Abstract: A high temperature paraffinic froth treatment (HTPFT) process utilizes an unheated flash vessel as a first stage of solvent recovery in a paraffinic solvent recovery unit (PSRU) to minimize asphaltene precipitation and fouling in subsequent stages of solvent recovery. The HTPFT may utilize a heat pump circuit for heat integration in the PSRU where a first stage of solvent recovery is at a lower temperature than a second stage of solvent recovery. Froth entering froth separation vessels can be heated using heat in a tailings stream using a heat pump. Froth separation vessels used to separate froth for collecting a bitumen-containing overflow utilize a collector pot and conventional feedwell combination, or a combination of a collection ring and nozzle arrangement for reducing disturbance in the vessel and improving collection of the overflow.

Abstract: A separation method and a separation apparatus for a solvent extracted by supercritical extraction. The separation method increases a solvent recovery rate by minimizing the amount of a solvent to be evaporated and lost since the pressure of a solvent is reduced by arranging two or more separators in series. The method includes: introducing a fluid having passed through a supercritical extractor into a first flash vessel; introducing the fluid which has passed through the first flash vessel into a second flash vessel; and discharging and recovering the carbon dioxide and the solvent which have passed through the second flash vessel, respectively. The pressure of the first flash vessel is 40-100 bar, and the pressure of the second flash vessel is 1-30 bar. The fluid includes carbon dioxide and a solvent.

Abstract: Co-feeding sulfolane into a transalkylation reactor along with the aromatic hydrocarbon feed(s) can improve benzene purity of the benzene product stream produced from the transalkylation product mixture, especially at the beginning phase of a catalyst cycle.

Abstract: The present disclosure relates to a composition for reducing aromatics from a hydrocarbon feedstock. The composition comprises a solvent mixture. The solvent mixture includes a primary solvent, a first co-solvent, a second co-solvent, and a secondary solvent. The present disclosure also relates to a process for reducing aromatics from a hydrocarbon feedstock.

Abstract: A steam reboiler unit that includes turbines for reducing the pressure of various streams associated with the reboilers. The turbines generate electricity from the pressure reduction which can be recovered and utilized elsewhere in the processing unit. Data from the turbine associated with the amount of electrical power generated by the turbine is used to adjust other processing conditions to provide for a more efficient operation of the processing unit.

Abstract: The present invention relates to an improved process for manufacturing a purified aqueous hydrogen peroxide solution. The invention further relates to a plant for producing hydrogen peroxide in which the improved process for manufacturing a purified aqueous hydrogen peroxide solution according to the present invention is employed.

Abstract: A process for producing aromatics from a hydrocarbon source in the presence of supercritical water comprising the steps of mixing a pressurized, pre-heated water stream with a pressurized, pre-heated petroleum feedstock, the pressurized, pre-heated water stream at a pressure above the critical pressure of water and a temperature above the critical temperature of water, feeding the combined stream to a supercritical water reactor to create a modified stream, cooling and depressurizing the modified stream, separating the depressurized stream in a vapor-liquid separator, condensing the vapor stream, separating the condensed stream into a water recovery stream and a light product recovery stream, extracting the aromatics from the light product recovery stream, depressurizing the liquid stream, separating the depressurized liquid stream in a heavy separator into an upgraded product stream, and recycling part of the upgraded product stream to the pressurized, pre-heated petroleum feedstock as a product recycle.

Abstract: One exemplary embodiment can be a process. The process can include contacting one or more contaminated hydrocarbons with a hydrogen gas stream in a flash feed separator to generate a first liquid stream, stripping the first liquid stream to generate a residue stream, and separating the residue stream in a film generating evaporator to obtain a recovered distillate.

Abstract: The invention relates to a process for coal conversion, optionally in co-processing with other feedstocks, notably of the biomass type, comprising at least one liquefaction step, followed by a fixed-bed hydrocracking step and a catalytic reforming step. With this process, aromatic compounds can be obtained from a feedstock containing coal.

Abstract: Certain embodiments of the invention provide an apparatus for separating aromatic hydrocarbons from an aromatic hydrocarbon feed stream. The apparatus includes a membrane support, and a hydrophilic polymer membrane matrix disposed on the membrane support. The hydrophilic polymer membrane matrix includes an effective amount of polyvinyl alcohol and an effective amount of sodium alginate. The apparatus further includes a carrier agent bonded to the hydrophilic polymer membrane matrix using a cross-linking agent. The carrier agent exhibits a greater affinity for aromatics compared to aliphatics. The apparatus further includes a membrane housing configured to hold the membrane support. The membrane housing includes an inlet, a permeate outlet, and a retentate outlet, the inlet being operable to receive the aromatic hydrocarbon feed stream, the permeate outlet being operable to discharge a permeate stream, and the retentate outlet being operable to discharge a retentate stream.

Abstract: The invention is directed to a process for cleaning bitumen froth by mixing a sufficient amount of naphtha with the bitumen froth to provide a naphtha-to-bitumen ratio within the range of about 4.0 (w/w) to about 10.0 (w/w) and separating substantially dry diluted bitumen from the water and solids. Also provided is a process for cleaning diluted bitumen by mixing a sufficient amount of naphtha with the diluted bitumen to provide a naphtha-to-bitumen ratio equal to or greater than about 1.8 (w/w) and separating marketable fungible raw bitumen from the water and solids.

Abstract: A method for processing froth treatment tailings, including separating the froth treatment tailings in order to produce a coarse mineral material fraction and a fine mineral material fraction therefrom, subjecting the coarse mineral material fraction to froth flotation in order to produce a heavy mineral concentrate and a coarse mineral material tailings therefrom, and subjecting the heavy mineral concentrate to solvent extraction in order to produce a debitumenized heavy mineral concentrate and a bitumen extract therefrom.

Abstract: A process and composition for removing heavy oil and bitumen from oil sands is disclosed. The composition comprises an emulsion of d-limonene in water, with an optional anionic surfactant as an emulsifying agent. The emulsion is contacted with an oil sand slurry until the aqueous and hydrocarbon phases separate. The process may take place at temperatures less than about 80° C. and with low concentrations of the d-limonene.

Abstract: Embodiments of a method and a system for recovering energy, materials or both from asphaltene-containing tailings are disclosed. The asphaltene-containing tailings can be generated, for example, from a process for recovering hydrocarbons from oil sand. Embodiments of the method can include a flotation separation and a hydrophobic agglomeration separation. Flotation can be used to separate the asphaltene-containing tailings into an asphaltene-rich froth and an asphaltene-depleted aqueous phase. The asphaltene-rich froth, or an asphaltene-rich slurry formed from the asphaltene-rich froth, then can be separated into a heavy mineral concentrate and a light tailings. Hydrophobic agglomeration can be used to recover an asphaltene concentrate from the light tailings. Another flotation separation can be included to remove sulfur-containing minerals from the heavy mineral concentrate. Oxygen-containing minerals also can be recovered from the heavy mineral concentrate.

Abstract: Solvent regeneration to recover a polar hydrocarbon (HC) selective solvent substantially free of hydrocarbons (HCs) and other impurities from a solvent-rich stream containing selective solvent, heavy HCs, and polymeric materials (PMs) generated from reactions among thermally decomposed or oxidized solvent, heavy HCs, and additives is provided. A combination of displacement agent and associated co-displacement agent squeezes out the heavy HCs and PMs from the extractive solvent within a solvent clean-up zone. Simultaneously, a filter equipped with a magnetic field is positioned in a lean solvent circulation line to remove paramagnetic contaminants. The presence of the co-displacement agent significantly enhances the capability of the displacement agent in removing the heavy HCs and PMs from the extractive solvent.

Abstract: The present invention relates to a process for recovering polar hydrocarbons from non-polar hydrocarbons, such as aromatics from non-aromatics, naphthenes from paraffins and isoparaffins, or olefins from paraffins and isoparaffins, in feed mixtures containing at least a measurable amount of heavier hydrocarbons. According to the invention, an improved extractive distillation (extractive-distillation) process is disclosed for recovering aromatic hydrocarbons including benzene, toluene, and xylenes from heavy (C9+) hydrocarbons. The invention also relates to an improved extractive-distillation process for recovering mainly benzene and toluene from the C6-C7 petroleum streams containing at least a measurable amount of C8+ hydrocarbons.

Abstract: A device and a method for separating mixtures that contain oil or bitumen and additives. The device and the method are applicable in particular to separating stone chippings and bitumen in excavated asphalt road surfaces. In the case of oil sands and oil shale, a mineral phase can be separated from an oil phase and separation of bitumen and carrier felt can be induced in recycling of bitumen felt, oil binder and oil. The individual components of the mixture are separated from one another using a solvent, wherein the solvent takes up the oil or bitumen. The oil and bitumen are subsequently separated from the solvent so that the solvent can be reused.

Abstract: An improved solvent regeneration system for extractive distillation and liquid-liquid extraction processes capable of effectively removing heavy hydrocarbons and polymeric materials that otherwise develop in a closed solvent loop. The improved process employs a light hydrocarbon displacement agent, which is at least partially soluble in the solvent to squeeze the heavy hydrocarbons and polymeric materials out of the solvent, with virtually no additional energy requirement. It has been demonstrated that the light non-aromatic hydrocarbons in the raffinate stream generated from the extractive distillation or the liquid-liquid extractive process for aromatic hydrocarbons recovery can displace not only the heavy non-aromatic hydrocarbons but also the heavy aromatic hydrocarbons from the extractive solvent, especially when the aromatic hydrocarbons in the solvent are in the C10+ molecular weight range.

Abstract: A tailings solvent recovery vessel substantially without conventional internals utilizes nozzles for forming very fine solvent-containing hydrocarbon droplets from a solvent-containing tailings feedstream. The hydrocarbon droplets are discrete from water droplets. The hydrocarbon droplets are small enough to result in a large surface area and a desired fall residence time but sufficiently large that they are not entrained with the rising vapor in the vessel. The feedstream is introduced to the vessel with a pressure drop to result in an initial flashing of the solvent from the solvent-containing droplets. Heat from the vessel atmosphere or from steam flowing countercurrent to the falling hydrocarbon droplets is transferred to the falling hydrocarbon droplets resulting in vaporization of any residual solvent therefrom. A substantially solvent-depleted pool is collected in the bottom of the vessel and retained only so long as is required to pump the underflow stream from the vessel.

Abstract: A continuous process for upgrading a heavy hydrocarbon includes the steps of: obtaining a heavy hydrocarbon; heating the heavy hydrocarbon; contacting the heavy hydrocarbon with a solvent at upgrading conditions so as to produce a first product comprising a mixture of upgraded hydrocarbon and solvent and a second product comprising asphaltene waste and water; continuously feeding the first product and the second product to a first separator; heating the first product; and continuously feeding the first product to a second separator to separate the upgraded hydrocarbon from the solvent. A system is also provided.

Abstract: An energy efficient, high throughput process for aromatics recovery can be readily implemented by revamping existing sulfolane solvent extraction facilities, or constructing new ones, so as to incorporate unique process operations involving liquid-liquid extraction and extractive distillation. Current industrial sulfolane solvent based liquid-liquid extraction processes employ a liquid-liquid extraction column, an extractive stripping column, a solvent recovery column, a raffinate wash column, and a solvent regenerator. The improved process for aromatic hydrocarbon recovery from a mixture of aromatic and non-aromatic hydrocarbons requires transformation of the extractive stripping column into a modified extractive distillation column. The revamping incorporates the unique advantages of liquid-liquid extraction and extractive distillation into one process to significantly reduce energy consumption and increase process throughput.

Abstract: Extractive distillation processes whereby water-soluble extractive distillation (ED) solvents are regenerated and recovered employ improved operations of the extractive distillation column (EDC) so that polar hydrocarbons are recovered and purified from mixtures containing polar and less polar hydrocarbons and measurable amounts of hydrocarbons that are heavier than intended feedstock and/or polymers that are generated in the ED process. The improved process can effectively remove and recover the heavy hydrocarbons and/or remove polymer contaminants from the solvent in a closed solvent circulating loop through mild operating conditions with no additional process energy being expended. With the improved process, the overhead reflux of the EDC may be eliminated to further reduce energy consumption and to enhance the loading and performance within the upper portion of the EDC, especially when two liquid phases exists therein.

Abstract: A process for upgrading a heavy hydrocarbon includes the steps of obtaining a heavy hydrocarbon; contacting the heavy hydrocarbon with a solvent at upgrading conditions so as to produce a first product comprising a mixture of upgraded hydrocarbon and solvent and a second product comprising asphaltene waste, water and solvent; and feeding the first product to a separator to separate the upgraded hydrocarbon from the solvent. A system is also provided.

Abstract: A tailings solvent recovery vessel substantially without conventional internals utilizes nozzles for forming very fine solvent-containing hydrocarbon droplets from a solvent-containing tailings feedstream. The hydrocarbon droplets are discrete from water droplets. The hydrocarbon droplets are small enough to result in a large surface area and a desired fall residence time but sufficiently large that they are not entrained with the rising vapour in the vessel. The feedstream is introduced to the vessel with a pressure drop to result in an initial flashing of the solvent from the solvent-containing droplets. Heat from the vessel atmosphere or from steam flowing countercurrent to the falling hydrocarbon droplets is transferred to the falling hydrocarbon droplets resulting in vaporization of any residual solvent therefrom. A substantially solvent-depleted pool is collected in the bottom of the vessel and retained only so long as is required to pump the underflow stream from the vessel.

Abstract: A process for recovering polar hydrocarbons from non-polar hydrocarbons, such as aromatics from non-aromatics, naphthenes from paraffins and isoparaffins, or olefins from paraffins and isoparaffins, in feed mixtures containing at least a measurable amount of heavier hydrocarbons. This improved extractive distillation (ED) process recovers aromatic hydrocarbons including benzene, toluene, and xylenes from the C6-C8 petroleum streams containing a measurable amount of C9+ hydrocarbons. The ED process also recovers benzene and toluene from the C6-C7 petroleum streams containing a measurable amount of C8+ hydrocarbons. The ED solvent utilized to recover and purify the aromatic hydrocarbons from the petroleum stream with a heavier than intended feedstock of hydrocarbons is also regenerated and recovered.

Abstract: A process for producing a purified aliphatic product from an aromatic-containing feedstock is disclosed.

Abstract: A solvent deasphalting of crude oil or petroleum heavy fractions and residues is carried out in the presence of a solid adsorbent, such as clay, silica, alumina and activated carbon, which adsorbs the contaminants and permits the solvent and oil fraction to be removed as a separate stream from which the solvent is recovered for recycling; the adsorbent with contaminants and the asphalt bottoms is mixed with aromatic and/or polar solvents to desorb the contaminants and washed as necessary, e.g., with benzene, toluene, xylenes and tetrahydrofuran, to clean adsorbant which is recovered and recycled; the solvent-asphalt mixture is sent to a fractionator for recovery and recycling of the aromatic or polar solvent. The bottoms from the fractionator include the concentrated PNA and contaminants and are further processes as appropriate.

Abstract: A process for the production of a pipeline-transportable crude oil from a bitumen feed, the process comprising: (1) dividing the bitumen feed into two fractions, the first fraction comprising between 20 and 80 wt % of the feed, the second fraction comprising between 80 and 20 wt % of the total feed, (the two fraction together forming 100 wt % of the feed), (2) distillation of the first fraction obtained in step (1) (preferably under vacuum) into a light fraction boiling below 380° C. (preferably the 450° C. fraction, more preferably the 510° C. fraction) and a residual fraction; (3) thermal cracking (of at least part of, preferably all of,) the residual fraction obtained in the distillation process described in step (2); (4) distillation of the product obtained in step (3) into one or more light fractions (boiling below 350° C.), optionally one or more intermediate fractions (boiling between 350 and 510° C.) and a heavy fraction (boiling above at least 350° C.

Abstract: Disclosed is a process for removing acids in a system in which aromatic hydrocarbons are separated from a mixture with aliphatic hydrocarbons. The aromatic hydrocarbons are extracted from the mixture using an extracting solvent. The aromatic hydrocarbons are stripped from the extracting solvent with steam and the steam is condensed to form water which is separated from the aromatic hydrocarbons. The separated water is passed through a basic anion exchange column and is then heated to produce the steam.

Abstract: This application relates to a composite solvent for separating aromatics by extractive distillation, comprising a main solvent, a solutizer and a modifier. Said solutizer is selected from any one or mixtures of any two of C8–C11 aromatics having different number of carbon atoms, the content of which is 3–39 wt %, and the number of carbon atoms of the lowest aromatic in the solutizer should be greater than that of the highest aromatic in the aromatics to be separated. When the solutizer is selected from any one of C8–C11 aromatics, the composite solvent contains 0.01–10.0 wt % of the modifier; when the solutizer is selected from mixtures of any two of C8–C11 aromatics having different number of carbon atoms, the composite solvent contains 0–10.0 wt % of the modifier. Said main solvent and modifier are independently selected from sulfolane derivatives, N-formyl morpholine, and N-methyl pyrrolidone, provided that the acidity and basicity of the modifier are opposite to those of the main solvent.

Abstract: A process for upgrading hydrocarbonaceous oil containing heteroatom-containing compounds where the hydrocarbonaceous oil is contacted with a solvent system that is a mixture of a major portion of a polar solvent having a dipole moment greater than about 1 debye and a minor portion of water to selectively separate the constituents of the carbonaceous oil into a heteroatom-depleted raffinate fraction and heteroatom-enriched extract fraction. The polar solvent and the water-in-solvent system are formulated at a ratio where the water is an antisolvent in an amount to inhibit solubility of heteroatom-containing compounds and the polar solvent in the raffinate, and to inhibit solubility of non-heteroatom-containing compounds in the extract. The ratio of the hydrocarbonaceous oil to the solvent system is such that a coefficient of separation is at least 50%.

Abstract: This invention is directed to a method of removing dimethyl ether from an olefin stream. Dimethyl ether is removed from the olefin stream by first separating the olefin stream into a first stream comprising dimethyl ether and lighter boiling point compounds, and a second stream comprising C4+ olefin and higher boiling point hydrocarbons. The dimethyl ether is then separated from the first stream using extractive distillation.

Abstract: A method for the continuous process of fluids is based on mixing the fluid with a supercritical fluid. The mixing of the two fluids may be accomplished using either a co-flow or counter-flow process. The process focuses on the difference in the solubilities of the desired and the undesired components into supercritical fluid and de-emphasizes the influence of the contaminating components of the fluid to be processed. The process of the present invention is particularly advantageous to the recycling of industrial waste fluids, such as used oil, wherein the process is carried out by jet spray micro-orifices atomization of waste material with a supercritical fluid to dissolve oil from the waste material. Additional mixing devices such as a magneto driven impeller shaft and ultrasonic gun may be employed. Thereafter, un-dissolved components are separated, first and the dissolved fluid is then separated from the supercritical fluid. Various apparatus for carrying out the method are also disclosed.

Abstract: The improved process and apparatus of the present invention for extracting high purity aromatics from gasoline using a glycol solvent based extraction process decrease liquid-vapor flashing, reduce reflux flow rate, and use heat of enthalpy produces at one point as a source of energy used at another point, decreasing energy consumption while significantly increasing purity and amount of product obtained.

Abstract: The present invention provides a process for the extraction of aromatics from petroleum fractions i.e. naphtha, kerosene and gas oil, using re-extraction route for recovery of solvent.

Abstract: An improved process for the recovery of aromatic compounds from a mixture containing aromatic and non-aromatic compounds and method for retrofitting existing equipment for the same is provided. The improved process comprises the steps of recovering aromatic compounds via parallel operation of a hybrid extractive distillation/liquid-liquid extractor operation and variations thereof. Methods of quickly and economically retrofitting existing recovery process equipment for use with the improved aromatics recovery process are also disclosed.

Abstract: A method of separating a petroleum-containing material into at least two fractions, an extraction system, and an extraction fluid therefor are provided. Petroleum-containing material as well as a solvent mixture comprising 50%-99% by volume sub-critical carbon dioxide and 1%-50% by volume of at least one co-solvent are introduced into an extraction column. The co-solvent can be propane, ethane, butane, propylene 2 methylpropane, 2,2 dimethylpropane, propadiene, dimethylether, chlorodifluoromethane, difluoromethane and methylfluoride. A fraction containing solvent mixture and solvated petroleum-containing material is removed from the top portion of the extraction column, while a dense fraction of the petroleum-containing material, as well as solvent mixture, is withdrawn from the bottom portion of the extraction column. Solvent mixture is recovered from the solvated petroleum-containing material.

Abstract: The improved process and apparatus of the present invention for extracting high purity aromatics from gasoline using a glycol solvent based extraction process decrease liquid-vapor flashing, reduce reflux flow rate, and use heat of enthalpy produces at one point as a source of energy used at another point, decreasing energy consumption while significantly increasing purity and amount of product obtained.

Abstract: A process for pre-treating a spent caustic stream prior to oxidation which includes countercurrent multi-stage elevated temperature solvent extraction of dissolved organic material from the spent caustic using a solvent to yield a spent caustic raffinate containing only residual amounts of organic solute and steam distilling the spent caustic raffinate to remove the residual organic solutes, yielding a pretreated spent caustic stream substantially free of organic material which is then subjected to wet air oxidation and thereafter to ozonolysis to yield a wastewater stream having a low COD and BOD, which is neutralized to a pH of 8.5 to 9.0.

Abstract: A method of generating power from residual fuel oil that is deasphalted with a flow of process steam to produce a deasphalted oil stream, a pitch stream, and a deasphalting condensate stream. The deasphalted oil stream is burned in a pressurized oxygen-bearing gas to produce a pressurized hot gas stream. This pressurized hot gas stream is expanded in a turbine that produces shaft power and an expanded gas stream. The expanded gas stream is cooled by transferring heat from it to a flow of feed water that becomes steam. A portion of the steam becomes at least part of the flow of process steam used to deasphalt the residual fuel oil, thus integrating the deasphalting and the steam generation.

Abstract: A process for pretreating a spent caustic stream prior to oxidation includes countercurrent multi-stage elevated temperature solvent extraction of dissolved organic material from the spent caustic using a solvent to yield a spent caustic raffinate containing only residual amounts of organic solute. The raffinate is steam distilled to remove the residual organic solutes, yielding a pretreated spent caustic stream substantially free of organic material. The pretreated spent caustic is suitable for use in a Kraft paper process or for oxidation prior to recycle or disposal. Solvent extract from the extractor is regenerated in a solvent regenerator having an overhead stream for purging light ends, a bottom stream for purging heavy ends, and a heart-cut side stream for recycling solvent to the extractor.

Abstract: Disclosed is a process for reducing corrosion in a system in which aromatic hydrocarbons are separated from a mixture with aliphatic hydrocarbons. The aromatic hydrocarbons are extracted from the mixture using an extracting solvent. The aromatic hydrocarbons are stripped from the extracting solvent with steam and the steam is condensed to form water which is separated from the aromatic hydrocarbons. The separated water is passed through a basic anion exchange column and is then heated to produce the steam.

Abstract: Solvent deasphalting apparatus includes a separator that receives two inputs, a heavy hydrocarbon feed and a solvent feed; and the apparatus produces two outputs, an asphaltene/solvent stream and a deasphalted oil/solvent stream. A solvent recovery unit of the apparatus receives the two output streams and produces mainly a substantially solvent-free deasphalted oil product stream, a substantially solvent-free asphaltene product stream, and a recovered solvent stream which is returned to a solvent drum. A pump pumps a substantially constant volume of solvent from the solvent drum into a by-pass line connecting the pump to the solvent drum, and into a connection line connecting the pump to the separator. The amount of solvent flow in the connection line is functionally related to the level of heavy hydrocarbon feed so that solvent in excess of that flowing into the connection line and spills back to the solvent drum through the by-pass line.

Abstract: Power is generated in an organic Rankine cycle turbine by expanding a stream of solvent vapor produced by a flash drum in a deasphalting unit to produce a stream of expanded solvent vapor that is combined with a stream of solvent vapor and steam from a stripper of the deasphalting unit. Heat is extracted from the combined stream by an organic fluid that is vaporized and supplied to a Rankine cycle organic vapor turbine that produces power and expanded organic vapor. The solvent is recovered from the cooled, combined stream and re-used in the deasphalting unit. Heat extracted from products of the deasphalting unit vaporizes an organic fluid that is expanded in an organic vapor turbine that generates power.

Abstract: A method and apparatus for changing the solvent composition in a solvent recovery system of a dewaxing apparatus, depending on the type of stock oil, by introducing a part of dry solvent into a wet solvent tank to thereby increase or decrease a concentration of MEK in the wet solvent used as a primary solvent for initially mixing with the stock oil.

Abstract: A process for obtaining a fuel for internal combustion engines from a hydrocarbon charge, comprising a step (a) for distillation (D1) in which a bottom product (Q1) is obtained via a line 3 and in which a top product (T1) is obtained via a line 2, a step (b) of liquid/liquid extraction (LE) using a solvent (S1) to obtain a raffinate to (R1), (line 5) and an extract from which product (Q1) an extract (E1) is obtained (line 6) and a raffinate, a step c) of separating (D2) the raffinate (R1) enabling a product (Q2) to be obtained via line 7, which product has a low solvent (S1) content, and a step (d) of hydrotreatment (HDS) in which the mixture of the products (T1) and (Q2) are subjected to hydrotreatment with a hydrogen partial pressure of less than 10 megapascals, to obtain a product (P) (line 9) which has improved qualities and which contains less than 500 ppm by weight sulphur.

Abstract: A method of dehydrating a solvent originating from a hydrocarbon dewaxing operation, wherein a moist composite organic solvent, for example a moist MEK/toluene mixture is dehydrated in a first distillation zone, the resulting first distillate is contacted with water to form two phases one of which, rich in organic solvent, is returned as a reflux to the first distillation zone whereas the other phase rich in water is distilled in a second distillation zone, and the head product and one portion of the bottom product of the second distillation zone are returned to the zone of contact between the first distillate and water, the invention being applicable to the dewaxing of lubricating oils.

Abstract: Thermal degradation of furfural in solvent refining of lubricating oil stocks is reduced by use of a thin-film evaporator for the final stages of furfural recovery, permitting increased pressure to be used in each stage of furfural recovery.

Abstract: Processes are disclosed for the separation of aromatic hydrocarbons from feedstreams containing mixtures of aromatic and non-aromatic hydrocarbons using extractive distillation with an aromatic selective solvent in order to separate the aromatic hydrocarbons from the non-aromatic hydrocarbons. A rich solvent stream comprising the aromatic hydrocarbons and solvent is withdrawn from the extractive distillation column and passed to a steam stripping column to provide a regenerated lean solvent stream, a side-cut stream comprising the aromatic hydrocarbons and a stripper overhead stream comprising non-aromatic hydrocarbons which are passed as a reflux stream to the extractive distillation column. Various solvents are disclosed and an especially preferred solvent is sulfolane.

Abstract: A method is provided for the recovery of aromatic hydrocarbons from the extract phase of aromatic-selective solvent extraction process which involves withdrawing a vapor side-cut fraction containing aromatic hydrocarbons and solvent from a stripping zone and passing the side-cut fraction to a rectification zone which can be refluxed with an aqueous condensate. The benefits of the invention are that the introduction of the rectification zone bottoms to the bottom of the stripping section provides an aromatic product comprising less than 100 wt. ppm. solvent, provides improved stripping over prior schemes, and reduces the flowrate of stripping medium throughout the stripping zone which results in energy saving.