Abstract: The level of aldehyde and ketone impurities in tetrahydrofuran can be significantly reduced by bringing the tetrahydrofuran into contact with sodium borohydride and then separating the modified impurities and the tetrahydrofuran.

Abstract: Solvents which may be used as mediums for the polymerization of olefinic hydrocarbons to form polymers useful as membranes in a gas separation process require purification to remove any impurities which will effect the aforesaid polymerization. Purification of these solvents such as cyclohexane may be effected by treating the solvent with titanium tetrachloride, contacting the solution with an adsorbent such as silica gel and thereafter distilling the solvent in the presence of a purification agent such as an alkaline metal aluminum hydride or borohydride.

Abstract: An improved process for recovering high purity resorcinol produced by the rearrangement of m-diisopropylbenzene dihydroperoxide in which the rearranged product mixture is neutralized, the neutralized mixture being filtered, the filtrate being admixed with toluene, the acetone being removed by distillation and the acetone-free rearranged product/toluene mixture being steam distilled to provide an aqueous resorcinol containing phase from which the resorcinol is recovered.

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.

Abstract: In the purification of thionyl chloride by addition of sulphur and distillation in the presence of a catalyst, the improvement which comprises effecting the distillation in the presence of an aluminum compound as the catalyst. Advantageously the aluminum compound is aluminum chloride, the sulphur is added in about 2.5 to 7% by weight based on thionyl chloride, the aluminum chloride is in admixture with sulphur monochloride in about 0.01 to 5% by weight calculated as aluminum and based on thionyl chloride, and prior to distillation the mixture of crude thionyl chloride, sulphur and aluminum chloride is heated to between about 50.degree. and 60.degree. C. for about 10 to 60 minutes. The resulting thionyl chloride is of extremely high purity.

Abstract: A method of separating acids or bases from vapors which are conveyed along with distillation vapors during concentration of a solution, comprising, passing said distillation vapors containing an acid or base, while being maintained at their existing pressure and temperature, through a salt solution which boils at said temperature and pressure, wherein, if an acid is to be removed from the distillation vapors, the salt solution contains a salt having an anion corresponding to that of the acid while being supplied with a base in an amount required to neutralize the acid, the cation of the base proportion corresponding to that of the salt, while, if a base is to be removed from the distillation vapors, the salt solution contains a salt having a cation corresponding to that of the base while being supplied with an acid in an amount required to neutralize the base in the distillation vapors, the anion of the acid corresponding to that of the salt so that salts are formed during neutralization which correspond to t

Abstract: A new and improved contact lens is provided and is made by a process which uses a distillation step with an addition of a carbon decolorizing agent to the solution being distilled. The carbon decolorizing agent prevents curdling and removes impurities in the distillation step. The result is a contact lens with a very high water content and with good oxygen permeability characteristics.

Abstract: Halogenated hydrocarbon and uncontaminated water is recovered from a stream of process water contaminated with halogenated hydrocarbon and hydrogen halide. The process water is neutralized and then distilled to obtain a first fraction containing halogenated hydrocarbon and water and a second fraction containing uncontaminated water. The first fraction is allowed to settle into layers of halogenated hydrocarbon and water which are then removed.The contaminated stream may be obtained from a process for the solvent dewaxing of a petroleum fraction.

Abstract: Fluoride ions are removed from nitric acid solution by contacting the vaporized solution with alumina or zirconium.

Abstract: A process for the purification of crude thionyl chloride wherein the crude thionyl chloride is distilled in the presence of sulfur and a sulfur-aluminum chloride catalyst to convert the impurities, sulfuryl chloride and sulfur dichloride and remove them from the distillate of thionyl chloride. The thionyl chloride collected will contain less than 0.01% sulfuryl chloride, less than 0.1% sulfur monochloride and less than 0.01% sulfur dichloride.

Abstract: Crude liquid polyether-polyols containing an alkaline catalyst are purified by the steps of:neutralizing said crude liquid polyether-polyol with a mineral acid having a dissociation constant of greater than 10.sup.-3 at 25.degree. C.distilling off water from said liquid, and filtering the same. The improvement resides in the step of adding a hydrate of a metal salt of said mineral acid to the liquid polyether-polyol at a stage before the distillation step for promoting the crystal growth of a salt formed from said alkaline catalyst by the neutralization.

Abstract: A process has been developed for isolating aromatic dinitro compounds by using nitric acid in specified concentrations in different portions of a rectifying column and separating off the mixture of aromatic dinitro compounds from the sump of the rectifying column.

Abstract: The invention relates to a process for purifying 1,2-dichloroethane which is recovered during incomplete thermal cracking to vinyl chloride and contains contaminants boiling at a temperature lower than 83.7.degree. C. under a pressure of 1011 millibars, briefly termed low boilers, and contaminants boiling at a temperature higher than 83.7.degree. C. under a pressure of 1011 millibars, briefly termed high boilers. More particularly, low boilers are distilled off overhead from contaminated 1,2-dichloroethane, in a first distilling zone; a portion of low boiler concentrate is continuously treated at 30.degree. to 85.degree. C.

Abstract: A method for conducting chemical reactions and fractionation of the reaction mixture comprising feeding reactants to a distillation column reactor into a feed zone and concurrently contracting the reactants with a fixed bed catalytic packing to concurrently carry out the reaction and fractionate the reaction mixture.For example, a method for preparing methyl tertiary butyl ether in high purity from a mixed feed stream of isobutene and normal butene comprising feeding the mixed feed stream to a distillation column reactor into a feed zone at the lower end of a distillation reaction zone, and methanol into the upper end of said distillation reaction zone, which is packed with a properly supported cationic ion exchange resin, contacting the C.sub.4 feed and methanol with the catalytic distillation packing to react methanol and isobutene, and concurrently fractionating the ether from the column below the catalytic zone and removing normal butene overhead above the catalytic zone.

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, wherein said mixtures contain an organic or inorganic base.

Abstract: Heavy petroliferous stocks such as vacuum and atmospheric resids, tar sand oils, shale oils, liquids from conversion of coal and the like are concurrently distilled and hydroprocessed for removal of sulfur, nitrogen and metals and are hydrocracked or otherwise hydroprocessed in a packed distillation column under hydrogen pressure wherein the packing is constituted, at least to a substantial extent in both stripping and rectifying sections by catalyst suited to the desired conversions. In a specific application to catalytic hydrodewaxing of lubricating oil stocks, improvement of Viscosity Index (VI) of dewaxed product results.

Abstract: An aromatic acyl chloride is obtained with industrial advantages by reacting an aromatic carboxylic acid, phosphorus trichloride and chlorine, treating the reaction mixture comprising by-produced phosphorus pentachloride with at least one treating agent selected from water and phosphorus compounds to convert the phosphorus pentachloride into phosphorus oxychloride, and then subjecting the resulting reaction mixture to distillation to obtain the desired aromatic acyl chloride.

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: Butadiene is recovered from a hydrocarbon fraction containing it together with butenes and acetylene hydrocarbons by introducing said fraction into a first extractive distillation column, feeding aqueous acetonitrile into said column above the introduction point of said fraction and extracting a vapor stream containing butadiene below said introduction point; feeding said vapor stream into a second extractive distillation column, feeding aqueous acetonitrile above the introduction point of said vapor stream and recovering a vapor stream consisting essentially of butadiene at the top of said second column; and rectifying this last vapor stream to recover pure butadiene.

Abstract: The present invention refers to a process for the purification of acetonitrile from crude acetonitrile or mixtures containing the same, which comprises the following operations:(a) transformation of hydrogen cyanide and acrylonitrile into compounds of higher molecular weight,(b) removal of most of the water in an azeotropic distillation column, and(c) separation of acetonitrile from the compounds of higher molecular weight and residual water in rectifying columns.

Abstract: Recovery of the chemical components of a cellulosic organic solvent regenerating solution containing a dialkylacylamide, a lower aliphatic monohydric alcohol, a nitrite of the alcohol and nitric acid. The process comprises distilling the solution to remove the alcohol nitrite and alcohol, leaving the dialkylacylamide and nitric acid, recovering the alcohol, hydrolyzing to convert the alcohol nitrite to the alcohol and nitrous acid, neutralizing the nitric and nitrous acid with an alkali or alkaline earth metal oxide or hydroxide and distilling the solution to remove water and to separate and recover the remaining alcohol, the dialkylacylamide and the nitrate and nitrite salts. The nitrite and nitrate salts are converted by pyrolysis to nitrogen dioxide. The process results in substantially total recovery of the process chemicals.

Abstract: A method for the purification of monochlorobenzene contaminated with partly chlorinated aliphatic compounds comprises (a) selectively photochlorinating the contaminated monochlorobenzene to convert the partly chlorinated aliphatic compounds to substantially fully chlorinated aliphatic compounds and (b) separating the monochlorobenzene from the more fully chlorinated aliphatic compounds by distillation.

Abstract: A method for separating niobium pentachloride and tantalum pentachloride contaminants from crude titanium chloride vehicle by addition of water to said vehicle to form substantially selectively solid hydration products of such contaminants which are readily separable.

Abstract: Process is provided for removal of chloroprenes as impurities from ethylene dichloride streams formed in the production of vinyl chloride by the thermal cracking of ethylene dichloride. The ethylene dichloride stream is subjected to distillation in a distillation zone to which free chlorine gas is introduced, thereby chlorinating the chloroprenes contained therein and forming higher boiling chlorocarbons as reaction products. The higher boiling chlorocarbons, together with ethylene dichloride, may be removed as bottoms and passed to a second distillation zone for separation of ethylene dichloride from the higher boiling impurities, thereby producing a substantially pure ethylene dichloride which may be recycled to the cracking step.

Abstract: A process for separating mixtures of close boiling alkenes and alkanes which employs catalytic dealkylation of alkylphenols.

Abstract: A process for the production of paraxylene by the catalytic isomerization of xylenes wherein the reaction zone effluent is fractionated in three columns in series with the overhead product of the second column in the series being sent to a paraxylene separation zone, C.sub.9 hydrocarbons being rejected as the bottoms product of the third column, and the overhead product of the third column being combined with the raffinate stream of the paraxylene separation zone and recycled to the isomerization zone.

Abstract: Styrene is inhibited against polymerization during the distillation thereof by incorporating therein, in an amount sufficient to inhibit polymerization thereof, the dinitrophenol solution recovered from styrene still residues or tars resulting from the distillation of styrene in the presence of dinitrophenol. The recovered dinitrophenol solution is a more effective polymerization inhibitor than dinitrophenol per se.

Abstract: Crude ethylene oxide present in the dilute aqueous solution resulting from the extraction with an aqueous solvent of ethylene oxide from the gaseous stream obtained by catalytic oxidation of ethylene is purified by desorption, liquefaction, distillation in a fractionating column and final desorption treatment to remove absorbed non-condensable gases. The fractionating column is heated by condensation of the water vapor evolved during desorption and a liquid stream of ethylene oxide rich in acetaldehyde is discharged from the bottom, treated to convert a fraction of said acetaldehyde into high-boiling products, distilled to remove the latter as bottoms and returned to the fractionating column.

Abstract: 1,4-NAPHTHOQUINONE IS REMOVED FROM PHTHALIC ANHYDRIDE BY HEATING WITH ELEMENTARY SULFUR AT TEMPERATURES IN THE RANGE OF FROM 200.degree. TO 300.degree. C.

Abstract: A mixture of cresylic acids containing a substantial amount of 2,6-xylenol is contacted with an ester-forming phosphorus compound in an amount in the range of 0.5 to 5.0 equivalents per equivalent of cresylic acids other than 2,6-xylenol. The temperature is in the range of 50.degree.-250.degree. C., and a catalyst may or may not be employed. Under these conditions, aryl phosphates are formed more rapidly from the cresylic acids other than the 2,6-xylenol. The substantially unreacted 2,6-xylenol is readily separated from the aryl phosphates.

Abstract: A process for separating lower-boiling chlorohydrocarbons and water from neutralized crude chlorohydrocarbons having at least two carbon atoms, which comprises fractionally distilling the crude chlorohydrocarbons in a fractionating column, thereby obtaining a fraction A containing the desired product which is withdrawn at the bottom of the column practically free of impurities, and a fraction B, comprising water, impurities having a lower boiling point, and entrained amounts of the desired chlorohydrocarbon, withdrawing said fraction B from the top of the column and, while still in gaseous state, neutralizing fraction B with an aqueous solution of a mixture of basic compounds, thereby avoiding corrosion of the apparatus, and thereafter subjecting the gaseous fraction to stepwise condensation with recovery of the entrained portions of said chlorohydrocarbon by returning them to the fractionating column, while separately removing water and undesirable impurities.