Abstract: Lactams, notably ?-caprolactam, are prepared from alkyl cyanovalerates, themselves obtained from unsaturated nitrile compounds, by contacting same, in gaseous state, with hydrogen in the presence of hydrogenation/cyclization catalysts, and then condensing the gas stream thus formed, without intermediate separation of any alkyl aminocaproate, and recovering lactam produced therefrom.

Abstract: The present invention relates to a process for the preparation of dinitriles by hydrocyanation of unsaturated nitrile compounds in the presence of a catalyst based on a metal element in the zero oxidation state and on organophosphorus ligands;the invention relates more particularly to a process for the recovery from the hydrocyanation medium of a catalyst for the hydrocyanation of unsaturated nitrites to dinitriles. It consists in controlling the concentration of unsaturated nitrites in the reaction medium resulting from the hydrocyanation reaction in order to obtain a concentration by weight of unsaturated nitrites of less than 20% in the said medium, and in then feeding the said medium to a stage of settling into two upper and lower phases. The lower phase comprises most of the catalytic system, while the upper phase is composed essentially of the dinitriles.

Abstract: Amino compounds are continuously prepared by hydrogenation of nitrile compounds in the presence of a catalyst, and more particularly diamines are prepared by the continuous hydrogenation of dinitrile compounds in the presence of a Raney metal catalyst and in the absence of an alcoholic solvent; the subject process includes extracting a portion of the catalyst present in the reaction medium, the extracted portion of the catalyst is submitted to a regeneration for providing a catalyst having a catalytic activity lower than that of a fresh catalyst but still high and the regenerated catalyst is recycled to the reaction medium together with fresh catalyst according to a predetermined ratio, whereby the consumption of catalyst is reduced per ton of amines produced.

Abstract: Hydrocarbon compounds having at least one nitrile function are converted into compounds having at least one carboxylic function by hydrating the nitrile functions into amide functions by reaction with water in the presence of a strong inorganic acid, and then hydrolyzing the amide functions into carboxylic functions by reaction with water and a strong inorganic acid; the carboxylic compounds thus obtained can be esterified into diesters, advantageously diester solvents.

Abstract: The present invention relates to a process for the manufacture of dinitrile compounds by double hydrocyanation of an olefin. It relates particularly to a process for the manufacture of dinitrile compounds by double hydrocyanation of an olefin present in a mixture of hydrocarbons, such as a petroleum fraction and more particularly still a petroleum fraction known under the name of C4 fraction. The process of the invention comprises a sequence of stages for the separation of the various compounds which makes it possible to remove the byproducts, such as the products from the trimerization of alkynes, present in the C4 fraction and thus to prevent their accumulation in the hydrocyanation reactors.

Abstract: Hydrocarbon-based compounds containing at least one nitrile function are converted into compounds containing at least one carboxylic function, and into ester compounds from the carboxylic compounds thus obtained; such conversion entails reacting the nitrile compound with a hydroxyl basic compound in solution in a solvent at a temperature of between 80 and 150° C., in eliminating the ammonia formed, in reacting the salt obtained with a mineral acid, and then in recovering the compound containing at least one carboxylic function and, optionally, esterifying the acids obtained by reaction with an alcohol.

Abstract: Diester compounds are prepared from imide/dinitrile compounds employing a vapor-phase hydrolysis of dinitrile compounds in the presence of alcohol, more particularly from branched dinitrile compounds, such as methylglutaronitrile or branched dinitrile compounds obtained as by-products in a process for the production of adiponitrile by hydrocyanation of butadiene.

Abstract: The present invention relates to a process for the hydrocyanation of unsaturated compounds to unsaturated mononitrile compounds or to dinitrile compounds; It relates more particularly to a process for the manufacture of dinitriles by double hydrocyanation of diolefins, such as butadiene, comprising a recovery and separation of the catalytic system. The process for the manufacture of dinitriles of the invention by hydrocyanation of unsaturated compounds, comprising at least one stage of hydrocyanation in the presence of a catalytic system comprising an organometallic complex formed by one or more monodentate organophosphite ligands and one or more bidentate organophosphorus ligands and optionally a promoter of Lewis acid type, comprises at least one stage of separation by distillation of a reactant used in the process or of a compound formed by the reaction from a medium comprising the said catalytic system.

Abstract: Lactams, notably ?-caprolactam, are prepared from alkyl cyanovalerates, themselves obtained from unsaturated nitrile compounds, by contacting same, in gaseous state, with hydrogen in the presence of hydrogenation/cyclization catalysts, and then condensing the gas stream thus formed, without intermediate separation of any alkyl aminocaproate, and recovering lactam produced therefrom.

Abstract: The invention relates to a method for the preparation of cyclohexanone from cyclohexane. The invention relates more particularly to a method for the production of cyclohexane whose impurity content enables cyclohexanone to be used as a raw material for the production of e-caprolactam. The inventive method consists in treating the mixture of cyclohexanol/cyclohexanone arising from oxidation of cyclohexane by oxygen in a dehydrogenation stage in order to transform cyclohexanol into cyclohexanone and the impurities present such as cyclopentenal. The inventive method makes it possible to obtain highly pure cyclohexanone which is compatible when used as a raw material in the synthesis of e-caprolactam.

Abstract: The present invention relates to a process for the manufacture of dinitrile compounds by double hydrocyanation of an olefin. It relates particularly to a process for the manufacture of dinitrile compounds by double hydrocyanation of an olefin present in a mixture of hydrocarbons, such as a petroleum fraction and more particularly still a petroleum fraction known under the name of C4 fraction. The process of the invention comprises a sequence of stages for the separation of the various compounds which makes it possible to remove the byproducts, such as the products from the trimerization of alkynes, present in the C4 fraction and thus to prevent their accumulation in the hydrocyanation reactors.

Abstract: The present invention relates to a process for the manufacture and separation of dinitrile compounds. It relates more particularly to a process for the manufacture and separation of dinitrile compounds from a medium originating from the hydrocyanation of unsaturated mononitriles. The invention consists in feeding the medium comprising the dinitriles to a distillation column and then recovering the purified dinitriles as intermediate fraction, the heavy products being removed as column tail fraction and the light products, including the unsaturated mononitriles, being recovered as top fraction.

Abstract: Hexamethylenediamine and aminocapronitrile are simultaneoussly produced by hemihydrogenation of adiponitrile, which includes a stage of separation of the hexamethylenediamine from the hydrogenate by distillation of the hexamethylenediamine, the distillation of the hexamethylenediamine being carried out from the hydrogenate containing a free acid and/or an alkali metal or ammonium acid salt, whereby a top fraction A recovered at the column top of the stage of distillation of the hexamethylenediamine is essentially crude hexamethylenediamine and a small amount of THA; the amount of THA (tetrahydroazepine) present in the crude hexamethylenediamine constitutes a small proportion of the THA present in the hydrogenate.

Abstract: A process for the hydrogenation of compounds comprising nitrile or nitro functional groups to amine, aminonitrile or aminonitro compounds is provided. The process can be a continuous process conducted in the presence of a heterogeneous hydrogenation catalyst in divided form and a basic compound. The reaction can be conducted in a stirred reactor comprising an external loop for circulating the reaction mixture, allowing one portion of the hydrogenated products to be separated without withdrawing the catalyst, by using tangential filtration. The process may be especially useful in the hydrogenation of adiponitrile to an aminocapronitrile/hexamethylenediamine mixture.

Abstract: A method and a plant are disclosed for purifying lactams, particularly lactams obtained by cyclizing hydrolysis of aminonitrile. The purification of ?-caprolactam obtained by cyclizing hydrolysis of aminocapronitrile is described which includes eliminating the ammonia from the reaction medium of the hydrolysis, then recovering the lactam from said medium in purified form. The recovery is carried out by performing at least a distillation of the lactam in the presence of a base producing optionally a fronts fraction comprising compounds more volatile than the lactam, a fraction comprising the lactam to be recovered to the degree of desired purity and a distillation tails comprising the lactam and compounds less volatile than the lactam. The distillation tails are treated by various processes such as evaporation in thin layers to recover the major part of the caprolactam and recycling the latter in the purification process.

Abstract: A method and a plant are disclosed for purifying lactams, particularly lactams obtained by cyclizing hydrolysis of aminonitrile. The purification of ?-caprolactam obtained by cyclizing hydrolysis of aminocapronitrile is described which includes eliminating the ammonia from the reaction medium of the hydrolysis, then recovering the lactam from said medium in purified form. The recovery is carried out by performing at least a distillation of the lactam in the presence of a base producing optionally a fronts fraction comprising compounds more volatile than the lactam, a fraction comprising the lactam to be recovered to the degree of desired purity and a distillation tails comprising the lactam and compounds less volatile than the lactam. The distillation tails are treated by various processes such as evaporation in thin layers to recover the major part of the caprolactam and recycling the latter in the purification process.

Abstract: The present invention relates to the hemihydrogenation of dinitriles to corresponding aminonitriles.

Abstract: The invention relates to a method for the preparation of cyclohexanone from cyclohexane. The invention relates more particularly to a method for the production of cyclohexane whose impurity content enables cyclohexanone to be used as a raw material for the production of e-caprolactam. The inventive method consists in treating the mixture of cyclohexanol/cyclohexanone arising from oxidation of cyclohexane by oxygen in a dehydrogenation stage in order to transform cyclohexanol into cyclohexanone and the impurities present such as cyclopentenal. The inventive method makes it possible to obtain highly pure cyclohexanone which is compatible when used as a raw material in the synthesis of e-caprolactam.

Abstract: The present invention relates to a process for the preparation of dinitriles by hydrocyanation of unsaturated nitrile compounds in the presence of a catalyst based on a metal element in the zero oxidation state and on organophosphorus ligands;the invention relates more particularly to a process for the recovery from the hydrocyanation medium of a catalyst for the hydrocyanation of unsaturated nitrites to dinitriles. It consists in controlling the concentration of unsaturated nitrites in the reaction medium resulting from the hydrocyanation reaction in order to obtain a concentration by weight of unsaturated nitrites of less than 20% in the said medium, and in then feeding the said medium to a stage of settling into two upper and lower phases. The lower phase comprises most of the catalytic system, while the upper phase is composed essentially of the dinitriles.

Abstract: The present invention relates to a process for the hydrocyanation of unsaturated compounds to unsaturated mononitrile compounds or to dinitrile compounds; It relates more particularly to a process for the manufacture of dinitriles by double hydrocyanation of diolefins, such as butadiene, comprising a recovery and separation of the catalytic system. The process for the manufacture of dinitriles of the invention by hydrocyanation of unsaturated compounds, comprising at least one stage of hydrocyanation in the presence of a catalytic system comprising an organometallic complex formed by one or more monodentate organophosphite ligands and one or more bidentate organophosphorus ligands and optionally a promoter of Lewis acid type, comprises at least one stage of separation by distillation of a reactant used in the process or of a compound formed by the reaction from a medium comprising the said catalytic system.