Abstract: This invention relates to a method of regenerating an alcohol-based antifreezing liquid, and more particularly to a method of concentrating and regenerating an alcohol-based antifreezing liquid diluted through water absorption by removing water therefrom.The antifreezing liquid containing water is introduced into an evaporation vessel. The liquid is then heated to a temperature at which components other than alcohol of the liquid are unlikely to be affected in their properties while air is fed thereinto. Thus alcohol and water vapors are generated. These vapors are first cooled to a temperature at which only water is condensed. After water is removed, cooling is effected at a lower temperature. At this stage, the alcohol vapor is condensed, and thus concentrated alcohol, almost water-free, is collected.The alcohol thus collected and nonfreezing and high boiling-point components other than alcohol in the evaporation vessel are again mixed into a concentrated antifreezing liquid.

Abstract: A process for purifying impure water, e.g. heavy water, which provides for the removal of dissolved inorganic and organic contaminants by distillation of the water and washed vapor withdrawal, and optional chemical pretreatment of oxidazable matter.

Abstract: The present invention relates to a dry cleaning apparatus in which a main portion of a dry cleaner comprises tanks for exclusively receiving at least two kinds of solvents which are soluble in each other, one treating tank and a fractionating device for recovering the two or more kinds of solvents by batch distillation, exclusive filters for the respective solvents comprising, a common filter or a multi-filter device composed of both the filters, and the two or more kinds of solvents are used independently so that washing is carried out.

Abstract: The invention concerns a process for the degassing, dehydrating and lower boiling component separation during straight-run distillation of crude fatty acids. The crude fatty acids are degassed in the degassing stage at such temperatures and pressures in counter current flow with stripping steam that no appreciable dehydration or lower boiling component separation takes place at this stage, then the degassed crude fatty acid is then led to a precut column for dehydration and lower boiling component separation, whereby the falling film concentrator column operates as a partial condensation stage for the creation of the reflux of the fatty acids, which is necessary for the lower boiling component separation, and that the easily boiling component evaporates almost completely in the precut column and is led off from the precut column in vapor form, together with the water.

Abstract: A process for the condensation of a volatile-rich vapor stream produced by a stripping operation from a vegetable or fruit product or the extract thereof, which comprises the steps of:(i) condensing a major proportion of the water present in the vapor stream using a surface condenser with water as a coolant;(ii) subjecting the condensate of step (i) to further cooling in a heat-exchanger using water at a lower temperature than that of step (i) as the coolant; and(iii) contacting the cooled condensate from step (ii) with the vapor stream issuing from the condenser of step (i) in a countercurrent absorption column.The process is particularly applicable to the condensation of a volatile-rich water vapor stream containing coffee volatiles.

Abstract: Apparatus for concentrating and dehydrating maleic acid to form maleic anhydride, comprising: at least a first and a second vertical, independent and distinct, falling thin-film, multitubular evaporators of the static type arranged in series, wherein the first thin-film multitubular evaporator of the static type has an upper part and a lower part and includes a feedpipe at the upper part and a discharge pipe at the lower part; a separator connected by its sidewall to the discharge pipe from the first evaporator and including a first discharge pipe at the upper portion thereof and a second discharge pipe at the lower part; the second thin-film multitubular evaporator of the static type having a feedpipe having an upper part and a lower part connected to the second discharge pipe from the separator and including a discharge pipe only at the lower part thereof; a boiler having an upper part and a lower part, said upper part of said boiler being connected to and in open communication with the lower portion of the

Abstract: An improved process for purification of glycerol obtained from natural sources comprising alkalizing a glycerol-containing crude mixture in the presence of air for oxidation, evaporating the mixture in a thin-layer evaporator with redistillation of the residue, rectification and reevaporation in a packed column characterized by low-pressure-loss plates with a falling-film evaporator designed for internal and external partial condensation and to separate off unwanted constituents of the mixture, bleaching the product with activated carbon and separating the bleach in known manner.

Abstract: A process for the multi-stage condensation of an overhead fraction is disclosed. The process facilitates optimal response to changes in distillation column controls wherein column top reflux condensation is preferentially returned to said distillation column, but auxiliary surge capacity is obtained by connection to a first accumulator section of an accumulating zone, which surge capacity is supplemented by one-way flow of liquid from a cooler, second section in said accumulation zone.

Abstract: In a hydroformylation process wherein an alpha-alkene of 2 to about 10 carbon atoms is reacted with carbon monoxide and hydrogen in the presence of a rhodium triorganophosphine complex to produce an aldehyde having one carbon atom more than the alkene, the aldehyde product being continuously separated from the liquid reaction medium by gas stripping or distillation, rhodium moiety is recovered from the condensed reactor overhead vapors by redistillation under defined conditions.

Abstract: A method of processing fermented liquid comprising(a) feeding said fermented liquid into a vacuum vaporizer, (b) heating the feed in said vaporizer to separate it into a vapor and a concentrated liquid fraction, (c) recycling said vapor to said vaporizer by compression so as to achieve heat-exchange with said feed therein thereby generating a new vapor and a condensate fraction; said condensate being discharged as a distillate, (d) supplying the remaining compressed vapor to a multistage distilling column, (e) separating said compressed vapor into two fractions, one with a higher boiling point than the other, within said distilling column, (f) condensing said distillate with the lower boiling point to yield an alcohol-rich distillate, and (g) discharging said fraction with the higher boiling point as a bottom residue, and a processor therefor, thereby discharging to the outside the low COD-liquid alone and recovering useful substances such as drinkable alcohol, livestocks feed and antibiotic substances.

Abstract: An apparatus for vaporizing a liquid and condensing the vapor includes at least one chamber in which the liquid is vaporized and at least one chamber in which the vapor is condensed. The apparatus has a conveyor inlet channel preferably at one end of the vaporizing chamber, and a conveyor outlet channel preferably at the opposite end of the vaporizing chamber. A conveyor for moving items to be treated through the apparatus extends through the conveyor inlet channel into the vaporizing chamber and out of the vaporizing chamber through the conveyor outlet channel. The apparatus includes a heat emitting device in the vaporizing chamber for vaporizing the liquid therein, and a cooling device in the condensing chamber for condensing the vapor.

Abstract: A process for the nondegenerative distillation of C.sub.6 -C.sub.24 -fatty acids, of the type obtained by splitting natural fats and oils or by synthetic processes, such as for example the oxidation of paraffins, the crude product is thermally dried under reduced pressure, the dried and heated crude product is subjected to fractional evaporation in falling-film evaporators, optionally in the presence of superheated steam, and the various vapor fractions are deposited in condensers. The thermal drying process is conducted at a temperature of 60.degree.-80.degree. C. and a pressure of 90-100 mbars. The de-watered crude product is fractionated in a film-forming evaporator and, after distillation, passes to a rectification column which condenses the low boiling constituents as the main runnings.

Abstract: Improved process for the separation of a hydrocarbon-containing feedstream comprising monomer, comonomer and diluent into separate product streams which comprises subjecting the feedstream to two-stage distillation provided with a common accumulation zone wherein the condensate from the accumulation zone serves as the source of feed for the second distillation and reflux for the first distillation. In a specific embodiment, a feed comprising ethylene, 1-hexene, and isobutane is separated into separate streams of 1-hexene, ethylene and isobutane, and isobutane for recycle to polymerization.

Abstract: The invention relates to a vaporization and condensation process for the fractionation of mixtures by continuously heating, in a circulation circuit, a clean heat transfer gas which is subsequently injected into a mixture to be fractionated (16), of which at least one liquid fraction, which has separated off by vaporization, is condensed and collected while the heat transfer gas returns to the circulation circuit.

Abstract: An apparatus and method for vaporizing and recovering, by condensation, a composite liquid solution of at least two components having substantially different vaporizing temperatures. The apparatus includes at least one liquid condensate vaporizing chamber wherein the vapor of the lower vapor point component will be condensed from a vapor zone above the vapor zone of the vapor of the higher vapor point component. The apparatus further includes at least two weir or other means to define the vapor levels of each vaporized component and the condensing means for each component are disposed on the opposite side of the weir from the vapor zone.

Abstract: A process to recover acrylic acid or methacrylic acid by using a split quench process which allows acrylic acid or methacrylic acid to be recovered from the resulting aqueous solutions by a combination of solvent extraction and azeotropic dehydration that minimizes the amount of solvent required.

Abstract: An improved process for the preparation of urea from carbon dioxide and excess ammonia at elevated temperature and pressure. The urea solution from the urea synthesis zone is heated and stripped at an elevated pressure to decompose a portion of the ammonium carbamate contained therein and the ammonium and carbon dioxide containing off-gas produced is condensed in a first condensation zone. The stripped urea solution is heated at a reduced pressure in a decomposition zone to decompose a further portion of ammonium carbamate, and the ammonia and carbon dioxide containing off-gas thereby produced is condensed in a second condensation zone to form an aqueous ammonium carbamate solution.

Abstract: A process for the distillation and condensation of a multi-component liquid is described, the process being characterized by the utilization of a portion of the condensate in achieving increased separation of components of no-condensed vapor. In a principal embodiment, the overhead from a distillation column is cooled, condensing a portion thereof, and the condensed portion is accumulated in an accumulation zone. A first liquid stream is removed from the accumulation zone for reflux, while a second liquid stream is cooled, and then contacts, in a separate zone, the uncondensed portion of the overhead. The contacting absorbs and condenses components of the vapor, and the second liquid and absorbed components are collected in the accumulation zone.

Abstract: A process for the distillation and condensation of a multi-component liquid is described, the process being characterized by the contacting of a warm portion of the overhead vapor with a cool liquid portion of the overhead to achieve a higher accumulator liquid temperature. In a principal embodiment, a multi-component liquid is distilled, the overhead vapor is separated into major and minor portions, and the bulk of the major portion is condensed. Liquid is separated from the remaining vapor of the major portion, and the separated liquid is divided into major and minor fractions. The major fraction of liquid is collected in an accumulation zone, and is contacted in the accumulation zone with at least the bulk of the minor portion of overhead vapor. Vapor from the accumulation zone is contacted with the minor fraction of liquid in a contacting zone.

Abstract: A process for distilling and condensing a multi-component liquid is described, the process being characterized by the use of a portion of the uncondensed vapor in achieving more efficient heat utilization. In a principal embodiment, the multi-component liquid is distilled to produce an overhead vapor, and the vapor is condensed to produce a condensate and a partially cooled vapor. The partially cooled vapor is separated into major and minor portions, the bulk of the major portion is condensed to produce a condensation effluent, and the condensation effluent (comprising liquid or liquid and vapor) is contacted in a contacting zone with the minor portion of partially cooled vapor. The contacting produces a liquid which is collected in an accumulation zone.

Abstract: A process for distilling and condensing a multi-component liquid is described, the process being characterized by the use of a portion of uncondensed vapor in achieving more efficient heat utilization. In a principal embodiment, a multi-component liquid is distilled to produce an overhead vapor, the vapor is partially condensed, and the vapor-condensate is separated into a minor liquid fraction and a major vapor-liquid portion. The major vapor-liquid fraction is then separated into vapor and liquid, and the liquid therefrom is accumulated in an accumulation zone. The separated vapor is then contacted with the minor liquid fraction in a contacting zone, thereby absorbing the vapor and transferring its heat to the liquid fraction.

Abstract: Aldehydes are obtained from the gaseous product of the hydroformylation of olefinically unsaturated compounds using a rhodium catalyst by a process (cf. FIG. 2) in which(a) this gaseous product is introduced, without being cooled or depressured, into a distillation column D,(b) the top fraction from this column is cooled in a condenser K so that the greater part of the aldehydes contained therein is condensed,(c) the condensate is separated, in a separator A, into a gas phase and a liquid phase,(d) the gas phase from A, after waste gas has been separated off, is again brought to the hydroformylation pressure by means of a compressor P, and is returned to the reactor as a recycle gas,(e) the liquid phase from A is returned to D, and(f) the aldehydes are taken off from column D as liquid bottom products and/or as a vaporous side stream.

Abstract: A recycle water treatment system for separating oil vapor from steam recovering the oil and heat from the steam and destroys microorganisms and exotoxins which incorporates an inclined duct connected to a barometric condenser with a container for oil at the lower end of the condenser. Oil entrained in the steam is carried up the duct and over the barometric condenser. The steam heats the condenser water that is recovered while the entrained oil flows back down the duct into a recovery container. The condenser water-steam condensate mixture is maintained at about 180.degree. F. for a period of time sufficient to destroy microorganisms and exotoxins.

Abstract: Volatile reactants are heated under reflux in a reactor and form volatile reaction by-products which are continuously removed in a vapor effluent from a reflux column and partial condenser. The effluent, which entrains some of the reactants, is condensed in a first total condenser and is fed to a distillation apparatus for separation of the volatile reactants and by-products and return of the separated reactants to the reactor. Before the condensate reaches the distillation apparatus, it is temporarily stored in a receiver from which it is controllably fed to a pre-heater where it is evaporated and then fed as a vapor to the distillation column of the distillation apparatus for separation. The distillation column includes at one end a reboiler which retains the reactants. The other end of the distillation column is coupled to a second total condenser in which the volatile by-products are condensed and withdrawn through a cooler for disposal.

Abstract: Formaldehyde manufacture by oxidative-dehydrogenation of methanol over a silver or copper catalyst. Aqueous formaldehyde solution is obtained from the reaction and is stripped of methanol and water by a low energy process at relatively low temperature by means of recycled inert gas in a stripping column comprising at least about 1.5 theoretical transfer units for stripping methanol.

Abstract: A method and apparatus particularly suitable for the production of alcohol from fermentable substances such as grain. In this method, mash cooking, fermentation, and boiling are carried out sequentially in a single vessel. Boiling produces a first vapor rich in alcohol which is partially condensed to form a liquid condensate and a second vapor which is further enriched in alcohol. The liquid condensate is returned to the vessel and an alcohol product is recovered from the second vapor, preferably without the addition of external heat. Alcohol recovery is effected by passing the second vapor to a second vessel. Vapor from the second vessel is partially condensed to form a third vapor which is still further enriched in alcohol and a liquid condensate which is returned to the second vessel where it is contacted by the second vapor introduced thereto.

Abstract: The invention involves a process for substantially separating the components of mixtures of substances at least one of which is of low volatility while the other is of low or no volatility, the process using a compressed gas under supercritical conditions and an entrainer which increases the concentration of said mixture in the gaseous phase as well as the separation factor between the components to be separated. The process operates in two distillation zones the first of which substantially separates the components of low volatility in a process similar to a rectification process while the second distillation zone separates the top product of the first distillation zone from the gas with the aid of the entrainer which is condensed partially and in this state is passed in countercurrent to the gas carrying the separated component of low volatility.

Abstract: Pure acetone is recovered from a crude acetone vapor fraction removed overhead from a first column separating phenol and higher boilers as a bottom fraction from a cumene hydroperoxide cleavage reaction product by partially condensing the crude acetone fraction, returning the condensed portion of the crude acetone fraction to the first column as reflux, feeding the remaining portion as a vapor to an intermediate point in a second distillation column to which there is also fed continuously at a point above the acetone feedpoint a dilute aqueous solution of an alkali, removing from the base of the second column a residue fraction comprising compounds boiling above acetone, removing from a point in the second column intermediate; between the alkali feedpoint and the top of the column as a liquid sidedraw fraction pure acetone having a permanganate time (PT) greater than 4 hours, and removing from the top of the second column as a vapor fraction acetone having a PT less than that of the sidedraw fraction, condens

Abstract: A method for the recovery of heat and easily evaporable components from hot gases in which a liquid flowing downwards along heat exchanger surfaces is simultaneously heated indirectly, the hot gases are fed into the lower section of a gas space, blast gas containing evaporable components is removed at the upper section of the gas space, and a condensate derived from the hot gases is removed at the bottom of the gas space, comprising further bringing the blast gases into one or several indirect heat exchange contacts with the liquid, in successive additional gas spaces, recovering condensate accumulated at the bottoms of these additional spaces, and withdrawing the blast gases from the last additional gas space.

Abstract: A distillation/evaporation/drying apparatus wherein alcohol is removed by a dry, warm carrier gas from an alcohol-containing slurry from a fermenter. Carbon dioxide from the fermenter is used as the carrier gas and is suitably dried, warmed and recycled into contact with the slurry to assist in removing alcohol therefrom. The apparatus includes a reflux section to upgrade the alcohol content of the carrier gas.

Abstract: A process for the substantially complete removal of acid gases and ammonia from aqueous solutions is disclosed, which comprises a two stage distillation operation wherein the pressure in the first distillation stage is substantially less than the pressure in the second stage, the ammonia concentration in this stage decreases downwardly so that an aqueous bottoms stream has a pH less than 8, this aqueous bottoms stream is treated with alkali and then distilled in the second stage. A portion of the aqueous bottoms can be vaporized by indirect heat exchange with vapors evolving from the second stage. The improvement lies in adding ammonia to the overhead vapor from the first stage to reduce corrosion of the condenser and preferably, the amount of vapor condensed is controlled to further minimize corrosion.

Abstract: A high melting, high boiling organic compound is easily and stably purified by continuously supplying the molten organic compound to a rectification zone under a subatmospheric pressure and continuously distilling off and recovering vapors from the top of the rectification zone, while continuously withdrawing bottoms containing higher boiling impurities and/or involatile impurities than the desired compound from a reboiling zone at the bottom of the rectification zone to the outside of rectification system by means of a barometric leg, without any pretreatment of removing lower boiling impurities therefrom before the rectification, and without disturbing a pressure balance in the rectification system.

Abstract: The invention relates to a process for the isolation of chloroacetaldehyde which is obtained as a by-product during the synthesis of acetaldehyde from ethylene and air in an aqueous palladium/cupric chloride solution by the 2-stage process. The mixture to be worked-up to chloroacetaldehyde is taken from the acetaldehyde distillation column and transferred to a distillation and extraction system, where it is fractionally condensed. The chloroacetaldehyde-containing fraction is extracted with water and the aqueous extract is subjected to purification distillation.

Abstract: A method for the removal of aromatic hydrocarbon from mixtures containing non-aromatic hydrocarbon by liquid-liquid extraction and extractive distillation is described. Isoenthalpic expansion of the rectification column bottom solvent stream and addition of water to the selective solvent can be used to reduce heat consumption.

Abstract: A process for the manufacture of 4,4'-diphenylmethane diisocyanate and a mixture of diphenylmethane diisocyanate isomers containing a controllable amount of uretdione and hydrolizable chlorine which comprises feeding crude MDI to an evaporator, condensing a head fraction in two stages in the presence of an inert gas, feeding the first stage condensate to a distillation column, producing a mixture of diphenylmethane diisocyanate isomers as an overhead, producing 4,4'-diphenylmethane diisocyanate as a side draw, and condensing each of the overhead and side draw in two stages in the presence of an inert gas.

Abstract: A process for the multistage condensation of an overhead fraction is disclosed. The process employs a single accumulation zone for at least two stages of the condensation, the accumulation zone being characterized by separate accumulation sections formed by a barrier which provides, at or near its bottom, limited liquid flow between the sections.

Abstract: An improved solvent recovery process comprising distilling soiled solvent in a main still and conducting hot solvent vapor through a heat exchanger associated with a tank in which an azeotropic mixture of water and soiled solvent is maintained, which mixture boils at a temperature lower than the boiling point of the solvent alone. A series of tanks feed soiled solvent to the azeotropic mixture tank and then to the main still, and heat exchangers fed by the vapor from the main still and the vapor from the azeotropic mixture tank pre-heat the soiled solvent. Automatic control of water injection into the azeotropic mixture tank in dependence upon the temperature of conductivity of the tank contents maintains the composition of the azeotropic mixture, the injected water being taken from separators which separate water from condensate of the main still and azeotropic mixture tank vapors.

Abstract: Volatile reactants are heated under reflux in a reactor and form volatile reaction by-products which are continuously removed in a vapor effluent from a reflux column and partial condenser. The effluent, which entrains some of the reactants, is condensed in a first total condenser and is fed to a distillation apparatus for separation of the volatile reactants and by-products and return of the separated reactants to the reactor. Before the condensate reaches the distillation apparatus, it is temporarily stored in a receiver from which it is controllably fed to a pre-heater where it is evaporated and then fed as a vapor to the distillation column of the distillation apparatus for separation. The distillation column includes at one end a reboiler which retains the reactants. The other end of the distillation column is coupled to a second total condenser in which the volatile by-products are condensed and withdrawn through a cooler for disposal.

Abstract: Coronene deposits are removed from a heat exchange zone of the reforming process by recycling a portion of the normally liquid reformate to the heat exchange zone to dissolve the coronene deposits.

Abstract: Contaminant substances having high biochemical oxygen demand, foul odors, etc., are often carried by vapors to be condensed in industrial processes. Certain of these contaminants are more volatile than the primary constituent of the vapor to be condensed. The invention concerns a process and apparatus for separating most of the more volatile contaminants so that separate streams of condensate are produced, one of which is relatively clean while the other stream, though considerably smaller in volume, carries most of the contaminants. A plate type surface condenser having a barrier on the condensing side which prevents the passage of contaminants into a stream of relatively clean condensate is disclosed. In case several different streams of condensate are to be separated, the condenser apparatus has several sections arranged in series.

Abstract: Coronene deposits are removed from a heat exchange zone disposed in two parallel trains of heat exchangers in a reforming process by reducing the flow of reforming zone effluent in one of the trains of heat exchangers sufficiently to effect condensation of a portion of the reforming zone effluent in said one train of heat exchangers where the coronene is deposited while simultaneously increasing the flow of reforming zone effluent in the second train of heat exchangers. Control means are provided in each of the heat exchange trains.

Abstract: Coronene deposits are removed from a heat exchange zone of a reforming process by operating the reforming zone at conditions such that at least a portion of the reformer effluent condenses in the heat exchange zone where the coronene deposit occurs.

Abstract: A diffusion pump capable of separating impurities from its pump fluid during operation is disclosed. Skimming drains are provided in the pump's boiler for periodically skimming the evaporative surface of the working fluid. This eliminates nearly all contaminants of higher molecular weight than the pump fluid. In the foreline of the pump, a series of peripheral gutters are provided for trapping, separating and draining off condensates. The gutters facilitate the removal of impurities of lower molecular weight than that of the pump fluid. Means are also provided for further removing trace quantities of residual volatile impurities which tend to backstream up the diffusion pump barrel. The highly purified pump fluid allows for a more vigorously working evaporative surface, thereby increasing the throughput of the diffusion pump. Together with the elimination of volatile impurities from the pump barrel, this facilitates the attainment of significantly higher ultimate chamber vacuum.

Abstract: Steam carrying fatty acids is contacted in a barometric condenser with a cooling medium comprising a fatty acid having between six and eighteen carbon atoms to produce a liquid organic phase containing the fatty acids which were entrained in the steam, and an aqueous phase, such phases being readily separated by decantation. After separation of the phases, a portion of the organic phase is used for the cooling medium.

Abstract: A fractionation process wherein a fractionation column is maintained at a subatmospheric pressure through the use of a steam-jet ejector. Water drawn off the overhead receiver of the fractionation column is vaporized by indirect heat exchange to form the moderate pressure steam charged to the ejector. The effluent of the ejector is passed through a condenser, and the resultant condensate is recycled to the overhead receiver by admixture with the overhead vapor stream of the fractionation column. The disposal of hydrocarbon-contaminated aqueous overhead liquid is thereby minimized.

Abstract: A diffusion pump capable of separating impurities from its pump fluid during operation is disclosed. Skimming drains are provided in the pump's boiler for periodically skimming the evaporative surface of the working fluid. This eliminates nearly all contaminants of higher molecular weight than the pump fluid. In the foreline of the pump, a series of peripheral gutters are provided for trapping, separating and draining off condensates. The gutters facilitate the removal of impurities of lower molecular weight than that of the pump fluid. Means are also provided for further removing trace quantities of residual volatile impurities which tend to backstream up the diffusion pump barrel. The highly purified pump fluid allows for a more vigorously working evaporative surface, thereby increasing the throughput of the diffusion pump. Together with the elimination of volatile impurities from the pump barrel, this facilitates the attainment of significantly higher ultimate chamber vacuum.

Abstract: Acrolein and other light ends are removed from the effluent of a process for the production of acrylic acid by the vapor phase catalytic oxidation of acrolein or an acrolein precursor, such as propylene, by passing the effluent to the base of a fractionation tower and contacting such with the descending stream of liquid within the tower so as to partially condense the condensibles in the effluent, a portion of the liquid bottoms being recycled to the upper portions of the tower and a portion withdrawn as crude acrylic acid product. Acrolein is removed overhead.

Abstract: In an oxidation process for converting methacrolein to methacrylic acid, methacrylic acid is recovered by cooling and condensing the effluent from the oxidation, followed by azeotropic distillation of the condensate with a suitable solvent, such as methyl n-propyl ketone. The condensed effluent contains methacrylic acid and water as the major components along with by-product acetic acid, a minor amount of unreacted methacrolein and impurities. Substantially dry crude methacrylic acid is separated as a bottom product from the azeotropic distillation and an azeotrope of water and the solvent is taken overhead and condensed. After condensation, solvent-rich and water-rich phases form and are separated. The solvent-rich phase is returned to the distillation column as a reflux, while the water-rich phase is sent to a stripping column for recovery of residual solvent. Water is withdrawn from the bottom of the stripping column and recycled or discarded, as desired.

Abstract: The process of separating water and wash oil from a gaseous feed stream of water vapor, wash oil and light oil involving (a) directing the gaseous feed stream in an upward direction and in contact with a cooling solid surface such that a temperature gradient of the gaseous stream is produced such that the temperature of the gaseous stream is highest at the bottom of the cooling solid surface such that gaseous components of the gaseous stream having the highest boiling temperature condense onto the lower portions of the cooling solid surface and wherein the lower boiling components of the gaseous stream condense onto the solid surface at higher portions on the solid surface to thereby form a liquid film on the solid surface, which film then runs downward onto the lower portions of the solid surface to thereby inhibit deposits from adhering to these lower portions of the solid surface; (b) withdrawing a gaseous stream containing a major portion of light oil; and (c) withdrawing a liquid condensate which contain

Abstract: The temperature of the reflux fed to a fractionating tower is increased after the reflux enters the tower and before it passes onto the reflux return tray by passing the reflux through an atomizer in the fractionating tower above the reflux return tray to produce a downfalling spray of liquid droplets; collecting the droplets on a reflux pan located between the atomizer and the reflux return tray, the reflux pan being designed to allow the passage of hot vapors rising from the reflux return tray; and passing the collected liquid from the reflux pan onto the reflux return tray. The distance between the reflux pan and the atomizer is such as to allow the downfalling droplets to absorb sufficient heat from the hot rising vapors so that the temperature of the reflux liquid collected on the reflux pan is increased to a desired value.