contains <50 micrograms of mercury per sm.sup.3, <0.1 ng TE per sm.sup.

Abstract: PSA process for the separation of nitrogen from a gaseous mixture containing nitrogen by selective adsorption of nitrogen from the gaseous mixture in an adsorbent mass with cyclic pressure variations. At least one nitrogen adsorption phase is carried out at high pressure and at least one nitrogen desorption phase is carried out at low pressure. The adsorbent mass is arranged in a rotating adsorber and at least 50% of the adsorbent mass is constituted by a zeolite exchanged with lithium by more than 50%.

Abstract: An improved process for the oxygen enrichment of air by vacuum swing adsorption, pressure swing adsorption or a combination thereof, wherein the improvement comprises providing at least one packing at each of the air inlet to and air outlet from the adsorber, the packing at the air inlet side of the adsorber comprising Na-Ca zeolite X with an SiO.sub.2 /Al.sub.2 O.sub.3 ratio of 2.0 to 2.5 and with a CaO/Al.sub.2 O.sub.3 ratio of 0.4 to 0.75, the ratio being dependent upon the air inlet temperature, at an air inlet temperature of 20.degree. to 30.degree. C., the CaO/Al.sub.2 O.sub.3 ratio of the Na-Ca zeolite X at the inlet zone being 0.4 to 0.6, at an air inlet temperature of 30.degree. to 40.degree. C., the CaO/Al.sub.2 O.sub.3 ratio of the Ca zeolite X at the inlet zone being 0.55 to 0.65 and at an air inlet temperature of 40.degree. to 50.degree. C., the CaO/Al.sub.2 O.sub.3 ratio of the Na-Ca zeolite X at the inlet zone being 0.6 to 0.

Abstract: Separation of nitrogen and carbon dioxide is accomplished by a method using as a separating material one member selected from the group consisting of sepiolite in the unmodified form, sepiolite which has been heat-treated, and sepiolite which has had part or the whole of the exchangeable cation thereof replaced with zinc ion and which has been subsequently subjected to a heat treatment.

Abstract: A process and apparatus for the recovery and purification of a contaminated refrigerant withdrawn from a refrigeration or refrigerant recovery system which employs a compressor and an adsorbent selective for the adsorption of halogenated hydrocarbons. The adsorbent is selected from the group consisting of silicalite, faujasites, steamed and rare earth exchanged zeolite Y, mordenite, ZSM-5 and mixtures thereof, and more particularly the group consisting of a low cerium rare earth exchanged zeolite Y-84, a low cerium rare earth exchanged zeolite LZ-210, Breck Structure Six, ECR-32, and mixtures thereof. A significant increase in the capacity of these adsorbents over conventional adsorbents combined with the use of novel process steps to recover, purify and return a purified refrigerant to the refrigeration system result in significant cost savings at reduced risk of release of halogenated hydrocarbons to the environment.

Abstract: Chabazite, offretite, erionite, levyne, mordenite, gmelinite, zeolite A, zeolite T, EMC-2, ZSM-3, ZSM-18, ZK-5, zeolite L, and beta zeolite whose exchangeable cations are composed of 95 to 50% lithium ions, 4 to 50% of one or more of aluminum, cerium, lanthanum and mixed lanthanides and 0 to 15% of other ions are prepared by ion-exchanging the base zeolite with water-soluble trivalent ion salts and with water soluble lithium salts. The zeolites preferentially adsorb nitrogen from gas mixtures.

Abstract: It is now possible to desulfurize gases containing appreciable carbon dioxide proportions by limiting the production of carbon oxysulfide to a very low level, by treating these gases with adsorbents composed of very small, partially calcic zeolite A crystals agglomerated by clays containing low levels of iron and having reduced acidity and basicity. These clays may be obtained by phosphatization of montmorillonite, bentonite, attapulgite, or kaolin.

Abstract: Coatings and sensors having both steric and chemical selectivity. Controlled porosity provides the steric selectivity, whereas chemically tailored film properties, using controlled composition or modification by coupling agents, chemical species replacement, or chemical species within pores, provide the chemical selectivity. Single or multiple layers may be provided.

Abstract: Carbon dioxide is removed from a gas stream by passing the gas stream through a bed of natural or synthetic clinoptilolite or their chemically-modified derivatives. The process is particularly advantageous when applied to the removal of ppm levels of carbon dioxide from gas streams at temperatures above 20.degree. C.

Abstract: The present invention is a composition, a synthesis of the composition and a method of using the composition for selectively adsorptively separating nitrogen from oxygen wherein the composition is a crystalline EMT with a Si/Al ratio less than 2.0 and a micropore volume determined in the sodium and/or potassium form of at least 0.20 cm.sup.3 /g and a lithium cation exchange of at least 80%, preferably including an intergrowth with a crystalline FAU structure, wherein the pure or intergrowth compositions have the chemical formula:M.sub.2/n O:X.sub.2 O.sub.3 :(2.0 to <4.0)SiO.sub.2wherein M=one or more metal cations having a valence of n, and X is selected from the group consisting of aluminum, gallium and boron, preferably aluminum.

Abstract: Novel membranes comprise crystals of a zeo-type material carried by a porous support. The crystal growth of the zeo-type material is essentially continuous over the pores of the support and the zeo-type material is crystallized directly from and bonds directly to the support. Membranes may be prepared by immersing the support in a synthesis gel, crystallizing the gel, removing the support, and repeating these steps at least once.

Abstract: A porous filter having a pore size of no more than 80 .mu.m is provided in a refrigerant flow passage of a refrigeration system. The filter may be provided in a drier provided in the refrigerant flow passage or in a separate filter casing provided in the refrigerant flow passage. Alternatively, the filter may be provided in the refrigerant flow passage within a sealed casing of a refrigerant compressor which is incorporated in the refrigeration system. The filter is formed of a molded solid material constituted by alumina, silica gel, calcium sulfide and aluminosilicate.

Abstract: The present invention is a composition, a synthesis of the composition and a method of using the composition for selectively adsorptively separating nitrogen from oxygen wherein the composition is a crystalline EMT with a Si/Al ratio less than 2.0 and a lithium cation exchange of at least 80%, preferably including an intergrowth with a crystalline FAU structure, wherein the pure or intergrowth compositions have the chemical formula:(0.2-0.0)M.sub.2/n 0:(0.80-1.0)Li.sub.2 0:X.sub.2 0.sub.3 :(2.0 to <4.0)SiO.sub.2wherein M=a metal cation other than lithium having a valence of n, and X is selected from the group consisting of aluminum, gallium and boron, preferably aluminum.

Abstract: Pressure swing adsorption of air and other gas separation operations are carried out using specific preferred zeolite adsorbent compositions based on the symmetry of the framework atoms and cations therein. Specific SiO.sub.2 /Al.sub.2 O.sub.3 and cation/cation ratios for enhanced performance are identified. LiX adsorbent having a silica to alumina ratio on the order of 2.364 provides enhanced PSA performance.

Abstract: Carbon dioxide is removed from gas streams comprised predominantly of gases that are less polar than carbon dioxide by passing the gas stream through a bed of type X zeolite having a silicon to aluminum atomic ratio not greater than about 1.15, thereby adsorbing the carbon dioxide from the gas stream. The process is particularly advantageous when applied to the removal of low levels of carbon dioxide from gas streams at temperatures above 20.degree. C.

Abstract: 16-membered macrolide derivatives represented by the formula (I): ##STR1## wherein R.sup.1 represents a hydrogen atom or a COR.sup.6 group, wherein R.sup.6 represents a straight-chain alkyl group having 1 to 3 carbon atoms; R.sup.2 represents a hydrogen atom or a COR.sup.6 group, wherein R.sup.6 is as defined above; R.sup.3 represents a hydrogen atom or a COR.sup.6 group, wherein R.sup.6 is as defined above; R.sup.4 represents a straight-chain alkyl group having 1 to 4 carbon atoms or a substituted or unsubstituted allyl group; and R.sup.5 represents a substituted or unsubstituted, straight-chain or branched alkyl, alkenyl or aralkyl group having 1 to 10 carbon atoms;and pharmaceutically acceptable salts thereof are disclosed. These compounds show excellent and long-acting antimicrobial activities. A novel process for producing these 16-membered macrolide derivatives is further disclosed.

Abstract: A process is provided for the removal and recovery of chlorine from a chlorine plant offgas stream. A pressure swing adsorption (PSA) process is used to remove from the chlorine plant offgas a vent gas stream comprising hydrogen and a tail gas stream comprising chlorine which is subsequently liquefied. The PSA zone comprises at least 2 adsorption beds, wherein each of the adsorption beds contains a weak adsorbent selective for the adsorption of chlorine and the PSA process is operated with a short cycle having an adsorption time of less than about 6 minutes. The vent gas withdrawn from the process is essentially free of chlorine and a liquefied chlorine product is recovered. The process provides an economic and efficient way of removing chlorine from a chlorine plant offgas stream without requiring a vacuum pump or heat removal equipment.

Abstract: A process is disclosed for preparing a carbon molecular sieve used for the separation of oxygen from nitrogen, which comprises the steps of:(a) milling hard coal to a grain size of 95%<20.mu.m;(b) oxidizing the finely milled hard coal with air in a fluidized bed;(c) adding water and coal tar pitch as a binder and molding the finely milled hard coal into shape;(d) carbonizing the finely milled hard coal molded into shape in a rotary kiln at a temperature of 500 .degree.to 850.degree. C., with a dwelling time of 55 to 65 minutes, in order to obtain a carbonization product with a bulk density of 530 to 560 g/l;(e) activating the carbonization product with steam at to 900.degree. C. for 165 to 195 minutes to obtain a sintered carbonaceous product having a bulk density of 590 to 650 g/l; and(f) treating the sintered carbonaceous product at 750 to 850.degree. C. with carbon-splitting hydrocarbons to obtain said carbon molecular sieve.

Abstract: A process is described by which a chemical species is sorbed into the channels of a host phase which is then heated to affect an irreversible phase transformation of the host phase which seals the chemical species within its crystal structure. The host phase is an insoluble solid, non-toxic and stable both to the chemical species it encases and its environment.

Abstract: Type X zeolites whose charge-compensating cations are composed of 95 to 50% lithium ions, 4 to 50% of one or more of aluminum, cerium, lanthanum and mixed lanthanides and 0 to 15% of other ions. The zeolites preferentially adsorb nitrogen from gas mixtures.

Abstract: A process for impregnating zeolite with a quaternary ammonium cation (QAC) and then coating the impregnated zeolite with permanganate (such as potassium permanganate), and for impregnating zeolite with permanganate and then coating the impregnated zeolite with a QAC, and coated, impregnated zeolite crystals resulting from either process. Either coating acts as a protective agent for the impregnating substance in each zeolite crystal's interior, and allows regulated time release control of the impregnating substance, thus permitting a controlled diffusion (or absorption) rate in applications in which the coated, impregnated zeolite is employed to absorb contaminants from air or water. Combinations of coated and uncoated zeolite crystals can be chosen to match specific environmental circumstances calculable by analysis of the air or water to be treated.

Abstract: In using calcium-exchanged forms of zeolite X as selective adsorbents for nitrogen in PSA air separation process, it has been discovered that, particularly under certain temperature and pressure conditions, the peak performance is not, as is generally believed, obtained when the calcium content is at a maximum, but rather when the degree of calcium exchange is in the range of 60 to 89 equivalent percent and only when the framework Si/Al.sub.2 ratio of the zeolite is within the range of 2.0 to 2.4.

Abstract: Pressure swing adsorption air and other gas separation operations are carried out using specific preferred zeolite adsorbent compositions based on the symmetry of the framework atoms and cations therein. Specific SiO.sub.2 /Al.sub.2 O.sub.3 and cation/cation ratios for enhanced performance are identified. LiX adsorbent having a silica to alumina ratio on the order of 2.364 provides enhanced PSA performance.

Abstract: Perfluorocarbons are recovered from gas streams by subjecting the gas stream to an adsorption process in a bed of one or more energetically homogeneous adsorbents such as silicon-rich adsorbents of the FAU structure, silicon-rich adsorbents of the BEA structure, silicon-rich adsorbents of the MOR structure. The adsorption process is preferably pressure swing adsorption or temperature swing adsorption.

Abstract: A gas mixture comprised of nitric oxide and, optionally an inert gas, and containing small amounts of nitrogen dioxide, and perhaps moisture and sulfur dioxide, is purified by passing the gas stream through a bed of metal cation-free alumina-deficient zeolites of types Y or ZSM-5. The concentrations of nitrogen dioxide, sulfur dioxide and moisture in the gas stream are reduced to about 1 ppm or less as the gas mixture passes through the bed of zeolite.

Abstract: Lithium/alkaline earth metal X zeolites in which the lithium:alkaline earth metal equivalent ratio is from about 95:5 to about 50:50 and lithium/alkaline earth metal A zeolites in which the lithium:alkaline earth metal equivalent ratio is from about 10:90 to about 70:30 are useful for separating oxygen and nitrogen from mixtures because they combine high adsorption capacity with high thermal stability.

Abstract: Desiccant-coated substrates, regeneratable rotary dehumidification wheels and other devices for gas (e.g., air) treatment using those substrates, and processes for making them are disclosed. The substrates may have coatings in thicknesses of from about 2 to about 10 mils containing particles of one or more adsorbent desiccants and an organic water-based binder. The desiccant particles retain a high fraction of their original adsorption capacity because the pores of the desiccant particles contain a pore-clearing agent prior to the binder setting and the pore-clearing agent leaves the pores during the manufacturing process to prevent the binder from blocking the pores. In preferred embodiments a mixture of different desiccants is used and a particle suspending agent keeps the particles well-mixed so that the desiccant particles in the coated substrate will be as well-mixed as possible. The suspending agent may also function as the pore-clearing agent.

Abstract: A fuel-sorbing device excellent in sorbing evaporated fuel includes a sorbent of layered porous silica for capturing evaporated fuel and a container which houses the sorbent and into which the evaporated fuel is introduced. The layered porous silica is composed of a plurality of superposed sheets made of a framework of SiO.sub.2. Adjacent sheets are partly bonded each other to form a three-dimensional framework having a large number of pores. The sorbent can be used in combination with an organic polymer sorbent, so as to sorb evaporated fuel in two stages.

Abstract: A process is provided for the removal and recovery of chlorine from a chlorine plant offgas stream. A pressure swing adsorption (PSA) process is used to remove from the chlorine plant offgas a vent gas stream comprising hydrogen and a tail gas stream comprising chlorine which is subsequently liquefied. The PSA zone comprises at least 2 adsorption beds, wherein each of the adsorption beds comprises a first adsorption layer and at least a second adsorption layer. The first adsorption layer contains a weak adsorbent selective for the adsorption of chlorine and has a large pore structure with 12 member rings or more. The second adsorption layer contains a strong adsorbent selective for the adsorption of chlorine and has a small pore structure with 10 member rings, or less. The vent gas withdrawn from the process is essentially free of chlorine.

Abstract: The present invention is directed to a process for separating nitrogen from gas mixtures containing nitrogen and less strongly adsorbed components such as oxygen, hydrogen, argon or helium at ambient temperatures or above by use of a magnesium exchanged, sodium A-zeolite in a preferred level of magnesium exchange and an appropriate pressure range for adsorption and desorption of bulk gases which provides improved recovery and reduced bed size factor.

Abstract: A process for removal and recovery of arsenic from a gas comprising contacting a supported sorbent with an arsenic-containing gas, adsorbing the arsenic with the supported sorbent, desorbing the arsenic from the supported sorbent, and collecting the desorbed arsenic.

Abstract: A process for removal of contaminants from a fluid stream comprising adsorbing the contaminants with an adsorbent, contacting the resulting contaminant-laden adsorbent with a heated fluid, incinerating a portion of the contaminant-laden fluid, mixing at least a portion of the products of combustion with the remaining portion of contaminant-laden fluid, recirculating the mixture of contaminant-laden fluid and combustion products through the adsorbent to increase the concentration of contaminants in the mixture, and incinerating at least a portion of the recirculated mixture.

Abstract: A method and apparatus for drying a non-aqueous liquid electrolyte through the non-contact use of a desiccant includes a closed system having separate containers for the electrolyte and the desiccant. The closed system is charged with an inert gas, and a means is provided to circulate the gas between the containers. A stirring means is provided to stir the electrolyte to facilitate the release of water from the electrolyte.

Abstract: An enclosure for providing both a moisture free and particle free environment is disclosed. A portion of the inner surface of the enclosure, that comprises an electronic device sealed in a container, is coated with a pressure sensitive adhesive comprising 4-40 percent, by volume, of a solid desiccant. The preferred adhesive is a silicone pressure sensitive adhesive and the preferred desiccant is zeolite.

Abstract: A desiccant composition having a moderate Langmuir Type 1 moisture adsorption isotherm with a separation factor of from 0.05 to 0.13 is disclosed. The composition contains silica gel, a modified 13.times. molecular sieve (modified by replacing at least 20% of the sodium cations with other metallic cations, e.g., potassium cations), and desirably a hydrophobic adsorbent (desirably a hydrophobic molecular sieve). The composition may be used as the desiccant in a rotary regeneratable dehumidification wheel, thereby significantly enhancing dehumidification performance and simultaneously removing a significant proportion of the airborne pollutants typically contained in indoor and outdoor air.

Abstract: Adsorbent material well adapted for the purification of gases (notably by the PSA and TSA methods) by adsorbing impurities therefrom that are more polar or polarizable than the gases to be purified, e.g., nitrogen, the oxides of carbon and hydrocarbons, comprises a matrix of a type 5A zeolite molecular sieve and a kaolinite clay binder therefor, the clay binder having a concentration of at least 75% by dry weight of kaolinite and a maximum quartz concentration of 20% by dry weight.

Abstract: In processes for removing mercury vapor from natural gas streams by selective adsorption in fixed adsorbent beds, water is invariably adsorbed along with the mercury impurity. During the periodic purge regeneration of the adsorbent bed it is desirable to recover as much as possible of the desorbed mercury in the spent regeneration gas in liquid form to avoid reintroducing the mercury into the environment. Cooling this spent regeneration gas under the high pressure conditions involved to condense the mercury can result in the highly undesirable formation of hydrocarbon hydrates if temperatures low enough to condense an adequate amount of mercury are employed. In the process of the present invention, the spent regeneration gas stream, from which some mercury has been removed by cooling, is further treated in a desiccant bed so that it is possible to cool it further in order to condense and remove additional mercury without encountering hydrocarbon hydrate formation.

Abstract: In the purification of natural gas streams to remove mercury by adsorption procedures, environmental pollution is avoided by using a condenser in conjunction with the adsorption beds in a manner such that the mercury vapor contained in the purge gas used to regenerate the adsorption beds is covered entirely as a liquid rather than being vented from the purification system as mercury vapor.

Abstract: This invention relates to molecular sieve compositions and processes for using the molecular sieves. The molecular sieves have a three-dimensional microporous crystalline framework structure of tetrahedral oxide units of AlO.sub.2, SiO.sub.2, TiO.sub.2 and/or FeO.sub.2. These molecular sieves can be prepared by contacting a starting zeolite with a solution or slurry of a fluoro salt of titanium and/or iron under effective process conditions to extract aluminum from the zeolite framework and substitute titanium and/or iron. The molecular sieves can be used as catalysts in hydrocarbon conversion processes and other processes.

Abstract: A pressure swing adsorption plant for the separation of gas mixtures includes at least one pressure vessel containing an adsorbent bed that is able preferentially to adsorb at least one component of the gas mixture. The pressure vessel has an inlet at its top for the feed gas mixture, an outlet at its bottom for non-adsorbed gas and at least one heat conductive member containing a liquid medium arranged within the bed such that, in operation, heat is able to be conducted by convection through the liquid from a region of maximum temperature at or near the bottom of the bed to a region of minimum temperature at or near the top of the bed.

Abstract: Improved apparatus for fractionating fluid mixtures by pressure swing molecular adsorption employing a rotary distributor valve and an array of adsorber columns. The columns are, in one embodiment, contained within a product holding tank or, in another embodiment, attached to a product tank. The valve sequences to provide a quasi steady-state flow, allowing optimization of adsorption/desorption cycles, and eliminating most of the valves, switches and plumbing usually required.

Abstract: The present invention is directed to a process for separating nitrogen from gas mixtures containing nitrogen and less strongly adsorbed components such as oxygen, hydrogen, argon or helium by use of an at least binary exchanged X-zeolite having lithium and a divalent cation selected from the group consisting of barium, cobalt, copper, chromium, iron, magnesium, manganese, nickel, zinc and mixtures thereof in a ratio of preferably 5% to 50% of the divalent cation and 50% to 95% lithium.

Abstract: The present invention is directed to adsorptive separation of nitrogen with active adsorbent phases with high N.sub.2 capacity and high heats of adsorption when diluted with inert material at levels ranging from 5% to 80%. The presence of diluent reduces the temperature swings in the adsorbent bed, which increases the utilizable effective N.sub.2 working capacity and decreases the relative amount of O.sub.2 left unrecovered on the active adsorbent phase. The net result is equal or better process performance allowing utilization of a lower amount of active adsorbent phase. Use of a diluent having a higher heat capacity than that of the active adsorbent phase increases these benefits, but dilution effects are beneficial even for diluents with heat capacities equal to or lower than that of the active adsorbent phase.

Abstract: A method for removing mercury from natural gas comprises addition of a sulfur-containing agent to form sulfides of mercury, addition of organic base to absorb hydrogen sulfide, and subsequent contact of said natural gas with a molecular sieve to remove water therefrom, further comprising contacting said organic base-containing natural gas with a guard bed to substantially remove said organic base prior to said removing of water.