Abstract: Oxo-nitrogenated iron complex having general formula (I): in which: R1 and R2, identical or different, represent a hydrogen atom; or they are selected from linear or branched, optionally halogenated C1-C20, preferably C1-C15, alkyl groups, optionally substituted cycloalkyl groups, optionally substituted aryl groups; R3 represents a hydrogen atom, or it is selected from linear or branched, optionally halogenated C1-C20, preferably C1-C15 alkyl groups, optionally substituted cycloalkyl groups, optionally substituted aryl groups; X, identical or different, represent a halogen atom such as, for example, chlorine, bromine, iodine, preferably chlorine; or they are selected from. linear or branched C1-C20, preferably C1-C15, alkyl groups, —OCOR4 groups or —OR4 groups in which R4 is selected from linear or branched C1-C20, preferably C1-C15, alkyl groups; n is 2 or 3.

Abstract: Apparatus for treating liquids, includes •a vapour inlet (201); •a vessel (202) for housing liquid, the vessel being in fluid communication with the vapour inlet; and, •a vapour outlet (204); configured such that in use •vapour from the vapour inlet passes into liquid housed in the vessel; and •liquid from the vessel can interact with material housed in a chamber (203) in fluid communication with the vessel; •vapour from the liquid can pass to the vapour outlet. The apparatus can be used in distilling spirits in particular gin or rum.

Abstract: Recovering high purity benzene from hydrocarbon feedstock containing aromatics and non-aromatics is implemented by simple and low-cost modifications to conventional extractive distillation columns (EDCs). Methyl cyclohexane (MCH) that is generated through non-selective hydrogenation of toluene in hydrodesulfurization (HDS) units is a major contaminant in benzene production. To meet MCH specifications, often times the extractive distillation (ED) process for recovering purified benzene is operated with excessive benzene loss to the overhead raffinate stream, producing a lower quality non-aromatic product.

Abstract: Processes for the reduction and/or removal of permanganate reducing compounds (PRC'S) formed by the carbonylation of methanol in the presence of a Group VIII metal carbonylation catalyst to produce acetic acid are disclosed. More specifically, processes for reducing and/or removing PRC's or their precursors from intermediate streams during the formation of acetic acid by said carbonylation processes are disclosed. In particular, processes in which a low boiling overhead vapor stream from a light ends column is subjected to a distillation to obtain an overhead that is subjected to an extraction to selectively remove and/or reduce PRC's from the process is disclosed. The processes include steps of recycling one or more return streams derived from the distillation step and/or the extraction step to a light ends column and/or a drying column in order to improve water control in the overall reaction system.

Abstract: An onsite purification plant/system to delivery high and ultra high purity product, such as, process chemicals, industrial and specialty gases to manufacturing processes within the onsite plant turndown ratio from 0% to 100% while preserving the predetermined purity of the supplied substances within a predefined specification range is provided. Preserving liquid/vapor ratio in at least one of the purification means/units ensuring that product purity range stays unchanged is achieved by redirecting the product back into the onsite purification plant/system.

Abstract: The present invention relates to processes for producing and recovering ethanol using an intermediate reboiler. An intermediate stream may be withdrawn from a removal zone of a distillation column and recirculated through the intermediate reboiler to the distillation column. The distillation column may also comprise a bottoms reboiler.

Abstract: An aromatics complex producing one or more xylene isomers offers a large number of opportunities to conserve energy by heat exchange within the complex. One previously unrecognized opportunity is through providing two parallel distillation columns operating at different pressures to separate C8 aromatics from C9+ aromatics. The parallel columns offer additional opportunities to conserve energy within the complex through heat exchange in associated xylene recovery facilities.

Abstract: A method for producing an olefin oligomer mixture comprising: feeding a raw olefin oligomer mixture to a first evaporator; feeding a residue which is taken out from the first evaporator to a second evaporator, and returning a distillate which is distilled from the second evaporator to the first evaporator; taking a distillate out from the first evaporator; feeding a residue which is taken out from the second evaporator to a third evaporator; and taking a distillate out from the third evaporator.

Abstract: Disclosed is a process for improving the efficiency of a combined-cycle power generation plant and desalination unit. The process includes supplying exhaust gases from a gas turbine set used to generate electrical power to a heat recovery steam generator (HRSG) and then directing the steam from the HRSG to a steam turbine set. Salinous water is supplied into an effect of the desalination unit. Steam exhausted from the steam turbine set is utilized in the effect of the desalination unit to produce a distillate vapor and brine from the effect by heat exchange. Additionally, steam is introduced steam from at least one additional heat source from the combined-cycle power generation plant to the effect to increase the mass flow rate of steam into the effect. In one embodiment, the additional heat source is an intercooler heat exchanger. Heated water from the intercooler heat exchanger is provided to a reduced atmosphere flash tank, and the steam flashed in the flash tank is provided to the effect.

Abstract: A method of dehydrating tolylenediamine which includes subjecting tolylenediamine having a water content of 5-40 wt. % to first-stage distillation at a vacuum of 13-101.3 kPa and subjecting the bottoms from the first-stage distillation to second-stage distillation at a vacuum lower than 13kPa.

Abstract: Disclosed herein are processes for separation of 2,3,3,3-tetrafluoropropene and hydrogen fluoride using azeotropic distillation. Additionally, disclosed are processes for separating mixtures of 2,3,3,3-tetrafluoropropene, hydrogen fluoride and 1,1,1,2,3-pentafluoropropane (HFC-245eb) and/or 1,1,1,2,2-pentafluoropropane (HFC-245cb) by azeotropic distillation.

Abstract: Embodiments of the present disclosure provide processes, columns, and systems for removing acetaldehyde from alkylene oxide in a feed stream and for providing an alkylene oxide-water stream that can be directly transferred to a glycol reaction process. The alkylene oxide purification column includes a first section to convert a feed stream into a gas phase portion and a liquid phase portion and a second section located in the column above the first section to separate alkylene oxide from the acetaldehyde, water, and other impurities that enter the second section from the first section.

Abstract: Crude fluoroethylene carbonate obtained by the fluorination of ethylene carbonate and elemental fluorine containing not more than 5% by weight of HF is purified by at least two subsequent distillation steps. The bulk of HF can be removed, if desired, in a preliminary HF removal step, e.g., by stripping, before performing the distillation. Further, if desired, a second HF removal step can be performed by contacting the crude mixture or the distillate obtained after the first distillation step with an adsorbent for HF, e.g., silica gel. The distillation can be performed batch wise. It is preferred to perform the distillation continuously. It yields purified fluoroethylene carbonate with an HF content of equal to or less than 30 ppm. The purified fluoroethylene carbonate can be applied as solvent additive for lithium ion batteries.

Abstract: The invention is a method for processing a mixture containing water, 3-methyl-1-butene and at least one other methylbutene. The method comprises primary distillation of the mixture, giving a gaseous primary overhead product containing methylbutene and water and a water-free primary bottom product containing 3-methyl-1-butene; condensation of the gaseous primary overhead product so as to give a condensate comprising a liquid aqueous phase and a liquid organic phase; separation of the condensate into a liquid aqueous phase and a liquid organic phase; discharge of the liquid aqueous phase; recirculation of the organic phase to the primary distillation; and finally secondary distillation of the water-free primary bottom product from the primary distillation so as to give a secondary overhead product comprising 3-methyl-1-butene and a secondary bottom product. The secondary overhead product obtained has a purity which enables it to be used directly as monomer or comonomer for preparing polymers or copolymers.

Abstract: Processes and systems for purifying silane-containing streams are disclosed with relatively less silane being lost in impurity streams by use of distillation and/or condensation operations.

Abstract: An azeotropic distillation method, comprising a reaction step, a distillation step for separating and refining a reaction product, and a recovery step for collecting a reactant after the distillation step; wherein at least one component constituting the reactant in the reaction step can act as an entrainer for the azeotropic distillation in the distillation step; and a portion of the reactant capable of acting as the entrainer is supplied to the distillation step.

Abstract: An apparatus and process for the separation of refrigerant mixtures is provided. The apparatus includes a first distillation column, a first condenser, and a first collection vessel. The apparatus also includes a sorter vessel that includes a sorter agent, wherein the sorter vessel is fluidly connected to the first distillation column.

Abstract: A method for recovering base oil from waste lubricating oil by separating base oil range constituents from a waste lubricating oil mixture, thereafter separating higher quality base oil constituents and lower quality base oil constituents from the base oil recovered from the waste lubricating oil mixture and thereafter treating the lower quality base oil constituents to produce marketable base oil. The total base oil produced from a waste lubricating oil mixture by this process is greater than the quantity producible by previous processes using only base oil separation from the waste lubricating oil mixture or processes which use only treatment of the base oil recovered from the waste lubricating oil mixture to produce the product base oil.

Abstract: A method for the separation of hydrocarbon compounds utilizing a dividing wall distillation column is described. The dividing wall distillation column enables one or more side draw stream to be removed from the dividing wall distillation column in addition to an overhead stream and a bottoms stream.

Abstract: The present disclosure relates, according to some embodiments, to apparatus, systems, and/or methods for fractionating a feed mixture comprising, for example, one or more isocyanates, light components, solvents and/or heavier components. In some embodiments, fractionating an isocyanate feed mixture may comprise distilling the feed mixture in a non-adiabatic fractionating apparatus comprising a prefractionating section and/or column and a main section and/or column, which comprises a rectification section, a side section, and a stripping section. For example, isocyanates may be separated from light component(s), solvent(s) and/or heavier component(s). A fractionating apparatus may be configured and arranged, in some embodiments, as a dividing wall column. According to some embodiments of the disclosure, apparatus, systems, and/or methods may be energy efficient and/or may have a broad operating range.

Abstract: The present invention relates to a system for producing ethanol from an organic source and that operates to purify and dry ethanol from a beer source. The system for producing substantially anhydrous ethanol comprises: (a) a first distillation stripping column; (b) a second distillation rectifying column having a higher operating temperature than said stripping column; (c) a molecular sieve dehydration means in fluid communication with said rectifying column. Heat from the overhead of the second distillation rectifying column and the molecular sieve dehydration are used to heat the first distillation stripping column.

Abstract: A distillation system for distilling influent liquid includes a counterflow heat exchanger for receiving and heating the influent liquid. A heater is coupled to the counterflow heat exchanger for receiving the influent liquid from the counterflow heat exchanger and heating the influent liquid. An evaporation unit is coupled to the heater and to a sump for receiving the influent liquid from the heater and for receiving liquid from the sump and forming a vapor from at least a portion of the influent liquid and the liquid received from the sump. The evaporation unit returns unevaporated liquid to the sump. A condensation unit is coupled to the evaporation unit for forming a condensate from vapor received from the evaporation unit. The condensation unit is coupled to the counterflow heat exchanger for transferring the condensate to the counterflow heat exchanger. The heater simultaneously heats the liquid in the sump and the influent liquid received from the counterflow heat exchanger.

Abstract: The present invention relates to a process for the separation by distillation of a hydrocarbon-containing feed stream comprising olefin monomer, co-monomer and hydrocarbon diluent. The present invention also relates to a distillation system comprising a distillation column for carrying out the process according to the invention.

Abstract: The present invention relates to a process for the purification of an aqueous stream coming from the Fischer-Tropsch reaction which comprises:—feeding of the aqueous stream containing the organic by-products of the reaction to a system consisting of a distillation column equipped with a partial condenser and a total condenser;—partial condensation of the vaporized stream leaving the head of the column and collection of a first distillate enriched in the heavier by-products;—total condensation of the vaporized stream leaving the partial condenser and collection of a liquid stream which is partly sent back to the distillation column as reflux whereas the remaining part is collected as distillate;—extraction of the purified aqueous stream from the bottom of the distillation column.

Abstract: The present invention provides a process for distillatively purifying crude aqueous 1,4-butanediol (1), in which 1,4-butanediol (5) freed of components having lower boiling points than 1,4-butanediol and water is passed through three distillation columns (III, IV, V), components having a higher boiling point than 1,4-butanediol are drawn off from the bottom of the first column and conducted into the third (7), 1,4-butanediol from the top of the first column (6) is conducted into the second, the bottom product of the second column (9) is conducted into the third, the top product of the third column (11) is recycled at least partly into the first column, wherein the very pure 1,4-butanediol is withdrawn from a side draw of the second column.

Abstract: Novel distillation processes for reducing the heat duty requirement of petroleum crude distillation as compared to the conventional distillation process are described. These processes are also applicable for distillation of other multi-component mixtures similar to petroleum crude.

Abstract: This ethylbenzene process involves contacting, in an alkylation zone, a first benzene recycle stream and an ethylene feed stream with an alkylation catalyst to form ethylbenzene. In a transalkylation zone, a polyethylbenzene recycle stream and a second benzene recycle stream are contacted with a transalkylation catalyst to form additional ethylbenzene. The effluents are passed into a dividing wall distillation column. An ethylbenzene stream is removed from an intermediate point of the dividing wall fractionation column; a first benzene recycle stream is removed from a first end and a flux oil stream is removed from a second end. A second benzene recycle stream is removed from an intermediate point located between the first end and the ethylbenzene stream. A polyethylbenzene stream is removed from an intermediate point of located between the second end and the ethylbenzene stream.

Abstract: This cumene process involves contacting, in an alkylation zone, a first benzene recycle stream and a propylene feed stream with an alkylation catalyst to form cumene. In a transalkylation zone, a polyisopropylbenzene recycle stream and a second benzene recycle stream are contacted with a transalkylation catalyst to form additional cumene. The effluents are passed into a benzene distillation column. From the benzene distillation column, a first benzene recycle stream is removed as overhead; a second benzene recycle stream is removed as a side draw; and a bottoms stream comprising polyisopropylbenzene, cumene, and heavy aromatics is removed from an end. The bottoms stream is passed to a dividing wall distillation column where the polyisopropylbenzene recycle stream is removed from an intermediate point; a cumene product stream is removed from a first end, and a heavy aromatic stream is removed from a second end.

Abstract: This cumene process involves contacting, in an alkylation zone, a first benzene recycle stream and a propylene feed stream with an alkylation catalyst to form cumene. In a transalkylation zone, a polyisopropyl benzene recycle stream and a second benzene recycle stream are contacted with a transalkylation catalyst to form additional cumene. The effluents are passed into a dividing wall distillation column. A cumene stream is removed from an intermediate point of the dividing wall fractionation column; a first benzene recycle stream is removed from a first end and a heavy aromatics stream is removed from a second end. A second benzene recycle stream is removed from an intermediate point located between the first end and the cumene stream. A polyisopropyl benzene stream is removed from an intermediate point of located between the second end and the cumene stream.

Abstract: This ethylbenzene process involves contacting, in an alkylation zone, a first benzene recycle stream and an ethylene feed stream with an alkylation catalyst to form ethylbenzene. In a transalkylation zone, a polyethylbenzene recycle stream and a second benzene recycle stream are contacted with a transalkylation catalyst to form additional ethylbenzene. The effluents are passed into a dividing wall distillation column where a benzene overhead and a benzene side draw are removed and recycled. An ethylbenzene stream product stream is also removed. The remainder, largely polyethylbenzene and tar, is passed to a polyethylbenzene column for separation. The separated polyethylbenzene is recycled to the transalkylation reactor.

Abstract: In an alkylation zone, a benzene recycle stream and a propylene feed stream are contacted with an alkylation catalyst to convert the propylene and benzene into cumene. In a transalkylation zone, a polyisopropylbenzene stream and a benzene recycle stream are contacted with a transalkylation catalyst to convert the polyisopropylbenzene and benzene into cumene. The alkylation and transalkylation zone effluents are passed into a dividing wall fractionation column. A cumene product stream is removed from an intermediate point of the dividing wall fractionation column. A benzene recycle stream is removed from a first end, and another benzene recycle stream is removed from an intermediate point of the dividing wall fractionation column. A polyisopropylbenzene stream is removed from a second end of the dividing wall fractionation column. The polyisopropylbenzene stream is passed to a polyisopropylbenzene fractionation column to separate the polyisopropylbenzene from a heavy ends stream.

Abstract: Improved processes and apparatus use a finishing column with a mid-cut that provides alkylbenzene products of high purity containing less than about 1 ppmw benzene and less than about 50 ppmw heavies while accommodating enhancements in the efficiencies and the capacities of the distillation train to recover alkylbenzene from alkylation reaction product and while enabling the use of catalytic treatments to reduce olefinic-component content.

Abstract: This invention is an improved distillation sequence for the separation and purification of ethylene from a cracked gas. A hydrocarbon feed enters a C2 distributor column. The top of the C2 distributor column is thermally coupled to an ethylene distributor column, and the bottoms liquid of a C2 distributor column feeds a deethanizer column. The C2 distributor column utilizes a conventional reboiler. The top of the ethylene distributor is thermally coupled with a demethanizer column, and the bottoms liquid of the ethylene distributor feeds a C2 splitter column. The ethylene distributor column utilizes a conventional reboiler. The deethanizer and C2 splitter columns are also thermally coupled and operated at a substantially lower pressure than the C2 distributor column, the ethylene distributor column, and the demethanizer column. Alternatively, a hydrocarbon feed enters a deethanizer column.

Abstract: A mixture comprising at least 1,1,1,3,3-pentafluoropropane and 1,1,1-trifluoro-3-chloro-2-propene is subjected to a distillation operation, and thereby, a distillate comprising an azeotropic composition consisting substantially of 1,1,1,3,3-pentafluoropropane and 1,1,1-trifluoro-3-chloro-2-propene is obtained and a bottom product comprising 1,1,1,3,3-pentafluoropropane or 1,1,1-trifluoro-3-chloro-2-propene which each is separated and purified.

Abstract: A process produces ?-caprolactone by the oxidation of cyclohexanone by feeding a crude reaction mixture to a first distillation column; distilling off a first distillate containing low boiling components including unreacted cyclohexanone from the top of the first distillation column; recovering a first side-cut fraction containing unreacted cyclohexanone in a higher concentration than in the first distillate from an intermediate tray; recovering a first bottom liquid containing high boiling components including ?-caprolactone from the bottom; introducing the first side-cut fraction to a second distillation column; recovering a second bottom liquid containing unreacted cyclohexanone from the bottom of the second distillation column; recycling the second bottom liquid into the raw material cyclohexanone; introducing the first bottom liquid to a third distillation column to thereby yield a third distillate containing ?-caprolactone from the third distillation column.

Abstract: For the purification of the norbornene obtained by the reaction of dicyclopentadiene or cyclopentadiene and ethylene, the crude reaction mixture containing light impurities having boiling temperatures lower than that of norbornene; medium-heavy impurities having the boiling temperatures between that of norbornene and that of ethylnorbornene; and heavy impurities containing ethylnorbornene and compounds boiling higher than ethylnorbornene, boiling temperatures greater than that ethylnorbornene, a first distillation of the crude reaction mixture is carried out in a tailing column (C1), removing a portion of the heavy impurities and a portion of the medium-heavy impurities; then a second distillation of the crude mixture, thus tailed, is carried out in a topping column (C2), removing the light impurities; and a third distillation of the mixture, thus topped, is subsequently carried out in a tailing column (C3), removing the remainder of the heavy and medium-heavy impurities.

Abstract: Acetals are produced from the reaction of aldehydes and alcohols, e.g. methylal by the reaction of methanol and formaldehyde, by the reaction in a reaction distillation column of the alcohol and aldehyde in the presence of a catalyst and the concurrent fractional distillation of the reaction mixture to separate the reaction products, water and acetal.

Abstract: The invention concerns a process for the separation of a mixture comprising ethylene, 1-butene, alpha-olefins containing at least 6 carbon atoms per molecule and possibly heavier hydrocarbon products, the ethylene content of the mixture being in the range 30% to 70% by weight, in which separation is effected in a distillation zone to obtain an overhead fraction comprising the major portion of the ethylene present in the mixture and between 0% and 100% by weight of the 1-butene present in the mixture, the process being characterized in that the zone is also supplied with supplemental 1-butene in an amount in the range 1 to 40 times the quantity (by weight) of 1-butene present in the mixture. In a preferred implementation of the process of the invention, the mixture originates form a homogenous liquid phase ethylene oligomerisation zone.

Abstract: There is provided a purification process for dimethoxymethylsilane in which a mixture containing dimethoxymethylsilane and methanol is subjected to a first distillation step in which the mixture is distilled in the presence of methyl formate or methoxytrimethylsilane so that a distillate fraction containing methanol and methyl formate or methoxytrimethylsilane is distilled off and a balance fraction containing dimethoxymethylsilane and methanol is discharged, the amount of methanol in the balance fraction being substantially reduced relative to that of the mixture.

Abstract: A process for the purification of raw acetone deriving from processes for the production of phenol acetone, impurity mainly due to cumene, water, aldehydes and methanol, the steps of:feeding the stream of raw acetone coming from the primary fractionation of a plant for the production of phenol and acetone to a first distillation column to which a solution of sodium hydroxide at 2% is also fed;sending the stream at the head of the first column, containing of acetone, water and cumene to a second column to which the extractive solvent triethyleneglycol is also fed;recovering substantially anhydrous acetone from the head of the second column;feeding the bottom product of the second column, containing triethyleneglycol, water, cumene and acetone to a third distillation column in which an azeotropic mixture of water and cumene is recovered from the head and anhydrous triethyleneglycol from the bottom;sending the azeotropic mixture of water and cumene to a decanter in which a water phase is separated, containing ac

Abstract: The production of high purity benzene and high purity toluene is obtained by utilizing the initial gas separating column for the treatment of the aromatic containing starting material as a separating column for separating a benzene rich from a toluene rich component. The benzene rich component is subject directly to distillation while the toluene is subject to predistillation to separate high boiling components and only then to extractive distillation is distilled to separate the high purity benzene from the high purity toluene.

Abstract: The invention is a process for reducing capital and energy costs in ethylene recovery. Moderate pressure processing and thermally coupled fractionation steps are achieved through the use of integrator columns. Ethylene separation from cracked gas originating from ethane through gas oil feeds can now be done with thermodynamically efficient fractionation at capital cost competitive with low efficiency designs. Acetylene hydrogenation may be done before demethanization where desired, and dephlegmation is preferred to accomplish high-efficiency rectification of hydrogen and methane from ethylene. Open loop heat pumps can optionally be incorporated into the ethane/ethylene splitter fractionation step, whose desirability is controlled by optimization of capital and energy costs.

Abstract: The invention relates to a process for the treatment of contaminated ethylene glycol resulting during a polycondensation process for the production of polyester. In the course of this polycondensation process contaminated ethylene glycol is continuously predistilled, subjected as a distillation residue to secondary distillation, condensed and then returned to the polycondensation process as decontaminated ethylene glycol, so that an in-line recovery is achieved, which makes superfluous an external distillation installation for the treatment of contaminated ethylene glycol.

Abstract: An apparatus and method for treating chemical production plant process condensate such that a contaminant-rich stream and a relatively pure aqueous stream is separately recoverable from the condensate, wherein the contaminants are substantially removed from the condensate by steam stripping and subsequent rectification in a relatively low pressure stripping/rectification tower. The tower overhead is then condensed with a portion of the condensed overhead being returned to the top of the rectification section of the tower as reflux and the balance being withdrawn as a concentrated stream for reuse in the plant. In a second embodiment, separate stripping and rectification towers operate in series whereby the overhead of the stripping tower is delivered to the lower section of the rectification tower and the rectification bottoms are returned to the top of the stripping tower.

Abstract: Crude propylene oxide is purified by a distillation process wherein it is (a) extractively distilled in a first column using a C.sub.2 to C.sub.6 alkylene glycol extractive distillation agent to form a first overhead fraction comprising propylene oxide, C.sub.5 -C.sub.7 hydrocarbons, methanol, water and oxygen-containing impurities, (b) wherein the first overhead fraction is separated in a plurality of intermediate distillation columns to provide an intermediate propylene oxide overhead fraction consisting essentially of propylene oxide and water, and (c) the intermediate propylene oxide overhead fraction is charged to a final distillation column using a C.sub.2 to C.sub.6 alkylene glycol extractive distillation agent to form a final overhead fraction consisting essentially of propylene oxide.

Abstract: The invention generally relates to a process for the purification of a component of a binary azeotrope in which the composition of the azeotrope changes by about 10 mole percent with pressure comprising:(a) subjecting a binary azeotrope to a distillation step in which most of one of the binary components is removed as distillate (distillate 1) with the bottoms (bottoms 1) enriched in the other component;(b) subjecting distillate 1 to at least one additional distillation step conducted at a different pressure in which most of the component recovered as bottoms 1 is removed as distillate 2 with the bottoms 2 enriched in the component enriched in distillate 1;(c) optionally repeating step (b) as many times as desired; and(d) recovering the desired purified component.The invention is particularly useful in the purification of pentafluoroethane in a pentafluoroethane/chloropentafluoroethane azeotrope.

Abstract: Where side stream distillate strippers are used in the distillation of hydrocarbons, the required size of the distillation column and the amount of stripping gas or vapor required are reduced by passing components stripped from the distillates through a plurality of strippers in series, rather than directly back to the distillation zone.

Abstract: A product stream containing, inter alia, HCl, HF and fluorocarbons which form close boiling point azeotropes with HF is subjected to distillation using sidestream rectification in order to effect energy efficient separation of selected fluorocarbon/HF azeotropes from one another.

Abstract: A method of distillation employing a heat pump (which may be driven by a compressor) using a vapor stream from within the distillation system as a heat source and a liquid stream from within the distillation system as a heat sink. The selection of heat-source vapors and heat-sink liquid is such that at least one is withdrawn from the phase-contracting region of the distillation system. The return of streams withdrawn from the phase-contacting region of the distillation system to the distillation system is such that at least one of the streams is returned at a temperature different from that of the point from which it was withdrawn, and all withdrawn streams are returned in manner such that a stream removed as vapor is returned at a point with a temperature at most that at the point it was withdrawn, and a stream removed as liquid is returned at a point with a temperature at least that at which it was withdrawn.

Abstract: A process for obtaining a substantially dry alcohol from a mixture comprising alcohol and water in a non-azeotropic amount by utilizing at least a portion of the alcohol in the mixture as the stripping medium.