Abstract: An apparatus for the purification of crude N,N′-diphenyl-p-phenylenediamine (DPPD) in which there is an extraction unit containing a liquid permeable container and an adsorption layer downstream of the container, a solvent evaporator downstream of the adsorption layer, a filter unit, a line for returning the filtrate to the solvent evaporator, and a condenser for returning solvent to the extraction unit.

Abstract: A process for purifying alkenyl compounds having a divalent or trivalent heteroatom in the &agr;-position relative to the double bond by distillation comprises carrying out at least two distillations in which the purified alkenyl compounds are obtained from the gas phase by condensation, where the time between the first distillation after the synthesis of the alkenyl compounds and at least one further distillation is at least one day and the purified alkenyl compounds have an APHA color number of <30.

Abstract: A mixture of materials having different boiling points is separated into fractions having different boiling points. The separated fraction containing the desired product is stripped using the vapors of a lower boiling fraction. The process of the present invention is particularly useful for recovering a desired isomer or isomer mixture from a technical mixture obtained during production of an aromatic amine such as toluenediamine. Little or no unwanted isomer or by-product is present in the isomer or isomer mixture product of this process.

Abstract: An improved synthesis of N,N,-disubstituted-p-phenylene-diamine (DSPDA) preferably di-n-butyl-p-phenylenediamine is disclosed. The improvement rests on the discovery that DSPDA and its salts are extremely sensitive to oxygen so that once the product DSPDA or its salt is formed, oxygen must be excluded from all manipulations.

Abstract: The present invention provides novel processes for the preparation of Form A of fluoxetine hydrochloride.

Abstract: The present invention provides novel amorphous fluoxetine hydrochloride as a useful intermediate for the preparation of Form A of fluoxetine hydrochloride.

Abstract: A method is disclosed for the preparation of very small particle size, relatively pure 1,3,5-triamino-2,4,6-trinitrobenzene (TATB). Particles of TATB prepared according to the disclosed method are of submicron size and have a surface area in the range from about 3.8 to 27 square meters per gram.

Abstract: The present invention provides novel processes for the preparation of Form A of fluoxetine hydrochloride.

Abstract: A process for separating 2-aminomethylcyclopentylamine from a mixture consisting of hexamethylenediamine and 2-aminomethylcyclopentylamine by distilling the mixture at a pressure from 1 to 300 mbar.

Abstract: A process for distillative separation of part or all of an imine (III) from a mixture (II) comprising an amine (I) and said imine (III) comprises adding to the distillation mixture a compound (IV) which is inert toward said amine (I) under distillation conditions and whose boiling point is above the boiling point of said amine (I) under said distillation conditions to obtain, after the distillation, a mixture (VI) comprising essentially said compound (IV).

Abstract: The subject of the present invention is a process for the decoloration of aqueous effluents comprising aromatic amines or their derivatives, in which process the effluents are brought into contact with at least one agent chosen from alkali metal or alkaline earth metal sulfites or alkali metal or alkaline earth metal hydrogensulfites.

Abstract: The invention concerns a method for displacing, at least partially, an aniline from its chlorhydrate, characterized in that said aniline is selected among anilines whereof the conjugate acid has a pKa not more than 6 and in that it consists in a step wherein it is subjected at a temperature not less than 50° C., advantageously about 70° C. to a reaction medium containing said chlorhydrate at least partially dissolved in a weakly polar solvent. The invention is applicable to organic synthesis.

Abstract: A method is disclosed for the preparation of very small particle size, relatively pure 1,3,5-triamino-2,4,6-trinitrobenzene (TATB). Particles of TATB prepared according to the disclosed method are of submicron size and have a surface area in the range from about 3.8 to 27 square meters per gram.

Abstract: The invention relates to a process for treating fruit and vegetables after harvesting, using, as plant-protection treatment composition, the mixture with water of the reaction medium resulting from the implementation of steps of purification of a plant-protection product contaminated with impurities of aromatic primary amine type. The process contains the steps of: a) the placing in contact with stirring, at a temperature between 15 and 25° C., of an aqueous solution of an alkali metal nitrite with an organic solution prepared by dissolving the said plant-protection product to be purified in a solvent chosen from a nonionic surfactant, a C2-C12 glycol and mixtures thereof; b) the addition of a strong inorganic acid to the resulting reaction medium, while stirring at the said temperature; c) followed by heating of the reaction medium to a temperature of between 30 and 70° C.

Abstract: The invention concerns a method for preparing an optically active alcohol of formula (I) in which the carbon atom indicated by the symbol * can have the configuration (R) or (S) and X represents a non-substituted amino group or a mono- or di-(C.sub.1 -C.sub.4)alkylamino group optionally salified from corresponding ketones by catalytic hydrogenation in the presence of a rhodium complex.

Abstract: A simple and inexpensive process is described for reducing the concentration of N-nitroso-containing compounds in compositions comprising N-nitroso-containing compounds and other desired compounds wherein the N-nitroso-containing compounds thermally decompose at a temperature below the decomposition temperature of the desired compounds. For compositions comprising dinitroaniline herbicides wherein the N-nitroso compound is a N-nitroso derivative of a precursor in the manufacture of the herbicide, for example Flumetralin, N-ethyl-N-(2-chloro-6-fluorobenzyl)-2,6-dinitro-4-trifluoromethylaniline, the process requires heating the mixture to a temperature greater than about 120.degree. C., and holding the composition at that temperature for a time effective to decompose the N-nitroso compound present in the mixture. Volatile decomposition products are advantageously removed from the composition.

Abstract: A process is provided for removing primary amines from an amine-containing stream. Particularly, a process is provided for removing primary amines from said amine-containing stream by reacting said primary amine with a dione. More particularly, a process is provided for removing n-amylamine from an amine-containing stream comprising piperidine by reacting n-amylamine with 2,5-hexanedione.

Abstract: A process for purifying 1,3-bis(aminophenoxy benzene) (APB) on a manufacturing scale to at least 99.5% purity comprises the sequential steps of (a) forming the dihydrochloride salt of APB (hereinafter APB-HCl), (b) recrystallizing the APB-HCl from isopropyl alcohol, and (c) converting the APB-HCl to free APB.

Abstract: This invention relates to stable aromatic amine compositions. These compositions comprise a) a compound selected from the group consisting of alkali metal salts of sulfur compounds, hydrates thereof and aldehydes thereof, aluminum hydrides, borates and boron compounds; and b) an aromatic amine. This invention also relates to a process for stabilizing the color of aromatic amines, and to the production of polyether polyols from these stable aromatic amine compositions.

Abstract: A method for the purification of dinitroanilines having herbicidal activity by means of the known reactions of denitrosation using acid, and denitration in a neutral or basic environment in the presence of a phase-transfer catalyst, wherein:the denitrosation reaction is effected on the dinitration mixture containing the dinitroaniline of interest and the corresponding unwanted N-nitroso- and N-dinitroaniline impurities, and in the absence of solvent,the denitration reaction is conducted sequentially to the denitrosation reaction in the same reactor with the addition to the denitrosation product as such of an aqueous base, and of the said phase-transfer catalyst.

Abstract: A process for the stabilizing of an organosilane with an effective, stabilizing amount of purified N,N'-diphenyl-p-phenylenediamine (DPPD). The purification of crude DPPD involves extracting crude DPPD with hexane thereby forming an extract solution containing DPPD, passing the extract solution over an adsorption layer comprising silica gel as the adsorbent to form a solution containing purified DPPD and recovering the purified DPPD from the solution.

Abstract: A simple and inexpensive process is described for reducing the concentration of N-nitroso-containing compounds. The process is applicable for compositions comprising N-nitroso-containing compounds and other desired compounds wherein the N-nitroso-containing compounds thermally decompose at a temperature below the decomposition temperature of the desired compounds. For compositions comprising N-nitroso-pendimethalin in Pendimethalin, the process requires heating the mixture to a temperature greater than about 120.degree. C., and holding the Pendimethalin at that temperature for a time effective to decompose the N-nitroso-pendimethalin present in the mixture. Volatile decomposition products are advantageously removed from the composition.

Abstract: A process and apparatus for the removal of aromatic amines from soil and water is described. In particular, treatment trains are described in which soil washing or low temperature desorption process effect removal of contaminant, such as xylidines from soil and steam stripping is utilized to remove contaminant from water. Further treatment through organic acid precipitation and advanced oxidation produce clean water and precipitated salts which may be recovered.

Abstract: Existing coloration of a liquid ring-polyalkyl-substituted aromatic primary diamine is reduced by blending into such diamine a color-reducing amount of at least one dihydrocarbylhydroxylamine. Preferably, the resultant product is stored in a closed container under an inert atmosphere.

Abstract: The invention provides a process for the separation of (RR,SS) 2-dimethylaminomethyl-1-(3-methoxyphenyl) cyclohexanol hydrochloride ?(RR,SS)-Tramadol!, from a mixture consisting of (RR,SS) Tramadol and (RS,SR)-2-dimethylaminomethyl-1-(3-methoxyphenyl) cyclohexanol ?(RS,SR)-Tramadol!, which process includes combining the mixture with an electrophilic reagent, the reagent selectively reacting with the hydroxyl group of (RS,SR)-Tramadol, leaving most of the (RR,SS) Tramadol intact, and precipitating the remaining, practically pure (RR,SS) Tramadol from the mixture.

Abstract: Odor formation during storage of (hydrocarbylthio)aromatic amines due to formation and release of odoriferous sulfur-containing species such as dihydrocarbyldisulfides, is suppressed. To accomplish this, a small amount of N,N-dihydrocarbylhydroxylamine odor-inhibitor (e.g., N,N-diethylhydroxylamine) is blended with the (hydrocarbylthio)aromatic amine. This enables products such as a mixture of 3,5-di(methylthio)-2,4-diaminotoluene and 3,5-di(methylthio)-2,6-diaminotoluene) to be stored for long periods of time with significantly reduced formation and release of odoriferous sulfur-containing species.

Abstract: A process for the purification of crude N,N'-diphenyl-p-phenylenediamine (DPPD), which comprises extracting crude DPPD with a hydrocarbon or hydrocarbon mixtures thereby forming an extract solution containing DPPD, passing the extract solution over an adsorption layer, and recovering purified DPPD from the solution.

Abstract: A process is provided for preparing 2,6-dinitro-N,N-dipropyl-4-(trifluoromethyl)benzenamine from 4-chlorotrifluoromethylbenzene. The process includes a two stage nitration and an amination step. Ethylene dichloride is utilized as a diluent and solvent in the nitration steps. Spent acid from the first nitration is reconstituted with sulfur trioxide for use in the second nitration. Spent acid from the second nitration is used directly in the first nitration and evaporation is used to remove nitrosoamines from the final trifluralin product.

Abstract: The invention relates to a process for the fractionation and purification of aromatic polyamine mixtures and to the use thereof.

Abstract: The invention relates to a process for the fractionation and purification of aromatic polyamine mixtures and the use thereof.

Abstract: The invention relates to a process for the fractionation and purification of aromatic polyamine mixtures and their use.

Abstract: The present invention concerns a process for producing crystals of 3-amino-2-hydroxyacetophenone salt having a high bulk density and improved flow properties, by treating 3-amino-2-hydroxyacetophenone of formula (1) ##STR1## or hydrogen halide salt thereof with sulfuric acid, in a solvent.

Abstract: The invention relates to a process for the fractionation and purification of aromatic polyamine mixtures and to their use.

Abstract: The invention provides a process for the purification and isolation of (RR,SS)-2-dimethylaminomethyl-1-(3-methoxyphenyl)cyclohexanol from mixtures also containing the (RS,SR) isomer comprising reacting the above mixture in a solvent at elevated temperature under acidic conditions, whereby the (RS,SR) isomer is selectively converted to the (RR,SS) isomer, 1-(3-methoxyphenyl)-2-dimethylaminomethylcyclohex-6-ene, 1-(3-methoxyphenyl)-2-dimethyl-aminomethylcyclohex-1-ene or a mixture thereof, selectively precipitating the desired (RR,SS) isomer as an amine acid salt, and recrystallizing the purified product.

Abstract: The invention relates to a process for the fractionation and purification of mixtures of aromatic polyamines and to the use thereof.

Abstract: The present invention relates to an improved process for the preparation of toluidines. This process comprises the reductive deamination of 2,3-diaminotoluenes and/or 3,4-diaminotoluenes in the presence of one or more iron oxide catalyst.

Abstract: The invention relates to a process for the fractionation and purification of aromatic polyamine mixtures and the use thereof.

Abstract: The invention relates to a process for the fractionation and purification of aromatic polyamine mixtures and the use thereof.

Abstract: The invention relates to a process for the fractionation and purification of aromatic polyamine mixtures and to the use thereof.

Abstract: Aminobiphenyl (ABP) can be separated off from diphenylamine (DPA) by treating the DPA to be purified at elevated temperature with a substance in which oxygen is bonded by a double bond to a C atom, an N atom or another O atom and then separating off the DPA from the treated mixture.

Abstract: Disclosed herein is a stereospecific synthesis amenable to the large scale preparation of a hydrochloric acid addition salt of a chlorohydrin of the formula ##STR1## wherein R.sup.1 and R.sup.2 are amino protective groups and R.sup.3 is an amino acid side chain or a protected amino acid side chain. The synthesis involves reacting an aldehyde of the formula ##STR2## wherein R.sup.1, R.sup.2 and R.sup.3 are as defined hereinbefore with (chloromethyl)lithium at -20.degree. C. or below and contacting the resulting diastereoisomeric mixture of lithium alcoholates with aqueous hydrochloric acid to obtain a separable mixture of the hydrochloric acid addition salts of the chlorohydrin and its corresponding hydroxy diastereoisomer. The hydrochloric acid addition salt of the chlorohydrin is transformed readily into corresponding optionally amino-protected aminoepoxides; for example, 3(S)-(tert-butyloxycarbonylamino)-l,2(S)-epoxy-4-phenyl-butane.

Abstract: The present invention is directed to a process for reducing the nitrosamine content in a herbicide derived from dinitroaniline. The herbicide is treated with an aqueous solution of alkaline or ammonium persulfate in a proportion of at least 0.5% w/w relative to the weight of the herbicide to form an aqueous suspension. The suspension is heated to at least 70.degree. C., and the herbicide is separated from the suspension.

Abstract: A process for the purification of tertiary amines in a crude mixture contaminated with undesirable primary and secondary amines which may have only a slight variance in boiling point with respect to the tertiary amine, wherein the crude mixture of the tertiary amine is treated at temperatures which may range from 0.degree. to 200.degree. C. but preferably from 20 to 150.degree. C. and at pressures of from 1 to 200 bar but most preferably under atmospheric pressure with a carboxylate of the formula ##STR1## in which R.sup.4 and R.sup.5 are selected from the group consisting of C.sub.1 -C.sub.20 -alkyl, C.sub.3 -C.sub.12 -cycloalkyl, C.sub.4 -C.sub.20 -cycloalkylalkyl, and aryl or C.sub.7 -C.sub.20 -aralkyl, both optionally mono- to penta- substituted by C.sub.1 -C.sub.8 -alkyl, C.sub.3 -C.sub.8 -cycloalkyl, or C.sub.4 -C.sub.12 -cycloalkylalkyl, and R.sup.

Abstract: A process for the preparation of the unsaturated dinitroaniline, ethalfluralin having a level of nitrosamines lower than 0.5 ppm and essentially free from the compound of addition of halogenhydric acid on the methallyl double bond, by treatment with aqueous halogenhydric acid, wherein crude ethalfluralin is treated under agitation with an aqueous solution of hydrobromic acid in the presence of sulfamic acid and a sulfur compound selected from the group consisting of bisulfites, metabisulfites, hydrosulfites, sulfurous acid and gaseous sulfur dioxide.

Abstract: Methods are provided whereby an N-C-N compound is regenerated from a product of a sulfur scavenging reaction, in which said N-C-N compound removes a sulfur atom from a sulfur compound, to form the original N-C-N compound. The N-C-N compound is represented by the formula (I): ##STR1## The product includes a hetero compound having sulfur, carbon and nitrogen atoms in its backbone. In one embodiment, the product is mixed with (1) a nitrogen compound represented by the formula (II): ##STR2## and (2) an alkaline compound selected from alkali metal, alkaline earth metal and transition metal compounds, to form a solution, slurry or dispersion. The hetero compound is reacted with the nitrogen compound in the presence of the alkaline compound, such that a sulfur atom of the hetero compound is replaced by a nitrogen atom of the nitrogen compound. If necessary, the pH of the solution may be adjusted to about 8 to about 13 to facilitate the reaction. In alternative embodiments, the product also includes an amine complex.

Abstract: Diaminodiphenyl-compounds of the structure selected from: ##STR1## wherein R.sub.1 and R.sub.2 can be: H, --CH.sub.3, --C.sub.2 H.sub.5, --C.sub.3 H.sub.7, --C.sub.4 H.sub.9 or ##STR2## Y can be: C(CH.sub.3).sub.2, ##STR3## n=0; 1. are purified by distilling the crude product obtained under vacuum in one step, in the presence of one or more alkaline bases.

Abstract: Disclosed is a method for decolorizing alkylated diarylamines, which have been made using aluminum chloride catalyst, by mixing and optionally heating the colored diarylamine with clay, then separating the decolorized diarylamine from the clay. Alternatively, the alkylated diarylamines, which have been made using aluminum chloride catalyst, may be decolorized by passing the diarylamines through a filter medium comprising clay.

Abstract: A process for recovering both an amine and a volatile acid from an amine salt is disclosed. In the process, the amine salt is reacted with a non-volatile acid to liberate the volatile acid. Thermal decomposition of the resulting amine/non-volatile acid salt liberates the amine.

Abstract: A process for removing organic compounds, including nitro-hydroxy-aromatic compounds and amines, from alkaline wastewater, and in particular from wastewater generated in the production of nitrobenzene, dinitrobenzene, nitrotoluene and dinitrotoluene. The process involves distilling the alkaline wastewater steam at or near atmospheric pressure until it is concentrated five to twenty-five fold. The distillate includes water, which may be discharged to the environment, subjected to biological treatment, or recycled for use in the production process; and volatile organics, which are phase separated from the aqueous portion of the distillate and which may be recycled to the crude product stream. The concentrated residue from the distillation may be incinerated or subjected to biological treatment.

Abstract: Waste or scrap polyurethane may be conveniently and economically converted to useful active-hydrogen containing polyethers and polyamines by contacting the polyurethane with water, strong base, and an activating agent such as a quaternary ammonium compound containing at least 15 carbon atoms or an organic sulfonate containing at least 7 carbon atoms. The activating agent helps to accelerate the rate of base catalyzed hydrolysis.