Abstract: The separation of acrylic acid from a mixture of acrylic acid and acetic acid found in the reaction product stream obtained in the process of producing acrylic acid by the oxidation of propylene or acrolein is improved by removing a vapor sidestream from the solvent recovery column found in the process. Acetic acid is then separated from this stream without the addition of external heat.

Abstract: In the recovery and purification of acrylonitrile or methacrylonitrile obtained by the ammoxidation reaction of propylene or isobutylene, the bottoms stream associated with the column for extractively distilling acrylonitrile or methacrylonitrile is both reduced in size and increased in polymer concentration by removing a vapor stream containing water from the lower fourth of said column, thus reducing the amount of solids-containing waste streams to be treated.

Abstract: Disclosed is a process for separating 11-cyanoundecanoic acid, cyclohexanone and .epsilon.-caprolactam from a pyrolysis product obtained by pyrolyzing 1,1'-peroxydicyclohexylamine in the presence of steam at a temperature of 300.degree. to 1,000.degree. C. The pyrolysis product is first contacted with a mixture comprised of aqueous ammonia and at least one organic solvent selected from benzene, toluene and xylene, and the so prepared liquid is separated into the oily layer and the aqueous layer. On one hand, the oily layer is distilled to separate cyclohexanone therefrom. On the other hand, the aqueous layer is acidified to a pH of below 4.0 by adding thereto a mineral acid and maintained at a temperature of 40.degree. to 100.degree. C. to separate crude 11-cyanoundecanoic acid in molten form from the aqueous layer, and then, the separated crude molten 11-cyanoundecanoic acid is washed with hot water to extract .epsilon.-caprolactam therefrom.

Abstract: There is disclosed an azeotropic distillation process for separating toluene from methyl isobutyl ketone (MIBK) in a spent liquor mixture. A toluene azeotrope former, preferably methanol, is added to the liquor in an amount sufficient to form an azeotrope with all of the toluene present in the mixture. The methanol is added in an amount of at least about 2.62, typically an excess amount of about 3.4 to about 6.3 parts by weight of methanol per 1.0 part by weight of toluene. The resulting azeotrope of methanol and toluene is then separated by distillation from the MIBK. The methanol may be subsequently recovered from the toluene by extraction with water. Other toluene azeotrope formers may be utilized.

Abstract: An improved process for recovering isobutylene contained in a mixture of hydrocarbons having four carbon atoms by selective extraction with an aqueous solution of sulfuric acid of a concentration of about 50 wt. % followed by separating the isobutylene-rich sulfuric acid extract by a first flash distillation of the extract and by a second physical separation of the isobutylene-enriched extract from said flashing step (which the latter physical separation is preferaby a second flash distillation at a temperature which is higher than the first and is at 75.degree. C. or less, and wherein said first flash distillation is between 10.degree. and 60.degree. C. and both distillations are preferably at a pressure between 0.5 and 1.5 bars absolute to give an isobutylene purity greater than 99.5%).

Abstract: A process for concentrating at least one of (a) individual halogenoanthraquinones (b) binary mixtures of di-halogenoanthraquinones and (c) binary mixtures of trihalogenoanthraquinones, from a mixture containing at least two halogenoanthraquinones, comprising subjecting said mixture containing at least two halogenoanthraquinones to fractional vacuum distillation in a heated rectification column having an efficiency corresponding to about 20 to 50 theoretical stages with an absolute pressure at the top of about 0.5 to 50 mm Hg and a reflux to take-off ratio of about 5/1 to 50/1.

Abstract: A method and apparatus for removing organic contaminants from an aqueous metal-cleaning solution. The apparatus includes a first conduit, or pipe, for removing portions of the contaminated aqueous solution from its tank. The solution enters an extractor which permits intimate contact between the contaminated solution and an organic solvent. A second tube, or conduit, returns the aqueous solution, purified by this contact, to the original tank. A third conduit removes the organic solvent from the extractor after its contact with the aqueous solution, by which time it will contain organic components from the aqueous solution. This solvent, with the contaminants, enters a separator, such as a still, which removes the contaminants from it. The purified organic solvent then returns to the extractor along a fourth conduit. The cleansing operation proceeds intermittently or, preferably, continuously.

Abstract: Dimethyl carbonate is obtained pure, from its solutions in methanol, by extractive distillation carried out with a temperature of from 60.degree. C. at the top to 250.degree. C. at the bottom of the column and employing, as the extractant, an aprotic organic liquid which is substantially inert toward dimethyl carbonate, boils at above 100.degree. C. at standard pressure, is miscible with dimethyl carbonate in all proportions and has a dielectric constant .epsilon. of from 4 to 90 and a dipole moment .mu. of from 1.5 to 5 Debye.

Abstract: A process for separating, by means of a selective solvent, a mixture of C.sub.

Abstract: Carbon tetrachloride and chloroform are separated as a light fraction from ethylene dichloride by distilling the ethylene dichloride under reflux conditions to maintain a chloroform concentration greater than 51.5 mole percent in the reflux liquid.

Abstract: A method for separating two liquid components from a mixture by distilling the mixture in the presence of a third liquid which is immiscible at least with the component having the higher boiling point with the third liquid having a boiling range from at least the boiling point of the lower boiling component up to the boiling point of the higher boiling component. In a preferred embodiment the liquid mixture components are glycol and water and the third liquid is a naphtha fraction having a boiling range from about 212.degree. F. (100.degree. C.) to about 410.degree. F. (210.degree. C.).

Abstract: A unique combination of specially chosen entrainers, e.g., pentanes and cyclohexane, and high-pressure azeotropic distillation conditions, e.g., 100-200 psig., provides an economically efficient separation of a C.sub.2 -C.sub.5 alkyl alcohol, e.g., isopropanol, from its aqueous mixture; and also results in the production of a useable steam having a sufficient pressure, e.g., from 10 psig. to 30 psig. Preferably, said azeotropic distillation is conducted in the substantial absence of oxygen, e.g., less than 1 wppm.

Abstract: A continuous-operation extractor for the solvent extraction of low-molecular weight compounds for a solid, e.g. granular polyamide, comprises an upright housing formed internally with vertically extending pipes beneath each of which a steam nozzle opens. Deflectors are provided above the upper ends of each pipe and an overflow conducts the solids downwardly from one extractor stage to the next. A solid inlet communicates with the uppermost extraction stage and is provided with inclined perforated baffles while below the lowermost stage a float-controlled valve regulates the steam inlet.

Abstract: Process for isolating propylene glycol diacarboxylates in the preparation of propylene oxide by reaction of propylene with a solution of percarboxylic acid in an organic solvent, the boiling point of which is lower than that of the carboxylic acid which corresponds to the percarboxylic acid used as the epoxidizing agent, and higher than that of propylene oxide, separation, by distillation, of the reaction mixture which essentially contains propylene oxide, the carboxylic acid corresponding to the percarboxylic acid used as the epoxidizing agent and one or more of the by-products propyleneglycol, propylene glycol monocarboxylate and propylene glycol dicarboxylate as well as propylene and the organic solvent, into a fraction containing propylene oxide and propylene and a fraction containing the carboxylic acid, the by-products mentioned and the organic solvent and further separation of the fractions into the individual components by distillation.

Abstract: A direct contact condenser of a distillation system has a condenser vessel comprising a vapor space with a vapor inlet, a condensate pump, with the liquids' level defining the top of the sump and the bottom of the vapor space. The thermal efficiency of the system is improved wherein the heat of condensation is concentrated in one of two coolant effluent lines while the other coolant line removes unheated excess liquid coolant. This is accomplished with the use of two temperature sensors at spaced vertical locations of the sump and a liquid level control together regulating the opening and closing of respective valves in respective influent and effluent lines of the sump.

Abstract: An apparatus for the solar distillation of contaminated water which includes a substantially airtight enclosure having an evaporation chamber and condensation chamber. The evaporation chamber has a lower reservoir and an upper inclined surface which is transparent to solar radiation. The condensation chamber includes a thermally conductive condensation wall and a collecting reservoir for collecting the condensed water. A thermal insulative partition is located intermediate the evaporation chamber and the condensation chamber, and includes an upper port and a lower port. At least one thermally conductive conduit may be located within the condensation chamber and externally vented at the upper and lower portions thereof.

Abstract: Crude phenol is recovered from CHP reaction products by continuously feeding to a main column separating in its uppermost section phenol from crude acetone, this fraction being removed overhead, and in the lower section crude phenol from higher boilers, including acetophenone and carbinol, the crude phenol being removed as a sidestream fraction from the main column at a point in the column above the feed-point wherein the total concentration of acetophenone plus carbinol is less than 1,000 ppm and the higher boiling compounds being removed as a base fraction.

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: The formaldehyde hydrazone of UDMH can be removed from an aqueous solution f UDMH by codistillation with a hydrocarbon or other solvent which is inert to both acidic or basis mediums. The solvent can then be recovered from the hydrazone solution by washing with an acid solution and the solvent can be reused.

Abstract: A process for recovering alkoxyketone compounds from mixtures of the alkoxyketone compound and the corresponding 1-alkoxy-2-alkanol compound by extractive distillation with diols, triols and polyols as extractants.