Abstract: A Method for cleaning degraded oil comprising oil-soluble degradation products and a system for implementing the method are disclosed. The method comprises the steps of receiving an inlet flow (1, 1a, 1b) of degraded oil, precipitating oil-soluble degradation products from the degraded oil by cooling the degraded oil, passing the cooled degraded oil as a filtration flow (3, 3a, 3b) through a filter (104, 204, 304) so as to retain the precipitated degradation products in the filter, and discharging an outlet flow (2, 2a, 2b) of cleaned oil.

Abstract: Base stocks having Group III/III+ characteristics are prepared from certain advantageous crude oils via simplified process configurations and/or under less severe process conditions. Crude oils comprising a vacuum gas oil (VGO) fraction having a ratio of a sum of paraffin content plus 1-Ring species content to multi-ring species content that is greater than or equal to about 1.5 are advantageous in this context. Other parameters such as API gravity and crude compositional ranges may also be considered for identifying advantageous crudes. In some instances, advantageous crudes are processed into Group III base stocks via a process configuration in which the crude oil is directly supplied to a hydroprocessing unit.

Abstract: The present invention relates to a method for fractionating a crude mixture comprising at least one oil and at least one wax, which comprises the following method steps: (a) carrying out a pre-fractionation stage as a layer crystallization (i) with a crude mixture comprising at least one oil and at least one wax or (ii) with a crude solvent mixture obtained by adding prior to the pre-fractionation stage at most 100% by weight of solvent relative to the weight of the crude mixture, to prepare a first fraction containing low waxy oil and a second fraction containing low oily wax, (b) carrying out a first crystallization stage including (b1) a first suspension crystallization sub-stage with the first fraction containing low waxy oil to prepare a third fraction containing dewaxed oil and a fourth fraction and (b2) after the first suspension crystallization sub-stage, a second suspension crystallization sub-stage with a mixture of the fourth fraction obtained in method step (b1) and the second fraction containing

Abstract: The determination of wax crystal particle size and population is used to monitor the performance of wax crystallizers used in lubricant oil processing using solvent dewaxing. The wax crystal particle size is monitored using online measurements. The information obtained from on-line monitoring is then used to control crystallization in the dewaxing equipment in order to optimize performance of the dewaxing units.

Abstract: A process to prepare a base oil starting from a slack wax containing feedstock by (a) contacting the feedstock in the presence of hydrogen with a sulphided hydrodesulphurisation catalyst having nickel and tungsten on an acid amorphous silica-alumina carrier and (b) performing a pour point reducing step on the effluent of step (a) to obtain the base oil.

Abstract: A method of refining a petroleum product to remove aromatics and to separate paraffinic oils and waxes is provided. The method involves the utilization of phase equilibria wherein crystallized or solidified waxes, normally present in the petroleum product, are used to remove oils from a liquid solvent phase containing dissolved aromatics present in the unrefined petroleum product. The wax containing the oils is separated from the aromatic-containing solvent and is further processed to separate the waxes and oils. For petroleum products containing little, if any, wax, additional wax may be added and recycled back for further use in removing oils from the petroleum product. The method has particular application in preparing lubricating oils having a high viscosity index, where the presence of aromatics and wax can be detrimental.

Abstract: A laser beam reflected by wax crystals is used in determining the wax crystallization temperature of a hot dewaxing solvent upstream of solvent chillers. This is automatically achieved by an on-line method from a remote control point, in which a slipstream of solvent is passed through an attached solvent loop into a sample chamber in the loop, without being exposed to ambient conditions. As the sample is cooled, the beam reflections are detected and indicate the wax to crystallization temperature. Corrective measures can then be taken to prevent fouling of the chillers, if need be.

Abstract: A process to prepare a base oil starting from a slack wax containing feedstock by (a) contacting the feedstock in the presence of hydrogen with a sulphided hydrodesulphurisation catalyst having nickel and tungsten on an acid amorphous silica-alumina carrier and (b) performing a pour point reducing step on the effluent of step (a) to obtain the base oil.

Abstract: A process for treating nitrogen-containing, substantially paraffinic product derived from a Fischer-Tropsch process. The substantially paraffinic product is purified in a purification process to lower the concentration of oxygen, nitrogen, and other impurities. The nitrogen content of the purified product is monitored, and the conditions of the purification step are adjusted to increase nitrogen removal if the nitrogen content of the purified product exceeds a preselected value.

Abstract: A method of refining a petroleum product to remove aromatics and to separate paraffinic oils and waxes is provided. The method involves the utilization of phase equilibria wherein crystallized or solidified waxes, normally present in the petroleum product, are used to remove oils from a liquid solvent phase containing dissolved aromatics present in the unrefined petroleum product. The wax containing the oils is separated from the aromatic-containing solvent and is further processed to separate the waxes and oils. For petroleum products containing little, if any, wax, additional wax may be added and recycled back for further use in removing oils from the petroleum product. The method has particular application in preparing lubricating oils having a high viscosity index, where the presence of aromatics and wax can be detrimental.

Abstract: A method of refining a petroleum product to remove aromatics and to separate paraffinic oils and waxes is provided. The method involves the utilization of phase equilibria wherein crystallized or solidified waxes, normally present in the petroleum product, are used to remove oils from a liquid solvent phase containing dissolved aromatics present in the unrefined petroleum product. The wax containing the oils is separated from the aromatic-containing solvent and is further processed to separate the waxes and oils. For petroleum products containing little, if any, wax, additional wax may be added and recycled back for further use in removing oils from the petroleum product. The method has particular application in preparing lubricating oils having a high viscosity index, where the presence of aromatics and wax can be detrimental.

Abstract: A method for producing a process oil is provided in which an aromatic extract oil is added to a paraffinic rich feed to provide a blended feed. The blended feed is then hydrotreated in a first hydrotreating stage to convert at least a portion of sulfur and nitrogen in the feed to hydrogen sulfide and ammonia. After stripping, the feed is subjected to a second hydrotreating stage to provide a process oil.

Abstract: A method and apparatus for continuously removing oil from oil-bearing solids such as tar sands, vegetables or other solid materials using a solvent is provided. By providing a pressure differential between the exterior and interior of an oil extraction chamber, substantially oil free solids may be removed from the oil extraction chamber through a solids extraction channel without removing any substantial volume of solvent through the solids extraction channel.

Abstract: A process for producing a high VI/low volatility lubricating oil basestock. The process comprises subjecting the raffinate from a solvent extraction step to a two step, single stage hydroconversion process wherein the first step involves severe hydroconversion of the raffinate followed by a cold hydrofinishing step.

Abstract: A process for producing a high VI/low volatility lubricating oil basestock. The process comprises subjecting the raffinate from a solvent extraction step to a two-step, single-stage hydroconversion process wherein the first step involves severe hydroconversion of the raffinate followed by a cold hydrofinishing step. The effluent from the cold hydrofinishing step is then catalytically dewaxed or in the alternative, solvent dewaxed followed by catalytic dewaxing.

Abstract: A process for upgrading a wax-containing feedstock to produce a wax and a high VI/low volatility lubricating oil basestock. The process comprises subjecting the raffinate from a solvent extraction step to a two step, single stage hydroconversion process wherein the first step involves severe hydroconversion of the raffinate followed by a cold hydrofinishing step.

Abstract: The wax-containing hydrocarbon feedstocks are pre-treated by contacting them with a homogeneous solution containing 1-5 vol. % of an acid diluted in an alcohol/water mixture (preferably containing 60-90 vol. % alcohol). The pre-treated feedstock is then contacted, in the presence of hydrogen, with at least two catalysts in sequence and with no intermediate separation, comprising at least one hydrodewaxing catalyst and one hydrocracking catalyst, to recover high-grade middle distillates.

Abstract: A semicontinuous process for solvent dewaxing a waxy petroleum oil feed stream including the steps of: diluting of the waxy oil feed stream with solvent; feeding cold oil/solvent/wax mixture to a filter to remove the wax and obtain an oil/solvent filtrate stream; contacting the oil/solvent filtrate stream with a selective semipermeable membrane to selectively transfer solvent through the membrane to obtain a solvent-rich permeate; and periodically directing a warm stream of recovered solvent onto the membrane surface to wash the membrane and remove impurities therefrom.

Abstract: A process for solvent dewaxing petroleum feedstock to separate crystallized wax from lubricant oil by filtration of a wax/oil/solvent mixture. The feedstock is sequentially cooled and mixed with cold polar solvent to form a wax crystal phase and oil-solvent phase, and-the oil-solvent filtrate stream is contacted with solvent permeable selective membrane at low temperature to recover an internal circulating permeate solvent stream and an oil-rich retentate stream containing dewaxed oil product and residual solvent. Improved operation is achieved by splitting the internal circulating solvent stream into a multiple cold solvent recycle streams and injecting a plurality of the cold solvent recycle streams into the waxy petroleum feedstock during sequential cooling and mixing. By initially injecting a cold recycle solvent stream in to the waxy petroleum feedstock at a small temperature differential near the wax crystallization temperature, shock cooling and excess small wax crystal formation is avoided.

Abstract: A process for solvent dewaxing a waxy oil feed to obtain petroleum oil lubricating stock comprising the steps of contacting a warm waxy oil feed by indirect heat exchange first with cold filtrate, then with refrigerant to crystallize and precipitate the wax in the oil feed to form an oil/solvent/wax mixture. The oil/solvent/wax mixture is diluted with cold solvent to adjust the viscosity of the mixture and the mixture is fed to a filter which filters and removes the wax from the cold oil/solvent/wax mixture. A cold wax cake is recovered and a cold oil/solvent filtrate stream is recovered. The cold oil/solvent filtrate stream is fed, at the filtration temperature, to a selective permeable membrane. The membrane selectively separates the cold filtrate into a cold solvent permeate stream and a cold filtrate stream which contains the dewaxed oil and the remaining solvent. The cold solvent permeate stream at the filtration temperature is recycled to the filter feed stream.

Abstract: A process for solvent dewaxing a waxy oil feed to produce a lubricating oil by contacting a warm waxy oil feed in counter-current with a cold oil/solvent filtrate stream through a selectively permeable membrane to transfer cold solvent through the membrane to the feed and simultaneously cool the feed, dilute it with solvent and separate solvent from the cold oil/solvent filtrate stream. The cooled, diluted feed stream is then further cooled to precipitate the wax to form an oil/solvent/wax mixture which is further diluted with cold solvent and filtered to remove wax. The cold oil/solvent filtrate stream is cycled to the selectively permeable membrane for the counter-current contact with the warm waxy oil feed and, after removal of a portion of the solvent over the membrane, is sent to an oil/solvent separation operation in which the solvent is removed from the dewaxed oil.

Abstract: A method (and apparatus) is disclosed for the spectroscopic determination of the amount .alpha..sub.Nn of one constituent N of a fluid mixture 0 in another constituent n of the mixture, following separation of the mixture into its constituents 1,..., M (where n, N.ltoreq.M). The method involves determining the absorptivities an (n=1,...,N) of the M constituents from spectroscopic measurements and computing the amount .alpha..sub.Nn from a mathematical expression containing the absorptivities a.sub.n and a.sub.N which are expressed or expressible as the quotient a.sub.n /a.sub.N only. The method is insensitive to changes in the absorptivities due to feed variability or changes in upstream process conditions, since any changes in the numerator and denominator of the quotient used are affected correspondingly. A modification to the method involves determining the content .alpha..sub.N0 of constituent N in feed 0 from a mathematical expression containing a.sub.0, where a.sub.

Abstract: This invention relates to a process of dewaxing a hydrocarbon oil involving the steps of separating and precipitating the wax component of the hydrocarbon oil. This process is facilitated by incorporating into the oil a linear polymer of carbon monoxide with one or more olefins comprising .alpha.-olefins with at least 10 carbon atoms per molecule (C.sub.10+ .alpha.-olefins) wherein in this polymer monomer units of carbon monoxide and olefins are present in a substantially alternating arrangement. Optionally, the process may also involve the use of a polymer of one or more olefinically unsaturated compound comprising of alkyl acrylates or alkyl methacrylates with at least 8 carbon atoms in the alkyl group (C.sub.8+ alkyl esters). The process may be practiced using the single-stage or multi-stage dilution method.

Abstract: Lubricating base oils having a high viscosity index, preferably at least 135, are manufactured by catalytic hydroisomerization of a hydrocarbonaceous feedstock, derived from a waxy crude oil, which feedstock has not been treated to remove a lubricating base oil fraction and which feedstock contains at least 30% by weight wax and has at least 80% by weight boiling above 300.degree. C. and at most 30% by weight boiling above 540.degree. C.

Abstract: A method is disclosed for reducing the cloud point of materials comprising the steps of chilling the waxy oil so as to achieve submicron crystallization followed by ultrafiltration thereby effecting separation of a permeate of reduced cloud point from a retentate. Chilling to produce submicron crystallization is to a temperature about 3.degree. C. or less above the cloud point of the material, preferably from 0.5.degree. to 2.degree. C. above the cloud point of the material, most preferably between 1.degree. to 2.degree. C. above the cloud point of the material. In general any mixture, solution or melt containing components which crystallize at different temperatures can be separated by this procedure. The method is especially useful for reducing the cloud point of waxy hydrocarbon oils.

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: Copolymers of dialkyl fumarate and vinyl acetate having Specific Viscosities of at least 2.5 at 2% polymer concentration in xylene at 40.degree. C., and wherein at least 50 wt. % of said alkyl groups are C.sub.20 to C.sub.24, are useful as dewaxing aids, particularly in propane dewaxing.

Abstract: A solvent dewaxing process is described comprising mixing a waxy hydrocarbon oil, preferably a waxy petroleum oil, most preferably a waxy lube or specialties oil, with dewaxing solvent and a dewaxing aid comprising (A) a dialkylfumarate-vinyl laurate copolymer and (B) a wax-naphthalene condensation copolymer, a dialkyl fumarate-vinyl acetate copolymer or an ethylene vinyl acetate copolymer and chilling the mixture to yield a slurry comprising solid particles of precipitated wax and a solution of dewaxed oil and solvent and separating said solid wax from dewaxed oil solution.

Abstract: Refined waxes and dewaxed lubricating oil basestocks are simultaneously produced in a reversed deoiling-dewaxing process employing conventional dewaxing solvents and existing process equipment. Improved yields, lower solvent useage, and higher throughputs are achieved using dewaxing aids in the final stage. Waxy hydrocarbon oils are solvent dewaxed to a temperature which produces a low oil content refined high melting point hard wax product which is recovered, e.g. by filtration. The hard wax product can be deoiled. The filtrate from the initial dewaxing operation is then injected with dewaxing aid and further chilled in secondary chiller means such as scraped surface chillers to a lower temperature to produce more deeply dewaxed oil and a low melting point soft wax product which are separated e.g. by filtration. The low melting point wax is desolvated and the dewaxing aid may be recovered for example by passing the wax through a membrane or by distillation.

Abstract: An improved method for separating a slack wax into a wax fraction and a lube oil fraction is disclosed. The method comprises passing the slack wax into a first mixing zone and subsequently into a second mixing zone. Solvent selectively miscible with the lube oil fraction is added to the zones. The temperature of the solvent added to the second mixing zone is substantially higher than the temperature of the solvent added to the first mixing zone. This process produces a wax fraction having a relatively low lube oil content.

Abstract: A warm-up deoiling process for lube oil slack wax wherein cold slack wax from a solvent dewaxing operation is warmed up and mixed with solvent to dissolve foots oil contained therein and passed to a rotary drum filter to recover solid wax and a filtrate comprising a solution of foots oil and solvent wherein said filtrate is contacted with one side of a semi-permeable membrane made from regenerated cellulose which selectivity permeates at least a portion of solvent through said membrane and recycling the permeated solvent directly back into the warm-up deoiling operation as part of the solvent mixed with the slack wax.

Abstract: In solvent deoiling of slack waxes utilizing conventional multi-stage, scraped chillers, solvent is injected into conduits transporting slack wax slurry from one scraped chiller to the next through high velocity jet nozzles.

Abstract: Improvements in processes for stripping solvent from dewaxed oils and deoiled waxes; the use of an inert gas (such as nitrogen) as a stripping agent for removing solvent from dewaxed oils, deoiled waxes and slack waxes resultant from solvent dewaxing processes.

Abstract: Ketone dewaxing solvent is separated and recovered from dewaxed oil and a wax slurry through the use of flash vaporization or distillation followed by steam stripping. Water is removed from the recovered solvent through the use of a combination of a decanting drum to form a solvent phase and a water phase, a deketonizer tower which strips solvent from the water phase, and a simple distillation tower which functions as a solvent dehydrator. It has been found that feeding a portion of the overhead vapors from the flash vaporization step directly to the bottom of the dehydrator provides enough heat to eliminate the need for a reboiler on the dehydrator tower.