摘要:
The present invention relates to an expandable polyamide composition and to a polyamide foam obtained therefrom. This composition comprises a compound comprising at least one isocyanate function, a polyamide and a compound comprising at least one carboxylic acid function. The invention also relates to a process for preparing a polyamide foam from this composition.
摘要:
A process is described for purifying lactams, in particular the lactams obtained by cyclizing hydrolysis of an aminoalkylnitrile, and more particularly to the purification by crystallization of ε-caprolactam obtained by cyclizing hydrolysis of aminocapronitrile. This crystallization is carried out on the cyclization reaction medium after hydrogenation, removal of volatile compounds, and treatment with an ion-exchange resin.
摘要:
The present invention relates to a process of hydrocyanation of ethylenically unsaturated organic compounds to compounds having at least one nitrile function, particularly the hydrocyanation of diolefins such as butadiene, or of substituted olefins such as alkene nitrites such as pentenenitriles; the subject hydrocyanation is carried out in the presence of a catalytic system comprising a metallic element and mono- and pluri-dentate organophosphorus ligands.
摘要:
The present invention relates to the manufacture of nitrile compounds from unsaturated organic compounds by reaction with hydrogen cyanide. It relates more particularly to the manufacture of nitrile compounds of use in the synthesis of adiponitrile, an important chemical intermediate in the manufacture of major chemical compounds, such as hexamethylenediamine and ε-caprolactam. The invention provides a process for the manufacture of organic compounds comprising at least one nitrile functional group by carrying out a hydrocyanation reaction between hydrogen cyanide and an organic compound comprising at least one ethylenic unsaturation. This reaction is carried out in the presence of a catalytic system comprising a metal element chosen from the group consisting of nickel, platinum and palladium and an organophosphorus ligand, the reaction medium additionally comprising an ionic liquid in the liquid state at least at the temperature at which the hydrocyanation reaction is carried out.
摘要:
The present invention relates to a process for the oxidation of hydrocarbons, in particular of branched or unbranched saturated aliphatic hydrocarbons, of cycloaliphatic or alkylaromatic hydrocarbons or of alcohols and/or ketones, to acid or polyacid compounds.It relates more particularly to the oxidation, by an oxidizing agent comprising molecular oxygen, of cyclohexane and/or of cyclohexanol and/or cyclohexanone to adipic acid, in the presence of an aromatic organic acid and a manganese-based catalyst. The yield and selectivity for adipic acid are of a high level with respect to those obtained with other solvents and catalysts.
摘要:
A method and a plant are disclosed for purifying lactams, particularly lactams obtained by cyclizing hydrolysis of aminonitrile. The purification of ε-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. The method and plant enables a high rate of recovery of the caprolactam contained in the hydrolysis medium, while observing required criteria of purity.
摘要:
The present invention relates to a process for the preparation of β- or γ-unsaturated or saturated carboxylic acids.It relates more particularly to the hydroxycarbonylation of an organic compound comprising a conjugated unsaturation, such as butadiene, by the action of carbon monoxide and water in the presence of a palladium-based catalyst. The carboxylic acids thus obtained are preferably pentenoic acids. According to the invention, the reaction medium after the end of the hydroxycarbonylation stage is treated with hydrogen to reduce the palladium present in the 2+ oxidation state to palladium in the zero oxidation state and the precipitated palladium is recovered.
摘要:
The present invention concerns a process for hydrocyanating ethylenically unsaturated organic compounds to compounds containing at least one nitrile function. It relates more particularly to the hydrocyanation of diolefins such as butadiene or of substituted olefins such as alkenenitriles, for instance pentenenitriles. According to the process of the invention the reaction is implemented in the presence of a metal complex catalyst comprising a transition metal such as nickel and an organic ligand.
摘要:
The present invention concerns a process for hydrocyanating ethylenically unsaturated organic compounds to compounds containing at least one nitrile function. It relates more particularly to the hydrocyanation of diolefins such as butadiene or of substituted olefins such as alkenenitriles, for instance pentenenitriles. According to the process of the invention the reaction is implemented in the presence of a metal complex catalyst comprising a transition metal such as nickel and an organic ligand.