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, superior 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.

Abstract: The invention relates to a process for removing hydrogen halides from hydrocarbon containing streams. More particularly, the invention relates to a process and an HCl sorbent for the removal of HCl and other hydrogen halides from hydrocarbon streams to prevent the formation of green acids. The sorbent has a high capacity for sorption of HCl, sufficient physical strength to permit operation in packed bed form, and catalytic inertness to not causing the oligomerization reactive hydrocarbons such as olefins, diolefins. The HCl sorbent comprises an admixture of magnesium hydroxide and a hydrogen halide reactive component such as calcium hydroxide or oxide with at least one or more metal oxide, hydroxide or carbonate wherein the magnesium is present in an amount greater than about 5 mol-% of the total cation content of the sorbent.

Abstract: An adsorption arrangement in combination with a catalytic hydrocarbon conversion process suspends non-hydrocarbon materials that act to enhance the operation of the conversion zone by using an adsorption zone arrangement to keep the compounds in recirculation about the reaction zone. The process of this invention is particularly useful for the isomerization of hydrocarbons wherein the adsorption zone arrangement operates to maintain chloride compounds in the reaction zone and to prevent contamination of product streams with the chloride compounds. This invention can be used in combination with traditional adsorptive methods of removing contaminant from feedstreams that enter reaction zones. The invention is also useful for sulfided catalysts where it is desirable to maintain sulfur within the reaction zone and keep sulfur contamination from entering product streams.

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: 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: 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: An adsorption arrangement in combination with a catalytic hydrocarbon conversion process suspends non-hydrocarbon materials that act to enhance the operation of the conversion zone by using an adsorption zone arrangement to keep the compounds in recirculation about the reaction zone. The process of this invention is particularly useful for the isomerization of hydrocarbons wherein the adsorption zone arrangement operates to maintain chloride compounds in the reaction zone and to prevent contamination of product streams with the chloride compounds. This invention can be used in combination with traditional adsorptive methods of removing contaminant from feedstreams that enter reaction zones. The invention is also useful for sulfided catalysts where it is desirable to maintain sulfur within the reaction zone and keep sulfur contamination from entering product streams.

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: Processes are disclosed for the separation of hydrogen sulfide from feedstreams containing hydrogen sulfide and hydrocarbons by adsorption using a clinoptilolite adsorbent containing cations having ionic radii of from about 1.10 to 1.40 Angstroms. The processes can provide substantially enhanced adsorption capacities as compared with other adsorbents such as Zeolite 4A. As a result, a throughput of existing sulfur adsorption plants can be increased, e.g., by about 100%. The processes can be operated at elevated adsorption temperatures, e.g., greater than about 200.degree. F., and thus are particularly suitable when integrated with other processing steps such as hydrocarbon conversion reactions that utilize catalysts which are sulfur-sensitive. In addition, the clinoptilolite adsorbents of the present invention have a high tolerance to environments that comprise halides, e.g., HCl.

Abstract: Clinoptilolites, including both natural and synthetic clinoptilolites which have been ion-exchanged with metal cations such as lithium, sodium, potassium, calcium, magnesium, barium, strontiun, zinc, copper, cobalt, iron and manganese, are useful for the removal of traces of ammonia from streams of hydrocarbons having kinetic diameters of not more than about 5 .ANG.. This invention relates to the process of producing the modified clinoptilolite adsorbent.

Abstract: Natural clinoptilolites which have been ion-exchanged with particular proportions of metal cations such as lithium, sodium, potassium, calcium, magnesium, barium, strontium, zinc, copper, cobalt, iron and manganese, are novel and useful for the removal of traces of carbon dioxide and water from streams of hydrocarbons having kinetic diameters of not more than about 5.

Abstract: Clinoptilolites, including both natural and synthetic clinopilolites which have been ion-exchanged with metal cations such as lithium, sodium, potassium, calcium, magnesium, barium, strontium, zinc, copper, cobalt, iron and manganese, are useful for the removal of traces of ammonia from streams of hydrocarbons having kinetic diameters of not more than about 5.ANG.. The purified hydrocarbons are useful for producing polyolefins.

Abstract: Clinoptilolites, including both natural clinoptilolites and those which have been ion-exchanged with metal cations such as lithium, sodium, potassium, calcium, magnesium, barium, strontium, zinc, copper, cobalt, iron and manganese, are useful for the removal of traces of carbon dioxide and water from streams of hydrocarbons having kinetic diameters of not more than about 5 .ANG..

Abstract: The highly lithium exchanged forms of zeolite X, particularly the low silica forms of zeolite X which contain more than ninety equivalent percent lithium cations, have been found to exhibit extraordinary capacities and selectivities for nitrogen adsorption. Such adsorbents are to a surprising degree effective in separating nitrogen from gas streams such as air and mixtures of nitrogen with less polar substances such as hydrogen, argon and methane. Pressure swing adsorption separation process are well suited to take advantage of the exceptional properties of these absorbents.

Abstract: Adsorbent compositions are prepared by the addition of crystalline molecular sieves to latexes. The resulting latex polymer bonded zeolites have improved attrition resistance in separations involving an aqueous medium.

Abstract: Carbon dioxide is selectively adsorbed and separated from non-acidic gases such as nitrogen, hydrogen and methane using a pressure swing adsorption process in a fixed adsorption bed containing a faujasite type of zeolitic aluminosilicate containing at least 20 equivalent percent of at least one cation species selected from the group consisting of zinc, rare earth, hydrogen and ammonium and containing not more than 80 equivalent percent of alkali metal or alkaline earth metal cations.

Abstract: A process for the separation of arabinose is disclosed which comprises the selective adsorption of same on BaX zeolitic molecular sieves. The process is especially useful for separating arabinose from mixtures of sugars containing arabinose.

Abstract: A process for the bulk separation of sorbitol from a solution of a carbohydrate mixture by selective adsorption on a zeolite molecular sieve having a faujasite type structure and having predominantly Ca.sup.++ cations in association with the AlO.sub.2.sup.- tetrahedra thereof.

Abstract: A process for the separation of arabinose is disclosed which comprises the selective adsorption of same on BaX zeolitic molecular sieves. The process is especially useful for separating arabinose from mixtures of sugars containing arabinose.

Abstract: A process for the separation of mannose is disclosed which comprises the selective adsorption of same on certain types of zeolitic molecular sieves. The process is especially useful for separating mannose from glucose epimerization product or plant tissue hydrolyzate, using zeolites selected from the group consisting of BaX, BaY, SrY, NaY and CaY.