Abstract: A process for the evaporation of an available warm or hot liquid under a vacuum by applying a pressure drop thereon initiating flash-down evaporation, and followed by further flash-down evaporation under an applied pressure gradient whereby the residual liquid is raised by the vapor produced to an elevation sufficient for subsequently discharging the residual liquid from vacuum without a pump; and by separating the vapor phase from the residual liquid phase before condensing the vapor produced into distilled liquid.

Abstract: Inhibition of the formation of unsaturated carbon compounds during the heating of 141b involving the addition of various inhibitors such as butylene oxide and/or the use of a vessel made of a nickel alloy.

Abstract: Inhibition of the formation of unsaturated carbon compounds during the heating of 141b involving the addition of various inhibitors such as dialkylhydroxylamine and/or the use of a vessel made of a nickel alloy.

Abstract: A method and apparatus for recycling and recovering potentially explosive solvents includes providing a contaminated solvent to a distillation tank, vaporizing the solvent in the distillation tank, thereby producing solvent vapor, condensing the solvent vapor, and adding a free radical scavenger substance to the distillation tank during the heating step. The vapor is then condensed and collected in a clean solvent tank where additional free radical scavenger substance is added to the clean solvent tank. Preferably, contaminated solvent is introduced into the solvent recovery system by providing contaminated solvent into contaminated solvent tank which is connected to the distillation tank, and an oxygen displacer substance is provided to the contaminated solvent tank and the clean solvent tank so as to minimize the amount of free oxygen in the tanks.

Abstract: A process for distilling ethylene oxide out of a mixture including ethylene oxide in a column at an absolute pressure of from 2 to 10 bar and a temperature of 20 to 180.degree. C. by withdrawing pure ethylene oxide in the liquid or gaseous state overhead or via a sidestream in the rectifying section of the column includes effecting the distillation in a column having on its inside a plurality of successive zones of structured sheet-metal packing or dumped beds of packing elements, these zones being assigned one or more extinguishing systems on the outside of the column.

Abstract: A method of inhibiting calcium carbonate scaling in a multi-stage evaporation plant of black liquor by heat-treating calcium-containing liquor includes a first stage wherein the calcium-containing liquor is heated to about 110-145.degree. C. with direct contact with the heating medium; a second stage wherein the liquor is maintained at this temperature in a retention tank for 1-20 minutes to reduce the amount of calcium in the liquor by precipitating calcium carbonate; and a third stage wherein the heat-treated liquor is evaporated for combustion.

Abstract: A method for improving purification efficiency when distilling off aldehyde contaminants during chemical manufacturing processes by adding a substituted aromatic amine having electron donating group substituents prior to the distillation column. The method is particularly useful for removal of aldehydes such as acrolein, generated as a by-product of acrylonitrile manufacture. Preferred aromatic amines are 2-amino aniline, 3,4-dimethyl aniline and 4-ethyl aniline.

Abstract: Inhibition of the formation of unsaturated carbon compounds during the heating of 141b involving the addition of various inhibitors such as butylene oxide and/or the use of a vessel made of a nickel alloy.

Abstract: A method of inhibiting fouling of one or more pieces of equipment for processing crude epichlorohydrin by treating at least one epichlorohydrin stream entering or exiting the one or more pieces of equipment with hydroquinone as an antifoulant.

Abstract: In a process for the purification by distillation of chlorinated aromatic hydrocarbons originating from the chlorination of aromatic hydrocarbons in the presence of FeCl.sub.3, the crude reaction product is first partially degassed and then directly subjected to distillation in the presence of said FeCl.sub.3.

Abstract: A process for preparing refined acrylic esters, the process including steps of distilling an acrylic ester containing stream in the presence of hydroquinone or substituted hydroquinone, at a concentration in the range of 200 to 5000 ppmw, wherein the distillation is carried out in the presence of 0.001 to 1.0 % v, on the vapor phase, of oxygen.

Abstract: A method of inhibiting the formation of fouling deposits occurring in spent caustic wash systems used for ethylene dichloride (EDC) manufacturing processes. Fouling occurs in these systems when they are in contact with EDC processing streams contaminated with oxygen-containing compounds, such as aldehydes. These deposits are formed in EDC processing streams contaminated with oxygen-containing compounds while in contact with a caustic solution having a pH>7. The invention comprises adding an effective deposit-inhibiting amount of a non-enolizable carbonyl compound to the caustic solution. Preferred non-enolizable carbonyl compounds are formaldehyde, glyoxal, benzaldehyde, p-anisaldehyde, formic acid, glyoxalic acid and paraformaldehyde.

Abstract: Methods and compositions for inhibiting fouling in vinyl monomers are disclosed. Alkylphosphonate esters or acids thereof are added to vinyl monomers, particularly ethylene dichloride, that are undergoing processing to inhibit fouling.

Abstract: An aqueous solution of free hydroxylamine is prepared by a process in which the solution obtained by treating a hydroxylammonium salt with a base is separated into an aqueous hydroxylamine solution and a salt fraction by treatment with water or steam at .ltoreq.80.degree.0 C. The novel process can be carried out in a simple and gentle manner and on a large industrial scale. Owing to the low thermal load, the low concentration of hydroxylamine and the short residence time in the process, the risk of decomposition is minimized.

Abstract: A method for the recovery of glycols from used antifreeze compositions by distillation entails the used antifreeze composition being treated before and/or during its distillation with an effective amount of sulfamic acid.

Abstract: Separation of 1,1-dichloro-1-fluoroethane (141b) from lower boiling components contained in a crude 141b feed stream mixture by adding the feed stream mixture, and, based upon the weight of 141b in the feed stream mixture, between 100 and 300 ppm of a component that will inhibit formation of 1,1-difluoro-1-chloroethane into a feed line of a distillation column operated at between 3 and 165 psig pressure with a temperature between 100.degree. F. and 250.degree. F. in the bottom reboiler section of the column.

Abstract: The invention relates to an improved distillation method wherein hexamethylcyclotrisiloxane is isolated from a crude blend thereof by mixing the crude blend with a hydrocarbon co-solvent having a normal boiling point of 125.degree. C. to 150.degree. C. and distilling the resulting mixture in an apparatus having a reboiler, a fractionating column and a condenser, whereby deposition of solid hexamethylcyclotrisiloxane in the condenser is eliminated.

Abstract: A polymerization inhibitor composition for inhibiting the polymerization of aromatic vinyl monomers at elevated temperatures comprising:(a) a benzofuroxan derivative of the formula ##STR1## wherein R is C.sub.1 -C.sub.4 alkyl or alkoxy; R.sup.1 is a nitro group; and m and n are each independently 0, 1, or 2; and(b) a solvent selected from the group consisting of toluene, xylene, ethylbenzene, vinyltoluene, divinylbenzene, alpha-methylstyrene, and a C.sub.12 -C.sub.18 hydrocarbon,and methods for inhibiting the polymerization of aromatic vinyl monomers at elevated temperatures using this composition.

Abstract: Inhibition of the formation of unsaturated carbon compounds during the heating of 141b by the use of a vessel pre-treated with HF to form an iron fluoride coating on the internal surfaces of said vessel.

Abstract: The polymerization of a vinyl aromatic monomer such as styrene is inhibited by the addition of a composition of a benzoquinone derivative and a hydroxylamine compound.

Abstract: The invention is a method of introducing an aggressive liquid additive into a vapor-containing process stream including (a) heating the liquid additive by a heating means thereby producing a heated additive; (b) passing the heated additive to an injection quill in fluid communication with the vapor-containing process stream; and (c) passing the heated additive from the injection quill into the vapor-containing process stream.

Abstract: A method of removing dimethyl terephthalate (DMT) from a vapor stream. The vapor stream includes dimethyl terephthalate (DMT), methylhydroxyethyl terephthalate (MHET), glycols and methanol. A distillation column is held under an elevated pressure of 100 to 500 kPag and at a temperature of at least 85.degree. C. It has (i) a plurality of distillation trays; (ii) methanol liquid sprays between the trays; (iii) a main spray zone below the trays and (iv) a liquid pool of methanol in the bottom of the column. The vapor stream is directed into the distillation column, above the liquid pool and below the main spray zone, thereby forming a stream of liquid and vapor. The stream of liquid is directed away from the distillation column walls and into the liquid pool at the bottom of the column.

Abstract: Inhibition of the formation of unsaturated carbon compounds during the heating of 141b involving the addition of various inhibitors such as butylene oxide and/or the use of a vessel made of a nickel alloy.

Abstract: An improved process for the heat-fractionation of a mixture comprising an organosilane and a borane or borane forming compound. The improvement comprises the presence of a tertiary organoamine or tertiary phosphorous compound at a concentration sufficient to reduce modification of the organosilane during the heat-fractionation process.

Abstract: Inhibition of the formation of unsaturated carbon compounds during the heating of 141b involving the addition of various inhibitors such as butylene oxide and/or the use of a vessel made of a nickel alloy.

Abstract: The present invention relates to a process for purifying fatty acid amides, which contains the following process steps:neutralization of the fatty acid by addition of an aqueous alkaline solution andsubsequent distillation of the neutralized mixture.

Abstract: A highly polymerizable dicyclopentadiene (DCPD) monomer composition is obtained. The dicyclopentadiene so obtained is highly suitable for ring-opening polymerization by metathesis catalysts. The active DCPD yields articles with excellent physical properties upon in-mold polymerization.

Abstract: The invention relates to a process for isolating pure diketene with recovery of materials of value by continuous, two-stage distillation of crude diketene at reduced pressure and with continuous reaction of the resulting distillation residue with acetic acid, pure diketene and acetic anhydride being separated off by means of the two-stage distillation. In the stabilization of the distillation residue with acetic acid, reutilizable acetic acid, which contains acetone with or without acetic anhydride, is recovered.

Abstract: A process for reducing the amount of unwanted di(meth)acrylate produced during the distillation of hydroxyalkyl acrylates or hydroxyalkyl methacrylates.

Abstract: A method for preventing fouling of ethylene dichloride distillation units which comprises treating the feed to such unit with a fouling preventing amount of a composition comprising (a) 2-15 weight % of an oil soluble polyacrylate ester or methacrylate ester with alcohol radical of the ester group containing from C.sub.4 -C.sub.22 carbon atoms which contains between 0.1-25 mole % of amino alcohol ester groups; (b) 20-40 weight % a phenylene diamine compound having the formula ##STR1## wherein R.sub.1, R.sub.2, R.sub.3, and R.sub.4 are the same or different and are hydrogen, C.sub.1 -C.sub.20 alkyl, C.sub.1 -C.sub.20 aryl, C.sub.1 -C.sub.20 alkaryl or C.sub.1 -C.sub.20 aralkyl, with the proviso that at least one of R.sub.1, R.sub.2, R.sub.3 or R.sub.4 is hydrogen; and (c) the balance is a heavy aromatic solvent.

Abstract: A distillation process for the separation of acetic anhydride from a mixture thereof with ethylidene diacetate wherein the mixture of acetic anhydride and ethylidene diacetate is fed to the mid section of a distillation column and a small amount of acetic acid is fed separately to the lower section of the column. The addition of the acetic acid suppresses tar formation during the distillation process.

Abstract: An improved process for separation of valuable components of a waste stream resulting from production of an olefin polymerization procatalyst by the addition to the waste stream of a separation solvent of intermediate boiling point, subjecting the resulting mixture to a first distillation zone to separate the desired waste stream components from the upper portion of the zone and passing the bottoms product to a second distillation zone wherein separation solvent is recovered from the upper portion of the zone for recycle and passing the bottoms product to disposal or further processing.

Abstract: A method for preventing fouling of ethylene dichloride distillation units which comprises treating the feed to such units with a fouling preventing amount of a composition comprising:______________________________________ INGREDIENTS WEIGHT % ______________________________________ a) An oil soluble polymethacrylate 2-15 ester which contains from between .1-25 mole % of amino alcohol ester groups with the balance of the alcohol radical of the ester group containing from C.sub.4 -C.sub.22 carbon atoms, b) a phenylene diamine compound 20-40 having the formula: ##STR1## wherein R.sub.1, R.sub.2, R.sub.3, and R.sub.4 are the same or different and are hydrogen, C.sub.1 -C.sub.20 alkyl, C.sub.1 -C.sub.20 aryl, C.sub.1 -C.sub.20 alkaryl or C.sub.1 -C.sub.20 aralkyl, with the proviso that at least one of R.sub.1, R.sub.2, R.sub.3 or R.sub.

Abstract: The process for rectification of phenol prepared from crude phenol being the product of decomposition of cumene hydroperoxide and having previously been distilled to remove large portions of acetone, cumene and alpha methylstyrene which includes:feeding the column overhead vapors to a condenser, thereby condensing a major portion of the overhead vapors;withdrawing a small portion of the overhead vapors from the condenser while still in a vapor state, the small portion being relatively enriched in lights and laden with light acids;returning the condensate from the condenser to the phenol distillation column as reflux; andwithdrawing product phenol from at least one-theoretical stage below the top of the phenol distillation column, the product phenol having improved clarity when dispersed in water, clarity being at least 93 percent light transmission as measured by an electrophotometer in a water light test.

Abstract: A method of inhibiting fouling in a crude ethylene dichloride stream comprises introducing into the stream an inhibiting amount of an antifoulant selected from (A) an acylated amine (e.g., reaction product of polyisobutylene and maleic anhydride) and a polyamine (B) magnesium alkyl aryl sulfonate, and (C) a mixture of A and B.

Abstract: The present invention provides a method for purifying alkanolamine solutions which have lost at least a portion of their acid gas sorption capacity due to degradation of the alkanolamine into heat stable salts. Particularly, it has been found that the alkanolamine solution may be rejuvenated by charging the solution to the feed zone of a distillation column reactor at temperatures above about 160.degree. C. and pressure of less than about 2000 mm Hg.

Abstract: The invention relates to a process for concentrating TBHP while avoiding flammability and explosion hazards by distilling a mixture of TBHP and TBA under reduced pressure of up to 300 mm Hg and separating a liquid TBHP concentrate containing at least 65 wt. % TBHP.

Abstract: A method is disclosed for enhancing the purification of citral by fractional distillation by inhibiting the formation of isocitrals from isomerization of citral during the distillation process. The method involves reducing the pH of a mixture containing citral to inhibit the formation of isocitrals from citral upon heating, such as in distillation. Lowering the pH below 7 reduces formation of isocitrals, but a pH of about 4 to 5 is especially preferred. Most preferably, this pH adjustment is accomplished by addition of an acid with a pKa between about 4 and 5.

Abstract: High boiling point aromatic free hydrocarbon liquids partially substituted for isophthalonitrile during its distillation fluidize the bottoms and increase isophthalonitrile yield.

Abstract: A process for preventing the substantial decomposition of an alkyl sulfide compound at high temperatures comprising combining a non-reactive basic compound with the alkyl sulfide compound prior to subjecting the resultant mixture to the high temperatures.

Abstract: A method for lightening a petroleum hydrocarbon oil by distillation in which 1 part by weight or less of an organic compound having an active mercapto group therein is added to 100 parts by weight of the petroleum hydrocarbon oil when the petroleum hydrocarbon oil is lightened by a thermal treatment.

Abstract: Aqueous solutions of free hydroxylamine are prepared by a process in which(a) hydroxylammonium sulfate is reacted with ammonia in a lower alkanol as solvent, and a solution of free hydroxylamine and solid ammonium sulfate with residues of hydroxylammonium sulfate is obtained,(b) solid ammonium sulfate and hydroxylammonium sulfate are separated off from the resulting reaction mixture, and an alcoholic solution of free hydroxylamine is obtained as the filtrate,(c) a stabilizer and water are added to the resulting alcoholic solution of free hydroxylamine, and(d) the alkanol is distilled off from the alcoholic solution containing free hydroxylamine, the stabilizer and water.

Abstract: This invention relates to a method for the purification of glycidyl acrylate or glycidyl methacrylate. Specifically, the invention effects the purification by using a residual catalyst-inactivating additive and consequently produces highly purified glycidyl acrylate or glycidyl methacrylate containing substantially no epichlorohydrin and having a low chlorine content.

Abstract: A process for decolorizing polyethylene polyamines using a chlorinated hydrocarbon. The discolored polyethylene polyamine and chlorinated hydrocarbon are contacted to form a decolorizing mixture, and the mixture is distilled. The decolored polyethylene polyamine is collected from the distillate.

Abstract: Deodorizing and/or physical refining of cocoa butter and cocoa butter substitutes is carried out in accordance with the principle of continuous counter-current falling film stripping steam distillation in at least two different zones, where different flow and current conditions prevail for the liquid film and the vapors, respectively. In the initial zone 10 the vapors pass through trickle passages having a hydraulic equivalent diameter greater than the hydraulic equivalent diameter in the final zone 22.The working pressure in the top of the falling film column 10 is maintained below 2.0 mbar, and in the bottom of the falling film column 22 it is maintained by at most 1.6 mbar in excess of that in the falling film column 10. The accumulation of any significant liquid content in the bottoms of the serially operating zones is avoided. Stripping steam is supplied in an amount of 2 to 10 kg of steam per 100 kg of charged liquid.

Abstract: The deodorization and/or physical refining of high-boiling organic edible oils, fats and esters is carried out according to the principle of continuous counter-current falling film stripping steam distillation in an internally imposed temperature field in at least two different zones having different flow conditions for the liquid film and the vapors, respectively, prevailing therein. In the initial zone 10 directly adjacent the liquid charge and ensuring at least two separation stages the vapors flow through trickle passages having a hydraulic equivalent diameter of 73 to 150 mm. If necessary, this initial zone may be subdivided, wherein in the first sub-zone the trickle passages are provided with hydraulic equivalent diameters of 120 to 150 mm and in the second sub-zone the trickle passages are provided with hydraulic equivalent diameters of 73 to 120 mm.

Abstract: A method for recovery of extraction solvent from a dissolved solute wherein halogen gas evolution and halogen compound retention in the solute are minimized comprises heating a solution of a halogenated organic solvent and the extracted solute in the presence of an ammonium, Group I metal or Group II metal salt of an acid of carbon number 1 to 6, such as ammonium bicarbonate, ammonium carbonate, ammonium formate, sodium carbonate, sodium formate, or calcium formate, to recover the solvent and the solute.

Abstract: The concentration buildup of contaminants methylacetylene and propadiene in a propylene/propane fractionation column is prevented by controlling the injection of propane from a source external from the feedstream into the inlet stream to the column in response to the measured propane content of the feedstream downstream of the point of propane injection, the measured methylacetylene content of the bottoms product from the column, or the measured methylacetylene content of a sample from a tray of the column.

Abstract: The subject invention relates to the preparation of storage-stable alkylene glycol monoalkyl ethers having the general formulaR--(O--A--).sub.n OHin which A represents an ethylene or propylene group, R denotes a C.sub.1 -C.sub.4 -alkyl group, and n has a value of 1 to 4. They are prepared by carrying out the fractional distillation of a mixture which is produced by the alkali catalyzed reaction of ethylene oxide or propylene oxide with an alcohol in the presence of 0.1 to 20 ppm of ammonia based on the amount of the mixture.

Abstract: A method for the separation of indole by distilling an indole-containing reaction fluid obtained by the reaction of aniline with ethylene glycol or by the reaction of N-(.beta.-hydroxyethyl)aniline, which comprises bringing the reaction fluid into contact with a basic substance prior to and/or during the distillation. This method can prevent the deterioration of indole during the distillation procedure.