Abstract: The present invention describes a method for separating mixtures of aromatics and non-aromatics into aromatic-enriched and non-aromatic-enriched streams by contacting the aromatic/non-aromatics mixture with one side of a polyarylate membrane and selectively permeating the aromatic components through the membrane.

Abstract: The present invention describes a method for separating mixtures of aromatics and non-aromatics into aromatic-enriched and non-aromatic-enriched streams by contacting the mixture with one side of a polyphthalate-carbonate membrane and selectively permeating the aromatic components of the mixture through the membrane.

Abstract: Water is separated from an MEK toluene dewaxing solvent by pervaporation through a polyvinyl alcohol membrane (optionally containing polyacrylic acid) mounted on a polyacrylonitrile support layer.

Abstract: A process and reactor apparatus are disclosed for upgrading paraffinic feedstocks to olefinic and/or aromatic products. Hydrogen diffuses through a selectively permeable membrane from the reaction zone into a combustion zone where it reacts exothermically with an oxygen-containing fluid to supply at least a portion of the endothermic heat of reaction for the paraffin upgrading process. Additionally, in-situ separation of by-product hydrogen from the reactant mixture in the reaction zone increases yield of valuable olefinic and aromatic products.

Abstract: A furfural-containing middle distillate stream is separated by use of a polyethyleneimine membrane which has been cross-linked with a polyisocyanate or a poly(carbonyl chloride) cross-linking agent.

Abstract: A method and system for mechanically removing mercury from natural gas are provided. A mercury trap is positioned at substantially the coldest point in the system before a main heat exhanger. The trap includes a bend in the natural gas flow path, baffles, a demister and/or a perforated cylinder for changing the direction of the flow path and causing mercury to be deposited therein.

Abstract: A process for separating methane from a gaseous mixture containing methane and carbon dioxide by concentration is disclosed, which comprises contacting said gaseous mixture with a membrane comprising a film of a polyimide resin having a repeating unit represented by formula (I): ##STR1## wherein R.sup.1 represents a divalent aromatic, alicyclic or aliphatic hydrocarbon group, or a divalent organic group composed of these hydrocarbon groups linked via a divalent organic linking group. The membrane exhibits excellent selective permeability to carbon dioxide, enabling efficient and stable separation of methane.

Abstract: The invention is a liquid membrane process for separating a gaseous stream into a permeate stream of gases having predominantly lower equilibrium K values and a stream of gases having predominantly higher equilibrum K values, wherein the feed stream and the liquid membrane are operated at a temperature and pressure near a dew point of the feed stream in the two phase liquid/gas region of the phase envelope so that condensate from the feed stream will supply the liquid for the liquid membrane. The liquid membrane process is especially useful to separate hydrocarbon gases, such as a natural gas feed stream containing a large concentration of methane.

Abstract: A pervaporation process for separating organic contaminants from evaporator condensate streams is disclosed. The process employs a permselective membrane that is selectively permeable to an organic component of the condensate. The process involves contacting the feed side of the membrane with a liquid condensate stream, and withdrawing from the permeate side a vapor enriched in the organic component. The driving force for the process is the in vapor pressure across the membrane. This difference may be provided for instance by maintaining a vacuum on the permeate side, or by condensing the permeate. The process offers a simple, economic alternative to other separation techniques.

Abstract: A mixture of at least two constituents A and B is submitted to selective separation across a selective membrane.The membrane comprises an active layer comprising particles of a selective solid (5) dispersed in a continuous non-porous and non-elastomeric polymer phase (4) and a porous support (6). The thickness of the active layer is less than 100 micrometers, advantageously less than 20 micrometers.

Abstract: Process and apparatus for separation of hydrogen, methane, and higher hydrocarbons from gas feed stock. For example, such feedstock is fed to a gas-liquid separator, the resulting gas is treated in a gas-gas membrane separator, the residue is separated in a second gas-liquid separator, and the permeate is separated in a second gas-gas membrane separator; the process may be repeated until the desired effluent specificity is achieved.

Abstract: A process for separating ethane and other higher hydrocarbons from a natural or produced gas stream, having methane as its major constituent. A rubbery permselective membrane, having a propane/methane selectivity of 8 or above, is contacted on its feed side with a gas mixture typically containing methane, ethane, propane, butane, and small amounts of other hydrocarbons, water vapor, hydrogen sulfide and carbon dioxide. Carbon dioxide, water vapor, ethane and the other higher hydrocarbons permeate preferentially through the membrane, and the retentate stream is correspondingly enriched in methane.

Abstract: A process for recovery of hydrocarbon (C.sub.2.sup.+) containing at least two carbon atoms per molecule (e.g. LPG) from a fluid feed containing C.sub.2.sup.+ hydrocarbons and components having at most one carbon atom per molecule (e.g. refinery gas) comprising the following steps:(i) contacting the fluid feed with one side of at least one membrane which is substantially non-permeable for C.sub.2.sup.30 hydrocarbons and removing a first fluid (permeate) containing a substantial amount of components having at most one carbon atom per molecule from the other side of the membrane(s), and(ii) fractionating fluid (retentate) obtained from the one side of the membrane(s) into at least a product containing C.sub.2.sup.30 hydrocarbons and a gaseous product.

Abstract: For deasphalting an asphaltene-containing hydrocarbon oil, employed is a hydrocarbon solvent of 3-8 carbon atoms, resulting in an asphaltic phase and a solution of deasphalted oil in the solvent. The solvent is then separated from the deasphalted oil, by passing the solution tangentially across an inorganic membrane of pore radii from 2 to 15 nonometers: the obtained filtrate has an increased solvent content and may be recycled. The deasphalted oil is selectively retained on the upstream side of the membrane.

Abstract: This invention relates to a method for upgrading heavy oils for use in subsequent hydrocarbon processing. The process is especially suitable for removing metals which are in the form of nickel or vanadium organic compounds and for lowering the Conradson Carbon Residue of the resulting oil. The process includes the steps of diluting the heavy oil with a solvent which completely solvates the oil and subjecting the resulting mixture to an ultrafiltration step using selected membranes.

Abstract: The present invention is an improved process for separating alcohols from ethers and/or hydrocarbon raffinate in an etherification process. The excess alcohol reactant, which forms azeotrope mixtures with the product ethers and C.sub.4 -C.sub.7 raffinate, is removed by passing the liquid azeotrope mixture over a pervaporation membrane which effectively breaks the azeotrope and permeates the alcohol with high flux and high selectivity. In a typical etherification process, one or more pervaporation membrane units can be located ahead of the ether/raffinate distillation step, in conjunction with the distillation step with a liquid side draw, after the distillation step, or a combination of any of the above. The present invention also provides an improved process for separating alcohols from ethers and/or hydrocarbon raffinate in an ether decomposition process for the production of high purity iso-alkene products.

Abstract: Heavy crude oils which contain metal contaminants such as nickel, vanadium and iron may be separated from light hydrocarbon oils by passing a solution of the crude oil dissolved in a cycloparaffinic hydrocarbon solvent containing from about 5 to about 8 carbon atoms by passing through a polymeric membrane which is capable of maintaining its integrity in the presence of hydrocarbon compounds. The light hydrocarbon oils which possess relatively low molecular weights will be recovered as the permeate while the heavy oils which possess relatively high molecular weights as well as the metal contaminants will be recovered as the retentate.

Abstract: The invention is a process for the separation of solvents from hydrocarbons dissolved in the solvents which comprises contacting at elevated pressure a feed solution comprising hydrocarbons dissolved in an aromatic solvent and a polar aliphatic solvent with one side of a dense membrane which is substantially impermeable to the hydrocarbons, and which membrane comprises a layer of a halogen-substituted silicon compound, and recovering the solvents from the other side of the membrane.

Abstract: The process for the separation of gases from a mixture is improved by using as the separation vehicle a single layer semipermeable membrane containing at least about 25 weight percent, based upon the total weight of the membrane, of at least one substituted poly(arylene oxide) polymer containing at least about 50 mole percent of structural units of the formula ##STR1## wherein each R is independently a C.sub.1 to C.sub.8 aliphatic; a C.sub.5 to C.sub.7 cycloaliphatic; a C.sub.1 to C.sub.8 alkoxy radical; a C.sub.6 to C.sub.12 aromatic radical or an inertly-substituted derivative of any one of them, each radical being free of a tertiary alpha-carbon atom, each X is independently hydrogen or a radical at least the size of a chloride radical, with the proviso that at least one X is not hydrogen.

Abstract: A process is disclosed for the recovery of hydrogen and C.sub.6 -plus product hydrocarbons from the effluent stream of a hydrogen-producing hydrocarbon conversion process. The effluent stream of the reaction zone is partially condensed to remove the bulk of the heavy C.sub.6 -plus hydrocarbons, which are then sent to a fractionation zone. The remaining vapor is compressed to a substantially higher pressure. The compressed vapor is then passed into a membrane separation zone in which a hydrogen-rich stream is separated from the compressed vapor. The relatively high pressure nonpermeate portion of the vapor stream which emerges from the membrane separation zone is partially condensed by autorefrigeration. The still high pressure mixed phase fluid is separated into vapor and liquid portions. The liquid phase material is then flashed to produce coolant used to perform the partial condensation.

Abstract: A palladium or palladium alloy is coated with a metal, e.g., titanium, and employed for diffusion of hydrogen.

Abstract: Asymmetric polyimide reverse osmosis membranes of high flux and selectivity for organic liquid separations are described. These membranes are prepared from undegraded polyimide by dissolving from 14-30 wt. % of the undegraded polymer in a dual solvent system comprising a polymer pro-solvent/anti-solvent wherein the pro-solvent is DMF and the anti-solvent is dioxane, wherein the ratio of anti-solvent/pro-solvent ranges from about 10:1 or more-1:1, preferably about 8:1-1.5:1, most preferably about 7:1-3:1; the polymer-solvent mixture is spread into a thin film of the desired thickness and permitted to evaporate for a time just sufficient to permit formation of an asymmetric dense active layer, i.e., within the range 2-120 seconds, preferably 2-60 seconds, most preferably 2-20 seconds before being immersed in a gelation bath.The membranes may be fabricated in the form of sheets, tubes, hollow fibers, etc.

Abstract: A process for the separation of ethanol from water using solvent extraction at elevated pressures is disclosed. Separation is effected by contacting aqueous ethanol with either propylene (propene), allene (propadiene), methyl acetylene (propyne), or methyl allene (1,2-butadiene). This produces two liquid layers which separate because of the difference in their densities, and are easily drawn off as separate streams. The solvent is recovered by reverse osmosis means in a liquid state. The ethanol and water remain in a liquid state and are substantially recovered.

Abstract: Selective extraction solvents such as NMP, phenol or furfural employed for the extraction of specialty oils, i.e. lubricating, transformer and insulating oils, to remove undesirable aromatic components therefrom, is itself recovered from the extract stream and/or raffinate streams by preferential ultrafiltration through selective membranes of regenerated cellulose. The extract stream, because of its higher solvent content, is the preferred stream for solvent recovery treatment by the reverse osmosis membrane permeation technique. Solvent recovery employing membrane permeation exhibits the advantage of not being energy intensive as is distillation or stripping. The solvent is recovered at a high enough flux rate and at a high enough level of purity to be introduced back into the solvent extraction process optionally at some point in the process wherein the composition of the recovered solvent approximately matches the composition of the solvent present in the process at the point of introduction.

Abstract: The present invention relates to a process for the treatment of a hydrocarbon charge by high temperature ultrafiltration, said process comprising the steps of circulating said charge in a module comprising at least one mineral ultrafiltration barrier coated with a sensitive mineral layer of at least one metal oxide and of operating at a temperature higher than 100.degree. C. The barrier, which preferably has a ceramic or metallic support, is coated with a sensitive layer selected from the group comprising titanium dioxide, magnesium oxide, aluminium oxide, spinel MgAl.sub.2 O.sub.4, silica. The invention is applicable to the regeneration of a waste oil and to the reduction of the rate of asphaltenes in a hydrocarbon charge.

Abstract: The invention concerns a process for the removal of catalyst residues from a gas by contacting the gas with particulate mineral oxides. The process of the invention may be applied to the removal of coordination catalyst residues from .alpha.-olefins recycled from a polymerization reactor. The process is particularly useful in the removal of alkylaluminium halides and hydrogen halides, such as diethylaluminium chloride and hydrogen chloride, from .alpha.-olefins such as propylene. The process offers the advantages of being able to be operated under anhydrous conditions, and combining high efficiency in the removal of low levels of catalyst residues with a high capacity for the catalyst residues.

Abstract: A palladium or palladium alloy hydrogen diffusion membrane which has been treated with silane and/or silicon tetrafluoride is employed to separate hydrogen from a hydrocarbon with which it is in admixture and from which it may have been produced under dehydrogenation conditions in the presence of said membrane.

Abstract: Disclosed is a process for the polymerization of olefins wherein olefinic compounds are separated from mixtures containing them with resulting improved utilization of olefinic compounds. Such olefinic compounds are separated by use of membrane separation units and can be recycled to a polymerization zone.

Abstract: This invention relates to an improved process for the alkylation of olefins in an alkylation unit feed stream in order to produce a higher yield of alkylate having a higher octane number, a lower acid consumption rate, and a lower energy consumption. Such a process involves passing a feed stream comprised of olefins and paraffins through a membrane so that the olefins are separated from the paraffins. In passing through the membrane, the olefins are facilitated in their transport by an isoparaffin sweep stream and together, the olefin/isoparaffin stream is passed into an alkylation reactor. Within the reactor, the olefins react with the isoparaffins to form alkylate.