Abstract: Thin film membranes of polyurea, polyureapolyurethane alloy, polyurea-polyurea/urethane alloy or polyurea/urethane are prepared by deposition of a thin film of suspension of the selected polymer on a thick permeable support layer by the technique of preparing a suspension of the selected polymer in a solvent which does not dissolve the thick permeable support layer and permitting the solvent to evaporate and/or permeate through the thick-permeable layer.

Abstract: The ability of cellulose membranes to separate solutes from solvents under reverse osmosis conditions is significantly improved by subjecting the membrane prior to use to several cycles of drying and rewetting.

Abstract: Regenerated cellulose membranes used for the separation of organic liquids, for example, ketone dewaxing solvents from dewaxed oil or NMP extraction solvents from extract, have their solute rejection capability enhanced by chemical modification by contacting said membrane with a bifunctional reagent that is reactive with the hydroxy groups in the anhydroglucose units of the regenerated cellulose polymer. The reaction of the bifunctional reagent with the hydroxy groups in the polymer results in the crosslinking of the polymer which, in turn, results in the improvement of the membrane's selectivity in organic liquid separations applications.

Abstract: Basic nitrogen compounds (BNC) are selectively removed from solvent extracted oils by adsorption of said BNC's by solid acidic polar adsorbents. The oils are extracted using any of the common extraction solvents, such as furfural, phenol, SO.sub.2, N-methyl-2-pyrrolidone (NMP), preferably NMP. The resulting raffinate, which contains the desirable oil fraction, has the BNC's present therein removed by adsorption thereof onto an adsorbent, characterized as being a solid, polar acidic adsorbent, exemplified by silica-alumina, a high alumina base amorphous cracking catalyst (such as manufactured by Ketjen/Akzo) and crystalline zeolite (such as H-Y zeolites) are effective adsorbents. The adsorbents may additionally contain fluorine or may contain up to 30 weight percent water. The adsorbents are regenerated by either purging with hydrogen at elevated temperature and pressure, or by washing the BNC saturated adsorbent with extraction process extraction solvent, such as NMP.

Abstract: Thin film composite membranes comprising a thin active selective layer deposited from a solution onto a thicker porous non-selective support layer are disclosed. In particular, a thin film of polyurea/urethane is coated onto a microporous support substrate from a specific multi-component solvent system. Effective film thicknesses of less than 1 micron can be achieved, said thin films being virtually defect free. Asymmetric-composite membranes consisting of a thin active layer of polyurea/urethane on a microporous support substrate are useful for separating aromatics from saturates, especially under pervaporation or perstraction conditions.

Abstract: Dewaxing aids used to assist in the solvent dewaxing of waxy hydrocarbon oils are recovered from the dewaxed oil or waxy precipitate, or both, by selective permeation of the oil or wax through a perm-selective polyimide ultrafiltration membrane, under ultrafiltration conditions, leaving a retentate of dewaxing aid, or reduced oil and/or wax content, which dewaxing aid-rich retentate can be recycled to the solvent dewaxing process.

Abstract: N-methyl pyrrolidone solvent (hereinafter NMP) used to extract aromatic components from lubricating oil distillates is purified by contacting the solvent with activated alumina.

Abstract: Volatile acids present in n-methyl pyrrolidone vapor from solvent extraction processes can be reacted with sacrificial metals such as magnesium to concentrate the acid salts into a small volume of oil/NMP. Steam stripping removes NMP from the oil/NMP mixture while simultaneously springing a portion of the light carboxylic acids from their salts, the acids going with the NMP. This condensed NMP stream containing the light carboxylic acids is contacted with an ion exchange resin which removes the acids from the NMP. The purified small volume of NMP is returned to the extraction process.

Abstract: An anisotropic elastomeric membrane preferably made from polyurea/urethane has been prepared. These anisotropic membranes are made from the corresponding polymeric material by preparing the polymeric material in a good solvent containing less than 5 vol % non-solvent, producing a film of the polymer solution on a support with a maximum pore size less than 20 microns, subjecting the film to conditions such that the solvent vapor pressure-time factor is 1000 mm Hg-min. or less, preferably 200 mm Hg-min or less, most preferably approaching 0 mm Hg-min and quenching the membrane film in a non-solvent yielding a three-layered anisotropic membrane.

Abstract: For removing haze from dewaxed hydrocarbon oil mixture boiling in the lubricating oil range which is hazy, the hazy oil mixture is filtered in the filtration stage (201) of a dewaxing plant which is concurrently filtering undewaxed hydrocarbon oil mixture boiling in the lubricating oil range. Prior to filtering, the hazy dewaxed oil mixture is subjected to pretreatment (in pretreatment stage 204) such as to promote removal of haze from the dewaxed oil mixture during filtering. This pretreatment is carried out independently of the undewaxed oil mixture and can involve dilution/chilling with an oil solvent (e.g. liquid propane) and/or introduction of free excess electric charge, for example by charge injection. As an alternative to the pretreatment, the temperature conditions under which filtration takes place may be low enough to promote wax crystallization.

Abstract: Waxy oil distillates, preferably waxy petroleum oil distillates, most preferably waxy lube refrigerator, turbine, transformer or other speciality oil distillates which contain appreciable amounts of aromatics and polar molecule contaminants can have wax and aromatics/polars simultaneously and continuously removed from said oil using an adsorbent/desorbent system. The adsorbent system employs a combination of large pore polar adsorbent/hydrophobic molecular sieves. The desorbent system utilizes a combination small diameter polar solvent/large diameter non-polar solvent to regenerate the loaded adsorbent.

Abstract: Aromatic hydrocarbons present in a hydrocarbon feed stream containing a mixture of aromatic hydrocarbons and non-aromatic saturated organic components are separated from said hydrocarbon feed stream by selective permeation of the aromatic hydrocarbon through a regenerated cellulose or cellulose acetate membrane which has been impregnated with polyethylene glycol. The thus treated membrane possesses high selectivity for aromatic hydrocarbons at a high flux. The amount and type of polyethylene glycol impregnated into the membrane is carefully controlled in order to achieve high aromatic selectivity and high flux.

Abstract: Naphtha is isomerized using a medium-pore zeolite catalyst.Isomerization is accomplished by contacting the hydrocarbon with the medium-pore zeolite catalyst at a temperature in the range 200.degree. to 400.degree. C., preferably, at a space velocity of 0.05 to 75 v/v/hr, preferably, at a pressure at 14.7 to 1500 psig.The medium zeolite catalyst employed has a silica to alumina ratio in the range of about 5 to >30, preferably 10-20, more preferably 12-17 and a pore size of about 5.5 to 6.8 .ANG.. The preferred medium pore zeolite is a zeolite of the offretite type. The zeolite preferably has associated with it a hydrogenation component which is typically a Group VIII metal, oxide or sulphide, or mixtures thereof, preferably platinum or palladium. The preferred offretite type zeolite may be any of the readily available commercial materials and may have their SiO.sub.2 /Al.sub.2 O.sub.

Abstract: Solvent dewaxing of waxy hydrocarbon oils is improved by using a poly (n-C.sub.24) alkyl methacrylate polymer dewaxing aid in combination with lower melting point weight poly (C.sub.8 -C.sub.20) alkyl methacrylate polymer dewaxing aids. The solvent dewaxing processes improved using this combination dewaxing aid are the incremental and total predilution solvent type processes employing either surface chilled indirect heat exchanger means or direct chilling using cold solvent.The solvent dewaxing processes are those employing normally liquid dewaxing solvents, as exemplified by C.sub.3 -C.sub.6 ketones, such as methyl ethyl ketone, methyl isobutyl ketone and mixtures thereof, mixtures of ketones with aromatic such as MEK/toluene, halogenated C.sub.2 -C.sub.4 hydrocarbons such as tetrachloraethane, trichloro ethylene, etc.

Abstract: The filtration performance of a slurry containing crystallized wax, dewaxed oil and dewaxing solvent is improved by use of an agitator means which possesses a characteristic dimension which when divided by the average wax crystal diameter yields a dimensionless number of about 1,500 or less, preferably about 1,000 or less, more preferably about 500 or less, most preferably about 250 or less. Use of an agitator means which possesses a characteristic dimension yielding a dimensionless number in the range recited above causes a reduction in the size of the vortex generated as the agitator means passes through the slurry during chilling. As a consequence, more intimate contacting of the wax particles during chilling is promoted.The needed characteristic dimension of the agitator may be obtained in any number of equally acceptable ways. Single large agitator blades can be replaced by more numerous smaller blades; large blades can be perforated, notched, etc.

Abstract: Polycarbonate membranes are prepared for the selective separation of organic liquid mixtures, especially for the separation of ketone dewaxing solvents from dewaxed oil by preshrinking said membranes in presence of a class of solvents of solubility parameter values in the range of from 8.9 to 10 (cal/cm.sup.3).sup.0.5, and which do not dissolve the membranes.Preshrunk polycarbonate membranes, prepared by the method of the present invention, can be used for the selective separation of the various components in organic liquid mixtures such as, for the separation of dewaxing solvents from dewaxed oil, preferably the separation of ketone dewaxing solvents from dewaxed oil. The separation is based on a reverse osmosis technique whereby the solvent is permeated through the membrane under an applied pressure sufficient to overcome the osmotic pressure of the system. Applied pressures can vary from 50 up to 1,500 psi, depending on solution concentration. The separation can be carried out in the temperature range -30.

Abstract: Wax crystals of improved morphology are produced by employing a dewaxing aid in an agitated solvent dewaxing environment, preferably an agitated indirect chilling solvent dewaxing environment, such as an agitated chiller, such as a scraped surface chiller which has been modified so that the scraper is not in contact with the internal wall of the chiller wherein a high degree of agitation is maintained by rotating the paddles to achieve a paddle tip speed of 25 to 400 ft./min. and the gap between the agitator tip and the inner wall of the vessel is about 0.5 to 40% of the internal diameter of the chiller. Agitation in agitated indirect chiller appratus has been shown to produce significantly improved feed filter rates and liquids/solids ratios when employed in conjunction with dewaxing aids in solvent dewaxing processes.

Abstract: It has been discovered that cellulose acetate membranes, fabricated using nonaqueous solvent systems, can be used for the separation of polar solvents, especially ketone dewaxing solvents from dewaxed oil. The cellulose acetate membranes so prepared are of a reduced acetyl content and exhibit very good resistance to ketone solvents. The specific fabrication procedure avoids exposing the cellulose acetate to even transient mixtures of ketone and alcohol or ketone and water. Although the cellulose acetate polymer is insoluble in pure water, alcohol, or ketone it is soluble in mixtures of ketone-alcohol and ketone-water.The resulting membrane is an effective means for separating ketone dewaxing solvent from dewaxed oil.

Abstract: A process in fuels production for increasing the yield of deasphalted oil production from upgraded residua and improving deasphalter operability involving mixing the upgraded residua with an aromatics solubilizing aid to prevent the formation of an immiscible third phase during deasphalting.

Abstract: This invention relates to a method for catalytically manufacturing a low pour point petroleum product from distillates of crude oil, and more particularly to a method for economically manufacturing a low pour point petroleum product, such as the insulating oil, the lubricating oil used for various types of freezing devices, or the base oil for such lubricating oil, from a paraffin-based crude oil as the starting material without using any special rare crude oil such as naphthene-based crude oil. The catalyst comprises zeolite TSZ.