Abstract: A process scheme for the recovery of high purity p-xylene or p-xylene and ethyl benzene from C.sub.8 aromatics is described. In the process, zeolites such as ZSM-5 type, zeolite beta and ZSM-11 with optimum silica alumina ratio is used as the adsorbent and light hydrocarbons, such as C.sub.5 is used as the desorbent. The process system is operated isothermally at low temperature and low pressures.

Abstract: Organic feedstocks containing at least one impurity component which is more strongly adsorbed on molecular sieve adsorbents than the host feedstock are purified of the said impurity by passage in the liquid phase through a fixed bed of the adsorbent whereby the impurity is selectively adsorbed and the purified feedstock recovered in unusually high yield by a novel bed regeneration procedure involving the use of a portion of the purified feedstock in the vapor phase to countercurrently remove the liquid held in the bed void space, a relatively non-sorbable purge gas to sequentially displace the purified feedstock vapor from the bed followed by a displacement of the non-sorbable purge gas from the bed void space using another portion of the purified feedstock in the vapor phase, and finally cooling and refilling the bed in a direction cocurrent with the flow of feedstock into the bed during the adsorption purification stage with a portion of the purified feedstock in the liquid phase.

Abstract: Disclosed is a method of separating organic or organometallic materials under supercritical fluid conditions, the method comprising the steps of providing a bed of packing material selected from a metal oxide/hydroxide support material having phsophorous-containing organic molecules bonded to reactive sites on said support material, alumina and alumina-containing mixtures. The materials are introduced to the bed and a fluid is added to the bed under supercritical fluid conditions. The fluid removes one of the materials from the bed.

Abstract: A chromatographic process able to separate para-xylene from C.sub.8 isomers and C.sub.9 aromatics. In the process, the para-xylene-containing feed mixture is contacted with an X or Y zeolite adsorbent having Group IA or IIA cations, e.g., barium and/or potassium at exchangeable cationic sites. The para-xylene is selectively adsorbed onto the adsorbent. The feed is then removed from the adsorbent and the para-xylene recovered by desorption with diethyltoluene. The C.sub.9 's and the other xylene isomers in the raffinate, can be separated from this heavy desorbent by fractionation of the raffinate and the desorbent recycled to the process.

Abstract: A process is disclosed for separation of ortho chlorotoluene and ortho-dichlorobenzene from their meta and para isomers by use of a specific crystalline aluminophosphate adsorbent which selectively removes the above ortho aromatic isomers. The selectively adsorbed ortho aromatic isomers are removed from the adsorbent through a desorption step.

Abstract: This invention relates to a process for increasing the octane of a refinery gasoline pool by segregating components which are increased in value by isomerization from those which are diminished in octane value by isomerization. The preferred feed stream of this process comprises di-branched paraffins, mono-methyl-branched paraffins and normal paraffins from which mono-methyl-branched and normal paraffins are selectively captured by a shape-selective molecular sieve. The preferred separatory shape-selective molecular sieve has a pore size of 5.5.times.5.5 to 4.5.times.4.5A but excluding 4.5.times.4.5A. Mono-methyl-branched paraffins and normal paraffins are removed from the shape-selective molecular sieve and isomerized in an isomerization zone to form di-methyl branched paraffins. An isomerization zone effluent stream is produced comprising unisomerized normal paraffins, mono-methyl-branched paraffins and di-branched paraffins.

Abstract: Process for eliminating jointly arsenic and carbon oxysulfide from an unsaturated hydrocarbon cut, wherein said hydrocarbon cut is contacted with an absorbing mass containing a support and lead oxide, comprising contacting the hydrocarbon cut in the liquid phase.

Abstract: A two stage adsorptive separation process for recovering purified 2,6 Dimethylnaphthalene ["2,6 DMN"] from a fresh feed mixture comprising 2,6 DMN and at least one isomer thereof, which process comprises a first stage, employing a first stage adsorbent and desorbent material and operating at 2,6 DMN rejective conditions, with at least a portion of the raffinate product of such stage being fed to a second stage, employing a second stage adsorbent and desorbent material and operating at 2,6 DMN extractive conditions, thereby producing a second stage extract product containing purified 2,6 DMN. The adsorbent(s) and desorbent material(s) used in the process will depend upon the embodiment of the process employed. The most preferred embodiment of the subject invention concerns the use of a distinct adsorbent in each stage and a desorbent material common to both stages.

Abstract: The chromatographic adsorption separation of indene from petrochemical or synthetic feed mixtures with an Na- or K-exchanged X- or Y-zeolite and toluene, benzene, fluorobenzene or other halogen- or alkyl-substituted monocyclic aromatic desorbents. Selectivity of the separation is dependent on water content, from 1-8% (wt.), of the adsorbent.

Abstract: This invention relates to a process for the production of an isomerate gasoline blending component where the octane value of the isomerate is increased relative to prior art processes utilizing single separatory sieves. After respective isomerization of feed streams comprising C.sub.6 or C.sub.6.sup.+ normal paraffins, a multiple separatory sieve is located to selectively adsorb unreacted normal paraffins and mono-methyl-branched paraffins from an isomerate product stream. The preferred first separatory sieve is exemplified by a calcium 5A sieve which can adsorb normal paraffins while allowing mono-methyl-branched paraffins and more higly branched paraffin to pass to a second separatory sieve. The second sieve comprises a shape-selective zeolite having a pore size intermediate 5.5.times.5.5 and 4.5.times.4.

Abstract: A pretreatment process for removal of contaminants from a light hydrocarbon feedstock is presented. The feedstock is passed to a first adsorption zone containing a molecular sieve and thereafter passed to a second adsorption zone containing activated alumina. The process produces a hydrocarbon feedstock substantially free of sulfur compounds, oxygenates, and water. Such a process finds utility as a feed pretreatment step preceding a catalytic isomerization process.

Abstract: Titanium-aluminum-silicon-oxide molecular sieves are disclosed having use as molecular sieves and as catalyst compositions in hydrocarbon conversion and other processes. The molecular sieves have a unit empirical formula on an anhydrous basis ofmR: (Ti.sub.x Al.sub.y Si.sub.z)O.sub.2wherein "R" represents at least one organic+ emplating agent; "m" represents the moles of "R" present per mole of (Ti.sub.x Al.sub.y Si.sub.z)O.sub.2 ; and "x", "y" and "z" represent the mole fractions of titanium, aluminum and silicon, respectively, present as tetrahedral oxides. The molecular sieve is useful in separating molecular species having different degrees of polarity and/or kinetic diameters.

Abstract: Ethylbenzene is separated from a paraxylene depleted feedstream containing meta-xylene by contacting the feedstream with a K-substituted Type Y zeolite, passing through the zeolite a selected desorbent, and recovering a stream enhanced in concentration of ethylbenzene relative to meta-xylene. Preferably, the desorbent is an aromatic hydrocarbon.The zeolite may contain an effective amount up to 10% by weight of total water and up to about 4% by weight methanol.

Abstract: The invention relates to a process for selectively adsorbing ethylbenzene from a stream containing one or more isomeric xylenes. The ethylbenzene is adsorbed on a gallium Beta zeolite. A desorbent comprising para-dialkylbenzene gives the zeolite good ethylbenzene selectivity over the xylenes.

Abstract: A process for separating a C.sub.10 aromatic isomer, particularly paradiethylbenzene, from a feedstream containing a mixture of C.sub.10 aromatic isomers by contacting the feedstream with a bed of the adsorbent zeolite beta. The adsorbed C.sub.10 aromatic isomer is removed from the adsorbent by desorption.

Abstract: This invention relates to a process for the production of an isomerate gasoline blending component where the octane value of the isomerate is increased relative to the overall cost of the process. After isomerization, the separatory sieve of this invention selectively adsorbs unreacted normal paraffins and mono-methyl-branched paraffins but not di-methyl-branched paraffins. The preferred separatory sieve is ferrierite. This process is an improvement over prior Total Isomerization Processes (using a calcium-5A separatory sieve) to recycle only n-paraffins to the isomerization zone.

Abstract: The separation of para-xylene from a mixture of C.sub.8 aromatic isomers in a zeolite adsorption process is improved by use of water as the desorbent. Increased desorption efficiency is obtained by the addition to the water of small amounts of a C.sub.1 to C.sub.8 alcohol, an anionic surfactant, an alkali solution or a mixture thereofs. Separation of water from the para-xylene product and raffinate is accomplished by phase separation.

Abstract: A high surface area substrate with controlled pore size and slot geometry is used in an adsorbing process. The material is made by depositing at least two materials in alternating layers. The film is then broken up and one of the materials is etched away to produce a slotted surface structure. These slots can add size and shape selectivity to separations and catalytic processes which because of the uniform and controllable dimensions (>5A) would be superior to that obtainable from zeolites and clays.

Abstract: Magnetizable adsorbent particles suitable for use in a magnetically stabilized fluidized bed and with a smaller particle size than conventionally formed composite adsorbents are prepared by introducing magnetizable particles such as magnetite or iron into a reaction mixture for forming a zeolite having adsorbent properties, such as zeolite Y. The zeolite is formed as a coating on the magnetizable particle.

Abstract: This invention relates to a fluidized bed process. More particularly, the present invention is a process for operating a magnetically stabilized fluidized bed by using a magnetizable fluid to fluidize solid particulate nonmagnetizable fluidizable particles. The operating conditions are such that there is substantially no random motion or time-varying pressure fluctuation as measured at a point within the bed.

Abstract: The viscosity index of synthetic lubricant stocks such as those produced by olefin oligomerization is increased by contacting such stocks with a solid acidic isomerization catalyst such as boron trifluoride at elevated temperatures, say above about 200.degree. C. The high viscosity index fractions of the resulting product may be sorbed by a shape-selective zeolite such as ZSM-5 and recovered to produce a high VI lubricant.

Abstract: An improved method for fluidized catalytic cracking of a selected portion of a paraffinic hydrocarbon feedstock in which a paraffinic chargestock for a fluid catalytic cracking unit is processed for the separation of at least a part of its paraffinic components from non-paraffins by means of a zeolite composition which acts both as a molecular sieve and a cracking catalyst. The paraffins-containing fraction adsorbed on the molecular sieve is subjected to catalytic cracking in a riser-type fluid catalytic cracking reaction zone at a temperature in the range of 650.degree. to 700.degree. C. under subatmospheric pressure conditions for the production of light olefins.

Abstract: The invention relates to a process for selectively absorbing ethylbenzene from a stream containing one or more isomeric xylenes. The ethylbenzene is adsorbed on an Rb-substituted Type X zeolite. Certain desorbents, of which n-alkylbenzenes are preferred, give the zeolite good ethylbenzene selectivity over the xylenes.

Abstract: Iso-butane is separated from normal butane in a pressure swing adsorption system of at least three adsorbent beds, each adapted to selectively adsorb normal butane from a mixture thereof with iso-butane. The adsorption front of normal butane formed in each adsorbent bed upon the passage of the feed gas mixture thereto is moved through the bed to an extent enhancing the utilization of the adsorptive capacity thereof. By combinations of depressurization and repressurization together with purge, desirable product purity levels are obtained, while the cost of adsorbent equipment and of operation are reduced to the extent possible consistent with the purity requirements of a given application.

Abstract: Titanium-containing molecular sieves are disclosed having use as molecular sieves and as catalyst compositions in hydrocarbon conversion and other processes the instant invention employs novel titanium-containing molecular sieves comprising titanium, aluminum, phosphorus and oxygen and are generally employable in separation and hydrocarbon conversion processes.

Abstract: Normal paraffins present in high concentrations in light naphtha streams are separated from non-normal paraffins in a four or more bed adsorption system employing, on a cyclic basis, the processing steps of (1) cocurrent purge/adsorption, (2) cocurrent feed/adsorption, (3) countercurrent purge and (4) countercurrent displacement. A processing sequence is employed wherein the cocurrent purge/adsorption and countercurrent purge steps are carried out on a discontinuous basis, while cocurrent feed/adsorption and countercurrent displacement steps are carried out in overlapping sequence.

Abstract: The invention relates to a process for selectively adsorbing ethylbenzene from a stream containing one or more isomeric xylenes. The ethylbenzene is adsorbed on Cs-substituted Type X zeolite. Certain alkyl substituted benzene desorbents give the zeolite good ethylbenzene selectivity over the xylenes.

Abstract: Paraxylene is separated from a feedstream containing ethylbenzene and other xylenes by contacting the feedstream preferably with a K-substituted Type Y zeolite, passing through the zeolite a selected additive, and recovering a stream enhanced in concentration of paraxylene relative to ethylbenzene. Preferably, the additive is a cyclic nitrogen containing compound such as pyrrole or pyridine.

Abstract: The invention relates to a process for selectively adsorbing ethylbenzene from a stream containing one or more isomeric xylenes. The ethylbenzene is adsorbed on a Beta zeolite. Certain desorbents, of which paradiethylbenzene is preferred, give the zeolite good ethylbenzene selectively over the xylenes.

Abstract: Aromatic hydrocarbon impurities are removed from a liquid paraffin containing the same by contacting the liquid paraffin in the liquid phase at relatively low temperatures with an X-type zeolite molecular sieve material. The contacting is performed without recycle and purified liquid paraffin containing less than about 0.01% by weight aromatics is obtained.

Abstract: A process for separating a C.sub.9 aromatic isomer from a feed stream containing a mixture of C.sub.9 aromatic isomers by contacting the feed stream with a bed of the adsorbent zeolite beta. The adsorbed C.sub.9 aromatic isomer is removed from the adsorbent by desorption.

Abstract: There is provided a process for the separation of aromatic hydrocarbons mixtures into single components, in which the mixtures in vapor phase pass onto an adsorption bed formed by a potassium-exchanged Y zeolite, which is preventively saturated with desorbent vapors. According to the invention the desorbent used is isopropylbenzene in vapor phase. This facilitates the quick separation of the pure components, with the exception of the presence of desorbent. The process according to this invention is quicker in comparison to traditional ones. It requires the use of lower charges of desorbent and allows the separation of single pure components of the mixtures. It especially improves the paraxylene separation in higher concentrations with respect to the desorbent.

Abstract: A process able to separate ortho-xylene from the other C.sub.8 aromatics. In the process the ortho-xylene-containing feed mixture is contacted with an X-type zeolite having silver cations at exchangeable cationic sites which has been subjected to a reduction step. The ortho-xylene is selectively adsorbed onto the adsorbent. The feed is then removed from the absorbent and the ortho-xylene recovered by desorption with para-diethylbenzene. The process is particularly amenable to the simulated moving bed flow scheme.

Abstract: A process for selective separation of a linear aliphatic compound in admixture with at least one non-linear hydrocarbon compound, said compounds having a critical dimension of less than 6.8 Angstrom Units for sorption, which comprises contacting the mixture with zeolite ZSM-11, said zeolite being characterized by a silica:alumina mole ratio of at least 12, to effect selective sorption of said linear aliphatic compound by said zeolite.

Abstract: A process for separating ethylbenzene from a feed mixture comprising ethylbenzene and at least one xylene isomer. The mixture is contacted with an adsorbent comprising a barium cation exchanged type-X zeolite containing from about 3.0 to about 6.0 wt. % H.sub.2 O. The unadsorbed portion of the feed mixture is removed from the adsorbent and the ethylbenzene recovered by desorption with benzene.

Abstract: Lubricant components of high viscosity index are selectively separated from hydrocarbon base stocks by a selective sorption process using an intermediate pore size zeolite such as ZSM-5 as the sorbent. The process is of particular utility with synthetic lubricant stocks produced by the oligomerization of light olefins. The sorbed components may be desorbed from the zeolite to recover a high VI lubricant.

Abstract: A process for separating a normal C.sub.6 olefin hydrocarbon from a mixture of the same with a C.sub.6 olefin branched chain and/or cyclic hydrocarbon. The process comprises contacting the mixture at separation conditions with a molecular sieve comprising a crystalline silica. The normal C.sub.6 olefin hydrocarbon is selectively retained and will be recovered from the molecular sieve by displacement with a displacement material comprising pentene-1 or butene-1. The process preferably employs a simulated moving bed.

Abstract: A process for separating the ortho-isomer from a feed mixture comprising at least two bi-alkyl substituted monocyclic aromatic isomers, including the ortho-isomers, the isomers having from 9 to about 18 carbon atoms per molecule. The process comprises contacting, at adsorption conditions, the feed with an adsorbent comprising a crystalline aluminosilicate consisting essentially of a sodium or calcium Y-type zeolite or sodium X-type zeolite which selectively adsorbs the ortho-isomers. The feed is removed from the adsorbent, and the ortho-isomers recovered by desorption at desorption conditions with a desorbent material comprising a C.sub.8 or heavier monocyclic aromatic with a boiling point at least 5.degree. C. different than that of the feed mixture when the adsorbent is the sodium Y-type zeolite, or a C.sub.8 or lighter monocyclic aromatic when the adsorbent is a sodium X or calcium Y-type zeolite.The process is particularly amenable to the employment of a simulated moving bed flow scheme.

Abstract: An invention is described in which a portion of one of the product streams from an adsorption system is used to wash a recycle gas stream in order to improve the quality of one of the products.

Abstract: An improved technique for sorption of certain members of a ZSM-5 type of zeolites is provided. The class of zeolites is characterized by a silica to alumina mole ratio greater than 12 and a Constraint Index within the approximate range of greater than about 2 to about 12. The process of this invention involves sorption and/or selective separation of bicyclic fused-ring aromatic compounds, having a critical dimension less than 6.8 Angstrom units.

Abstract: A process for the separation of normal C.sub.4 hydrocarbons from isobutylene. A mixture of the normal C.sub.4 hydrocarbons and isobutylene is contacted with a molecular sieve comprising silicalite which is selective for the normal C.sub.4 hydrocarbons. The isobutylene is then recovered in the raffinate stream and the normal C.sub.4 hydrocarbons recovered by displacement with pentene-1.

Abstract: A process for separating a normal paraffin hydrocarbon from a mixture of the same with a cyclic and/or branched chain paraffin hydrocarbon. The process comprises contacting the mixture at a temperature of from about 120.degree. C. to about 140.degree. C. with a zeolite free molecular sieve comprising silicalite. The normal paraffin hydrocarbon is selectively retained and will preferably be recovered from the molecular sieve by displacement with a displacement material.

Abstract: An improved adsorptive separation process by the selective sorption properties of certain members of a novel class of zeolites is provided. The novel class of zeolites is characterized by a silica to alumina mole ratio greater than 12 and a Constraint Index within the approximate range of greater than 2 to about 12. The process of this invention involves selective separation of waxy paraffinic compounds in admixture with stocks containing paraffinic compounds, e.g. crude oils, heavy oils, distillate oils and lube base oils, by contacting the mixture with a zeolite having a SiO.sub.2 /Al.sub.2 O.sub.3 mole ratio of at least about 12 and a Constraint Index within the range of greater than 2 to about 12 to effect the selective sorption of said waxy paraffinic compounds by said zeolite.

Abstract: A method is disclosed for hydrocracking a hydrocarbon feedstock having a propensity to form polynuclear aromatic compounds without excessively fouling the processing unit. The hydrocracking method includes contacting the hydrocarbon feedstock with a crystalline zeolite hydrocracking catalyst, contacting at least a portion of the resulting unconverted hydrocarbon oil containing polynuclear aromatic compounds with an adsorbent which selectively retains polynuclear aromatic compounds and recycling unconverted hydrocarbon oil having a reduced concentration of polynuclear aromatic compounds to the hydrocracking zone.

Abstract: An improved hydrocarbon separation process by the selective sorption properties of certain members of a novel class of zeolites is provided. The novel class of zeolites is characterized by a silica to alumina mole ratio greater than 12 and a Constraint Index within the approximate range of greater than about 2 to about 12. The process of this invention involves selective separation of higher molecular weight hydrocarbon compounds in admixture with lower molecular weight hydrocarbon compounds within a homolgous series by contacting the respective mixture with a zeolite having a SiO.sub.2 /Al.sub.2 O.sub.3 mole ratio of at least about 12 and a Constraint Index with the approximate range of greater than 2 to about 12, to effect the selective sorption of said higher molecular weight hydrocarbon compounds by said zeolite.

Abstract: An improved hydrocarbon separation process by the selective sorption properties of certain members of a novel class of zeolites is provided. The novel class of zeolites is characterized by a silica to alumina mole ratio greater than 12 and a Constraint Index within the approximate range of greater than about 2 to about 12. The process of this invention involves selective separation of non-aromatic compounds in admixture with aromatic compounds by contacting the mixture with zeolite ZSM-5, ZSM-11, ZSM-23 or ZSM-35, said zeolite having a SiO.sub.2 /Al.sub.2 O.sub.3 mole ratio of at least about 12, to effect the selective sorption of said non-aromatic compounds by said zeolite.

Abstract: A method is disclosed for regenerating a solid adsorbent which has been used to remove oxygen-containing hydrocarbonaceous compounds, water or sulfur-containing compounds from a hydrocarbon stream. The method is preferably applied to molecular sieves which have been used to remove ethers, alcohols and/or water from a light liquid phase hydrocarbon stream such as a stream which is rich in C.sub.4 hydrocarbons. The regeneration method includes stripping the adsorbent with a low temperature hydrogen-rich gas stream, which preferably has a temperature below about 200.degree. F., and then gradually increasing the temperature of the gas stream to customary regeneration temperatures.

Abstract: A method for separating straight chain hydrocarbons from a hydrocarbon fraction having straight chain hydrocarbons, nonstraight chain hydrocarbons, and a sulfur compound, includes the steps of contacting the hydrocarbon fraction with a 5A zeolite having crystals of an average size larger than about 700 angstroms which selectively absorbs the straight chain hydrocarbons to the substantial exclusion of the nonstraight chain hydrocarbons and sulfur compound. Large zeolite crystals are found to have a much longer useful life in this separation method than zeolite crystals having an average size of less than about 700 angstroms as measured along one edge of the zeolite crystal. The hydrocarbon fraction has more than about 800 wppm total sulfur including more than about 15 wppm mercaptan.

Abstract: Whole crude and residual fractions from distillation of petroleum and like feed stocks are subjected to selective vaporization to prepare heavy fractions of reduced Conradson Carbon and/or metals content by short-term, high temperature riser contact with a substantially inert solid contact material of low surface area in a selective vaporization zone. High boiling point components of the charge which are of high Conradson Carbon number and/or high metal content remain on the contact material as a combustible deposit which is then burned off in a combustion zone whereby the contact material is heated to a high temperature for return to the selective vaporization zone to supply the heat required therein. Equilibrium FCC catalyst, previously treated to reduce catalytic cracking activity and surface area, is used as the substantially inert solid.

Abstract: Normal paraffins are separated from a hydrocarbon vapor feedstream having 10 to 25 carbon atoms per molecule in a constant pressure process employing a molecular sieve adsorbent and n-hexane for purging and for dilution of gas oil - containing feedstocks. A portion of the countercurrent, desorption purge effluent is employed as a hexane - containing cocurrent purge stream, thereby significantly reducing the required amount of n-hexane purge recycle material, and the size of the equipment and the energy consumed in the processing of said recycle stream. A portion of said countercurrent purge effluent can also be used to provide a source of n-hexane diluent for the gas oil - containing feedstocks, as can the cocurrent purge effluent, resulting in further reduction in required equipment and energy costs, and increasing adsorption efficiency and adsorbent utilization.