Abstract: An apparatus for dissolving oil or PCB which exists in the electrical insulation of parts to be cleaned, wherein a solvent is evaporated during a heating phase by an evaporator located with the parts in an autoclave. The solvent vapor condenses on the parts and penetrates into the electrical insulation to form an oil or PCB-solvent mixture. The apparatus provides for a plurality of intermediate pressure reductions which are carried out in the autoclave, and during each intermediatre pressure reduction the solvent is simultaneously evaporated from the oil or PCB-solvent mixture, directly from the autoclave. That is, during each of the pressure reductions, the solvent supply is discontinued and the mixture circulated through a circulating line. Following the completion of each intermediate pressure reduction, the pure oil or PCB present in a condensate vessel is pumped out by an intermediately located feed pump through a connecting line and into a reservoir.

Abstract: A process for the production of pure dimethylether by feeding the dehydration product from a dimethylether-synthesis reactor into a distillation column for the production of pure dimethylether at defined trays of this column and withdrawal of pure dimethylether and a fraction containing contaminations at defined trays of the same column, whereby in addition washing liquids and bases can be added.

Abstract: In a vacuum distillation process a feed stream is supplied to a furnace and a heated feed stream containing vapor and liquid is passed from the furnace into a distillation column operating at a subatmospheric pressure. Vapor is allowed to rise inside the distillation column. The rising vapor is contacted with a de-entrainment means to remove entrained liquid from the rising vapor. Wash liquid is sprayed on the de-entrainment means and subsequently passed from the distillation column to a collection vessel. The wash liquid is cooled and then withdrawn from said collection vessel.

Abstract: Improved hydrocarbon vacuum distillation process wherein the process steps include introducing a feed which contains liquid hydrocarbons and vaporous hydrocarbons into an inlet section (3) of a distillation column (1) operating at a subatmospheric pressure, removing liquid from a bottom section (6) of the distillation column (1), allowing vapor to pass through three condensation sections (13b, 13a and 13) arranged above each other in the distillation column (1) between the inlet section (3) and a top section (8), removing vapor from the top section (8), spraying into each condensation section (13, 13a and 13b) cooled liquid, and removing liquid from each condensation section (13, 13a and 13b), wherein the cooled liquid which is sprayed into each condensation section (13, 13a and 13b) includes liquid removed from that condensation section (13, 13a and 13b), and wherein the cooled liquid which is sprayed in the uppermost condensation section (13) further includes liquid removed from the condensation sections (1

Abstract: A process for the concentration of ethylene oxide in an impure solution thereof including adding the solution and steam to a distillation column, recovering the gaseous stream therefrom containing ethylene oxide, and progressively condensing the steamed solution in at least two heat exchangers arranged in series, with the absolute pressure of the distillation column and of the exchangers being between about 1.5 and 6 bars and the temperature of the cooling fluid of the last exchanger being between about 5.degree. C. and a maximum temperature 5.degree. C. below the temperature of condensation of pure ethylene oxide at the pressure used.

Abstract: An integrated continuous processes for concentrating "weak" nitric acid and concurrently reconcentrating the spent dehydrating agent used to break the nitric acid azeotrope to obtain "strong" nitric acid, the processes involving direct coupling of the nitric acid concentration with the reconcentration of the spent dehydrating agent so that less energy input is required. The major proportion of the feed "weak" nitric acid is vaporized before being fed countercurrently into a column to contact a large volume of the dehydrating agent, this vaporization being one of the two major sources of energy input, the second being through the reboiler at the bottom of the column. Energy input is balanced by energy rejection through condensation of strong nitric acid vapor and water vapor.

Abstract: An apparatus and process for separating a more volatile substance from a liquid in which it is dissolved by vacuum means. The apparatus has a perforated inner casing having a plurality of sub-stages which contain packing material to provide a tortuous path of interstices for the liquid to flow through; an outer casing surrounds the inner casing to define an evacuating space between the outer and inner casing and vacuum means to create a vacuum in the evacuating space which communicates with the sub-stages through the perforations in the inner casing. The vacuum means also acts to pull off the more volatile substance.

Abstract: In order to dissolve oil or PCB which exists in the electrical insulation of parts to be cleaned, a solvent is evaporated during a heating phase by an evaporator located with the parts in an autoclave. The solvent vapor condenses on the parts and penetrates into the electrical insulation to form an oil or PCB-solvent mixture. In the heating phase, a plurality of intermediate pressure reductions are carried out in the autoclave, and during each intermediate pressure reduction the solvent is simultaneously distilled out of the oil or PCB-solvent mixture, directly from the autoclave. That is, during each of the pressure reductions, the solvent supply is discontinued and the mixture circulated through a circulating line. Following the completion of each intermediate pressure reduction, the pure oil or PCB present in a condensate vessel is pumped out by an intermediately located feed pump through a connecting line and into a reservoir.

Abstract: Excess amounts of a pure form of acrylonitrile are reacted with other reactants in the production of various compounds such as 2-acrylamido-2-methyl propane sulfonic acid. Accordingly, large amounts of acrylonitrile remain unreacted and present with other contaminants. The present invention is directed toward the purification of such unreacted acrylonitrile and the purified acrylonitrile obtained from such a purification process. The purification is carried out by treating the unreacted acrylonitrile with a base and removing salts formed. The treated material is fed to a heat exchanger which heats the material preferably under vacuum to about 120.degree. F. and provides a heated fluid material. This heated fluid material is pumped to a lower area of a distillation tower which is maintained under vacuum and includes a plurality of distillation trays.

Abstract: For the preparation of an ether, e.g., tertiary amyl methyl ether, an olefin-containing feed stream is catalytically etherified with an alcohol, e.g., methyl alcohol. The etherification product is fractionally distilled into an overhead fraction containing essentially unreacted, light hydrocarbons and unreacted alcohol and into a bottoms fraction containing essentially the desired ether. The overhead fraction is condensed and cooled to resultant immiscible phases, of which one contains essentially the alcohol and the other contains essentially the hydrocarbons, are removed separately from each other. Water may be added to the overhead stream to facilitate the formation of the two liquid phases.

Abstract: This invention relates to a process for preparing 2,2-bis(4-hydroxyphenyl)propane, e.g. bisphenol A and particularly to a process for preparing high quality bisphenol A with good workability by distilling the intermediate adduct of bisphenol A and phenol.The adduct of bisphenol A and phenol is fed to a distillation column. Phenol is recovered from the top of the column and bisphenol A is obtained from its bottom. In this distillation process, the adduct of bisphenol A and phenol is added with a part of recycled bottom liquid. Consequently troubles such as plugging of the distillation column are prevented, continuous operation becomes possible for a long period of time and high quality bisphenol A can be steadily obtained.

Abstract: This invention is a process for purifying crude acetone obtained by cleavage of cumene hydroperoxide, said crude acetone containing aldehyde impurities and appreciable amounts of unreacted cumene, by fractionally distilling the acetone in a multiple plate distillation column, said process comprising: continuously feeding crude acetone; continuously feeding a dilute aqueous solution of an alkaline material at a point above the crude acetone feed point; and controlling the temperature profile of the column by adjusting the amount of liquid acetone removed in step (c) to maintain a preselected temperature on a plate in the region between the crude acetone feed point and the alkaline material feed point.

Abstract: An improved method and apparatus for de-entraining liquid droplets from a vaporous stream as it leaves a flash zone of a separation tower. The removal of the droplets is accomplished by a chimney which directs vapor flow through two direction changes of about 180.degree. each. The chimney comprises a riser and hat which have an annulus between them. The cross-sectional area of the annulus is less than that of the cross-sectional area of the riser, so the momentum imparted to the entrained droplets drives them downwardly while the lighter vapor undergoes the second direction change and continues upwardly. The chimney may further reduce entrainment by having an extended portion of the riser below a plate and a lip attached to the inside perimeter of an opening of the riser above the tray. Preferably a lower portion of the riser has a larger cross-sectional area than an upper portion of the riser.

Abstract: A problem has been identified which made it difficult, if not impossible, for the prior art to operate a reboiler in the mist flow regime. The invention which overcomes this problem is to provide a chamber to establish equilibrium between the vapor portion and the liquid portion of the reboiler effluent prior to introducing equilibrated vapor into the bottom of the distillation column. The invention is particularly useful for minimizing degradation of thermally sensitive materials.

Abstract: The present invention provides a process for distillation of styrenes which can be stably operated without loss of energy saving effect, by leading a part or all of low boiling point component vapor from the top to a compressor to use as a heat source for a reboiler and returning the low boiling point components condensed in the reboiler or a mixture of the condensate and a part of the uncondensed vapor to a recycling line of a distillation column.

Abstract: A distillation method and apparatus which comprises (a) a distillation zone adapted for the countercurrent contact of liquid and vapor, (b) a reboiler feed liquid compartment (c) means for directing distillation zone liquid into the reboiler liquid feed compartment, (d) a thermosyphon reboiler for partial vaporization of liquid thereto to produce reboiled vapor and liquid flows, (e) a conduit for the flow of liquid from the reboiler liquid feed compartment to the reboiler, (f) a reboiler return liquid compartment, (g) a conduit for the flow of reboiled liquid from the reboiler to the reboiler return compartment, (h) a conduit for the flow of reboiled vapor from the reboiler to the distillation zone, (i) means for communication of liquid by gravity flow between the reboiler feed compartment and the reboiler return compartment to provide substantially equal liquid levels in the two reservoirs, (j) a distillation zone liquid product compartment, (k) means for overflow of liquid from the reboiler return compartme

Abstract: A liquid distillation apparatus provides recirculating flow of unevaporated liquid and recovery of energy from the liquid circulation. Liquid columns in communication with each other are provided differing liquid levels to enhance circulation of the liquid, and to provide efficient operation of the apparatus. Aeration is used to raise the level of the liquid in one of the liquid columns as well as to improve vapor generation for use in a condenser. The two liquid columns are separated from one another except for a connection at the tops and bottoms thereof to permit recirculation of the liquid. The aeration system may be operated by energy recovered from the circulating liquid.

Abstract: Disclosed is a process for recovering a virtually water-free amine from an amine acid salt thereof. The process comprises a unique combination of phase separation stages practiced under mild heating and distillation stages. An amine product containing less than 0.2% water can be achieved by the present process. The feedstock for the process suitably is an acid scrub liquor used to scrub amine from a vapor stream thereof which has been used in a cold-box molding process in the foundry industry or in the cure of vapor permeation curable coatings in the coatings industry.

Abstract: Ethylene glycol is purified, particularly for fiber-grade applications, by removal of the residual ethylene carbonate from which the glycol was derived. The effluent from a reactor in which ethylene carbonate is hydrolyzed to ethylene glycol is distilled to produce a lower-boiling fraction comprising substantially ethylene glycol and water and a higher-boiling fraction comprising substantially ethylene glycol, higher glycols, and concentrated in hydrolysis catalyst. The higher-boiling fraction is recirculated to reflux against the lower-boiling product, thereby essentially completing the hydrolysis of unreacted ethylene carbonate thereby reducing the ethylene carbonate content of the ethylene glycol to very low levels suitable for fiber-grade applications.

Abstract: This process separates less volatile contaminates from thermal power recovery systems utilizing a volatile working fluid in a cyclic closed system; such a system may comprise a reservoir, a pump, a heater, a separator, a throttle device, a turbine and a condenser. The purification can be accomplished during start-up, shut-down or periods of low power generation. The contaminant is separated from the working fluid in the separator in which the temperature and pressure correspond to a dew-point substantially above that of a sample of uncontaminated working fluid. To achieve this condition, the normal flow of liquid from the reservoir to the heater is reduced and the heater and throttle device are correspondingly adjusted. The condensed contaminant is removed from the separator while substantially all of the working fluid which has been vaporized is passed on through the throttle device to the turbine.

Abstract: A distillation method and apparatus which comprises (a) a distillation zone adapted for the countercurrent contact of liquid and vapor, (b) a reboiler feed liquid compartment (c) means for directing distillation zone liquid into the reboiler liquid feed compartment, (d) a thermosyphon reboiler for partial vaporization of liquid thereto to produce reboiled vapor and liquid flows, (e) a conduit for the flow of liquid from the reboiler liquid feed compartment to the reboiler, (f) a reboiler return liquid compartment, (g) a conduit for the flow of reboiled liquid from the reboiler to the reboiler return compartment, (h) a conduit for the flow of reboiled vapor from the reboiler to the distillation zone, (i) means for communication of liquid by gravity flow between the reboiler feed compartment and the reboiler return compartment to provide substantially equal liquid levels in the two reservoirs, (j) a distillation zone liquid product compartment, (k) means for overflow of liquid from the reboiler return compartme

Abstract: A C.sub.4 and/or C.sub.5 olefinic hydrocarbon cut, containing dimethyl ether and water as impurities, in a relative proportion of dimethyl ether to water of at most 5:1, is purified in a distillation zone where it is introduced at an intermediate level, distant from the top or from the bottom thereof by at least 3 theoretical plates, optionally with a stripping gas, and separated into a overhead fraction comprising an aqueous liquid phase and a hydrocarbon liquid phase at least partially recycled as reflux to the upper part of the distillation zone, and a bottom fraction formed of the purified C.sub.4 and/or C.sub.5 olefinic cut.

Abstract: Disclosed is a process for recovering a virtually water-free amine from an amine acid salt thereof. The process comprises a unique combination of phase separation stages practiced under mild heating and distillation stages. An amine product containing less than 0.2% water can be achieved by the present process. The feedstock for the process suitably is an acid scrub liquor used to scrub amine from a vapor stream thereof which has been used in a cold-box molding process in the foundry industry or in the cure of vapor permeation curable coatings in the coatings industry.

Abstract: A method and apparatus for high volume distillation of impure liquid, particularly of binary mixtures of relatively low boiling organic substances and water, comprises fractionally distilling the impure liquid to form a vapor of a low boiling organic substance; compressing the vapor; passing at least a portion of the compressed vapor through a vapor composition adjustment zone wherein the organic substance may catalytically or otherwise react or merely stabilize following compression; compressing the vapor exiting the adjustment zone to form a recompressed vapor; cooling the recompressed vapor in heat transfer relation with the impure liquid whereby the vapor at least partially condenses, transferring sufficient heat to the impure liquid for evaporating the liquid and to form the aforementioned low boiling organic vapor; and collecting the condensed low boiling organic vapor.

Abstract: A process for producing an unsaturated nitrile with saved energy by which the bottom stream from a recovery column is used as the heat source for at least one distillation column in the process and thereafter used to pre-heat a recovery column feed withdrawn from the bottom of an absorption column, characterized in that the bottom stream of the absorption column is previously heated by at least one source of waste heat in the process, the source being selected from (1) the circulating water in the quenching column, (2) the overhead vapor of the absorption column, (3) the overhead vapor of a dehydration column and (4) the overhead vapor of a product column.

Abstract: In a process for recovering pure methylal from methanol-methylal mixtures, which can optionally contain still further compounds, the separation conducted in a rectification device comprising two rectifying columns. In the first rectifying column, the mixture to be separated is rectified under a pressure lower than that in the second column, into a methylal-rich, methanol-poor distillate, and into a practically methylal-free, methanol-rich sump product. The methylal-rich distillate of the first rectification is then separated in a second rectifying column, operated under a higher pressure than the first rectification column, into a compound stream containing methanol and methylal, which is then recycled to the first rectifying column, and into pure methylal as the sump product.

Abstract: Purification of cuprous chloride is accomplished by distillation wherein cuprous chloride is recovered as the overhead product, and substantially all of the silver chloride and other impurities present report to the bottoms. Typical impurities in copper ore leach liquors include chlorides of silver, calcium, arsenic, bismuth, iron, nickel, lead, antimony, selenium, tellurium, silicon, mercury, manganese, tin, aluminum, magnesium, chromium, cobalt, cadmium, molybdenum, zinc and titanium, most of which may be excluded in large part by crystallization of cuprous chloride. Measurable amounts of these impurities, however, report to the crystals, and silver tends to co-precipitate with the copper in major amounts. Distillation accomplishes a high degree of copper-silver separation and substantial elimination of other impurities from the copper.

Abstract: A process for the isolation of hydroquinone, pyrocatechol, phenol and carboxylic acid from the reaction mixture containing the same such as one obtained by reaction of phenol with percarboxylic acid is disclosed. The reaction mixture is fed to a first rectification column and subjected to distillation whereby there is obtained a bottoms product containing pyrocatechol, hydroquinone and phenol. The top product is largely condensed and recycled, there being withdrawn from the top of the rectification column a mixture comprising phenol and carboxylic acid. The phenol and carboxylic acid mixture are continuously fed to a second rectification column where carboxylic acid is separated from phenol and substantially pure phenol is withdrawn from the stripping section and/or bottom of the second rectification column.

Abstract: Crude acetonitrile is purifed to 99+ weight percent by a continuous distillation procedure.

Abstract: A process is disclosed for the recovery of a cumene/alpha-methylstyrene fraction from a mixture thereof with phenol and water. Said mixture is introduced into a fractionation column at conditions to separate an overhead fraction comprising cumene and alpha-methylstyrene and a phenol bottoms fraction. A vapor stream comprising cumene, alpha-methylstyrene and a phenol-water azeotrope is withdrawn from an intermediate level of said column and condensed to form an organic phase and an aqueous phase comprising phenol. The latter is discharged, and the former is recycled to the column. The overhead fraction thus requires substantially less caustic to neutralize the residual phenol container therein.

Abstract: A process for distilling ammoniacal solutions is disclosed comprising the utilization of two distillation columns operating at different pressures, the ammoniacal solution to be distilled being sent--after being mixed with the ammoniacal vapors flowing from the top of the column operating at the lower pressure--to the column operating at the higher pressure, from the bottom of which the partially distilled ammoniacal solution is sent to the column operating at the lower pressure; the liquid ammonia being recovered at the top of the column operating at the higher pressure while the residual ammoniacal solution is withdrawn from the bottom of the column operating at the lower pressure.

Abstract: An improved distillation method and apparatus are provided for recovering hydrous ethanol from fermentation or synthetic feedstocks. Substantial energy savings are realized by utilizing a pair of stripper-rectifier towers in which overhead vapors from one tower operating at a higher pressure supply the heat required for the other tower operating at a lower pressure and by preheating the feedstock in multiple heat exchange steps. The feedstock is split into two portions of unequal size, the larger portion being supplied to the higher pressure tower and the smaller portion to the lower pressure tower.

Abstract: Process for isolating methyl tert-butyl ether contained in the reaction product of methanol with a C.sub.4 hydrocarbon cut containing isobutene, comprising fractionating said reaction product by introducing it at an intermediate point of a distillation zone, recovering methyl tert-butyl ether at the bottom thereof and, at the top thereof, a mixture of C.sub.4 hydrocarbons with methanol which is washed with water and condensed and wherefrom is separated a condensed C.sub.4 hydrocarbon fraction, a portion of which is fed back as reflux to the top of the distillation zone and another portion discharged, and separating the remaining water-methanol mixture by distillation.

Abstract: A process for recovering pure benzene from hydrocarbon mixtures containing the same and non-aromatic compounds which are gaseous and difficultly condensible is described in which the feedstock is fed to an initial distillation column operated at atmospheric or sub-atmospheric pressure. Overhead comprising benzene and non-aromatics is obtained and a portion thereof condensed. The condensible material is in part returned to the distillation column and in part subjected to extractive distillation to recover pure benzene. Those components which did not condense, i.e. the non-condensible and difficultly condensible components and entrained aromatics are fed to a reflux vessel such as a scrubber, stripper, or the like for recovery of any benzene or other valuable components which might be soluble in a selective solvent and used for such recovery. The selective solvent can be the same solvent used for the extractive distillation.

Abstract: A process for the separation of isobutane from an alkylation reaction zone hydrocarbon effluent stream comprising isobutane, n-butane, propane and alkylate is disclosed. The hydrocarbon effluent stream is charged to an isostripper column. An isobutane vapor stream from the column is condensed in indirect heat exchange with the lower liquid stream from said column comprising n-butane. The lower liquid stream is flashed in indirect heat exchange with said vapor stream at conditions to provide a vapor phase, said vapor phase being compressed and recycled to said column at a temperature to promote vapor formation therein.

Abstract: A process of recovering an n-hexane product which is free from aromatic compounds by extractive distillation from a mixture of aromatic and non-aromatic compounds. The mixture is fed to and distilled in a first distillation column, from which a benzene-containing sump product and the overhead product consisting of non-aromatic compounds are withdrawn. The distillate is laterally withdrawn above the feeding point of the feed mixture and transferred to the upper portion of a second distillation column. The hexane cut is withdrawn as sump product from the second distillation column and fed to an extractive distillation column approximately in the middle thereof and is extracted in the extractive distillation column with a selective solvent which is fed above the feeding point of the hexane cut consisting of the sump product of the second distillation column. The sump product containing the selective solvent is withdrawn from the extractive distillation column and the overhead thereof vapors are condensed.

Abstract: The present invention relates to a method of purifying readily polymerizable high boiling vinyl monomers, in particular the acrylates and methacrylates of alkylene oxides and their ether and ester derivatives to obtain pure water white esters. The process involves flash evaporation of the preheated esters followed by condensation in the presence of polymerization inhibitors under specific conditions. The purified esters thus produced find use either as such or in the form of their copolymers in coatings, enamel paints, weather resistant finishes, adhesive compositions, as plasticizers, as lubricants for cellulose films and fibers, in magnetic tape recording media and as oil additives.

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 process for converting butane to acetic acid wherein a mixture containing butane, molecular oxygen, acetic acid and cobaltic ions is continuously passed through a reaction zone under elevated temperatures and elevated pressures while maintaining therein a partial pressure of molecular oxygen of about 0.6 to about 15 pounds per square inch (0.04 to about 1.1 kilograms per square centimeter).

Abstract: Acetic acid containing very minor amounts of iodine, either as I.sup.-, free iodine, or alkyl iodide, or all of these, is purified by fractionation in a single column with an acid product containing 20 parts or less of iodine per billion parts of acid (ppb) being withdrawn as a liquid sidedraw from said column. Generally, more than one column is required for obtaining an acid product of such extremely high purity. The process is particularly applicable for purification of acetic acid made by the carbonylation of methanol using a catalyst system formed on the mixing of a rhodium or iridium component and an iodine component notably hydrogen iodide or an alkyl iodide such as methyl iodide.

Abstract: A low temperature purification system is provided which is particularly adapted for use to mechanically purify in a continuous operation solutions containing solids and dissolved substances. The purification system includes a solution supply means, and a centrifugal vacuum evaporator to which the solution to be purified is fed. Drive means is operatively connected to the evaporator for subjecting the solution within the evaporator to centrifugal acceleration and causes the solids in the solution to be displaced outwardly of the axis of rotation of the solution and the liquid of the solution to be displaced inwardly toward the axis of rotation. Outlet means is embodied in the evaporator for discharging the solids therefrom. The liquid as it is being displaced inwardly is simultaneously subjected to a reduced pressure to produce vapor which is conducted to a condenser means wherein the vapor is condensed to a substantially pure liquid.

Abstract: A process is provided for recovering hexane from the mixed recycle stream from a plurality of ethylene polymerization reactors. The recycle stream containing hexane and periodically vinyl acetate and/or an alkyl acrylate admixed with vinyl acetate to provide a mixed feed stream containing at least 45% by weight vinyl acetate. This feed stream is distilled at atmospheric pressure and all of the hexane is recovered as an overhead azeotrope containing about 57% hexane. The overhead fraction is redistilled at a superatmospheric pressure of at least 4 atmospheres in a second column. The overhead fraction of the second column will be enriched in vinyl acetate and pure hexane is recovered as a bottoms fraction from the second column. The vinyl acetate and/or alkyl acrylate contained in the bottoms fraction of the first column is recovered by atmospheric distillation in a third column.