Patents Assigned to Rhodia Fiber and Resin Intermediates
  • Patent number: 6417375
    Abstract: The present invention relates to novel water-soluble furylphosphines. It also relates to organometallic complexes comprising these furylphosphines and to the use of such complexes. It also relates to the process for the preparation of the water-soluble furylphosphines.
    Type: Grant
    Filed: April 13, 2001
    Date of Patent: July 9, 2002
    Assignee: Rhodia Fiber & Resin Intermediates
    Inventors: Francois Mathey, Philippe Savignac, Frederic Eymery, Paolo Burattin
  • Patent number: 6384283
    Abstract: The present invention relates to a process for the preparation of aminonitrile and of diamine by catalytic hydrogenation of dinitrile. It consists of a process for the preparation of aminonitrile and of diamine by catalytic hydrogenation of aliphatic dinitrile having from 3 to 12 carbon atoms, characterized in that the final reaction mixture, the catalyst of which has been separated beforehand, is acidified by addition of a sufficient amount of an inorganic or organic acid, before being subjected to an operation of distillation of the products of the reaction and of the unconverted dinitrile. It relates more particularly to the preparation of 6-aminocapronitrile and of hexamethylenediamine by hydrogenation of adiponitrile. The 6-aminocapronitrile can be hydrolysed in the liquid phase or in the gas phase to result in caprolactam. The hexamethylenediamine can be used very particularly to prepare polyamide-6,6 by reaction with adipic acid.
    Type: Grant
    Filed: January 26, 2001
    Date of Patent: May 7, 2002
    Assignee: Rhodia Fiber & Resin Intermediates
    Inventor: Philippe Leconte
  • Patent number: 6372942
    Abstract: The invention discloses pentenoic acid hydroxycarbonylation into adipic acid. More particularly, it concerns one pentenoic acid hydroxycarbonylation method involving reaction water and carbon monoxide, in the presence of a catalyst comprising at least rhodium and/or iridium and an iodinated or brominated catalytic promoter. In the method, the catalyst is derived at least in part from a previous pentenoic acid hydroxycarbonylation operation. The reaction is effected in the presence of an amount of branched carboxylic diacids having 6 carbon atoms not exceeding 200 grams per kilogram reaction mixture.
    Type: Grant
    Filed: March 17, 1999
    Date of Patent: April 16, 2002
    Assignee: Rhodia Fiber & Resin Intermediates
    Inventors: Jacques Brivet, Eric B. Henriet, Carl Patois, Robert Perron
  • Patent number: 6312578
    Abstract: The invention concerns a method for extracting by electrodialysis a compound comprising at least amine functions capable of protonation from a liquid medium. More particularly it concerns a method for extracting, and separating at least the monomers comprising amine functions capable of protonation from a liquid medium derived from the hydrolysis of polyamides. The method of extraction from a liquid medium consists in subjecting to protonation the amine function(s) of the compounds to be extracted by adjusting the pH of the medium and in separating the compounds by passing them through a cationic membrane under the effect of an electric current. The invention is particularly applicable in processes for the chemical stabilisation of polyamides such as the PA 66 PA 6.
    Type: Grant
    Filed: September 7, 1999
    Date of Patent: November 6, 2001
    Assignee: Rhodia Fiber & Resin Intermediates
    Inventors: Edith Canivenc, Dominique Horbez
  • Patent number: 6232488
    Abstract: The present invention relates to a process for the hydrogenation of aliphatic dinitriles at least partly into corresponding aminonitriles. More specifically, the invention consists of a continuous process for the hydrogenation of dinitrile, at least partly into corresponding aminonitrile, in the presence of a hydrogenation catalyst which is not dissolved in the reaction medium, characterized in that it is carried out in apparatus comprising means for the continuous separation of the hydrogenate and of the catalyst in a zone in which the gas-liquid transfer is limited or zero, the said separation and the recycling of the catalyst being carried out in a period of time less than or equal to 30 minutes.
    Type: Grant
    Filed: September 19, 2000
    Date of Patent: May 15, 2001
    Assignee: Rhodia Fiber and Resin Intermediates
    Inventors: Vincent Boschat, Philippe Leconte, Daniel Rochette, Lionel Sever
  • Patent number: 6222069
    Abstract: The invention discloses a method for purifying adipic acid in water. More precisely it discloses an improvement in adipic acid crystallization or recrystallization in water, characterised in that the said crystallization or recrystallization is effected in presence of a strong proton acid and/or in the presence of carbon monoxide. This crystallization or recrystallization particularly enables the content of metal catalyst traces in the adipic acid to be reduced.
    Type: Grant
    Filed: March 17, 1999
    Date of Patent: April 24, 2001
    Assignee: Rhodia Fiber and Resin Intermediates
    Inventors: Eric B. Henriet, Philippe Leconte, Carl Patois, Robert Perron
  • Patent number: 6214190
    Abstract: The present invention relates to a process for isolating, by membrane electrodialysis, a catalyst from a solution containing it. More precisely, it relates to the isolation of a catalyst used in a homogeneous phase molecular oxidation reaction. The invention consists of a process for isolating a homogeneous catalyst dissolved in a mixture also containing at least one aliphatic diacid, characterized in that the catalyst contains cobalt and the isolation is performed by membrane electrodialysis.
    Type: Grant
    Filed: February 8, 1999
    Date of Patent: April 10, 2001
    Assignee: Rhodia Fiber and Resin Intermediates
    Inventors: Eric Fache, Dominique Horbez, Philippe Leconte
  • Patent number: 6204379
    Abstract: The present invention concerns the aminomethylation of pentenoic acid derivatives, by reaction with carbon monoxide, hydrogen and ammonia, for preparing caprolactam. More precisely, it is directed to a method for preparing caprolactam wherein the aminomethylation of pentenoic acid derivatives is carried out by reaction with carbon monoxide, hydrogen, and ammonia, at a temperature higher than 30° C. and in the presence of a catalyst with a base of at least one metal of Group VIII of the Periodic Table.
    Type: Grant
    Filed: July 27, 1999
    Date of Patent: March 20, 2001
    Assignee: Rhodia Fiber & Resin Intermediates
    Inventors: Carl Patois, Michel Spagnol
  • Patent number: 6147256
    Abstract: Carboxylic acids, e.g., adipic acid, are more selectively prepared by oxidizing cyclohexane with oxygen or an oxygen-containing gas, in liquid phase, in a solvent reaction medium which comprises a polar protic or aprotic solvent, and also in the presence of a catalytically effective amount of catalyst values dissolved in said solvent reaction medium, the catalyst values comprising at least one solvent-soluble cobalt compound and at least one solvent-soluble chromium compound.
    Type: Grant
    Filed: April 10, 1998
    Date of Patent: November 14, 2000
    Assignee: Rhodia Fiber and Resin Intermediates
    Inventors: Michel Costantini, Eric Fache
  • Patent number: 6100396
    Abstract: A method for purifying lactams by liquid-liquid extraction and/or processing with an ion exchange resin is disclosed. The method is useful for purifying lactams produced by the cyclising vapour-phase hydrolysis of an aliphatic aminonitrile, and comprises removing the major part of the ammonia before subjecting the lactam to liquid-liquid extraction by means of a solvent including an acidic solvent and/or contacting said lactam with a cation exchange resin. In most applications of the lactam, it is preferable to carry out a hydrogenation step on the compounds of the lactam solution comprising unsaturations, prior to or in addition to the liquid-liquid extraction step and/or the acidic resin contact step. The purification method may also include an oxidation step in addition to or instead of the hydrogenation step. Said method is preferably combined with a distillation step in the presence of a base.
    Type: Grant
    Filed: April 23, 1999
    Date of Patent: August 8, 2000
    Assignee: Rhodia Fiber and Resin Intermediates
    Inventors: Hubert Gayet, Philippe Leconte, Philippe Perrona
  • Patent number: 6083869
    Abstract: The present invention relates to a process for the preparation of mixed vanadium, antimony and iron oxides and to their use as catalysts for the ammoxidation of alkanes. The process for the preparation of a mixed oxide defined above is characterized in that:respective vanadium, antimony and iron compounds are dissolved in at least one saturated alcohol or in water,the alcoholic .epsilon.olution or the aqueous solution thus obtained is brought into contact with an aqueous solution containing an ammonium salt, in order to precipitate the mixed oxide,the mixed oxide obtained is separated and calcined.
    Type: Grant
    Filed: June 11, 1998
    Date of Patent: July 4, 2000
    Assignee: Rhodia Fiber and Resin Intermediates
    Inventors: Stefania Albonetti, Gilbert Blanchard, Paolo Burattin, Fabrizio Cavani, Ferruccio Trifiro
  • Patent number: 6069246
    Abstract: The present invention relates to the treatment of lactams obtained directly from their synthesis process, avoiding the formation of oligomers as far as possible. The invention consists, more precisely, of a process for treating a lactam using the reaction flow obtained from a cyclizing hydrolysis of an aminonitrile, characterized in that the reaction flow leaving the hydrolysis reactor is cooled, over a period of less than or equal to 1 hour, to a temperature below or equal to 150.degree. C. before it is fractionated.
    Type: Grant
    Filed: July 27, 1999
    Date of Patent: May 30, 2000
    Assignee: Rhodia Fiber & Resin Intermediates
    Inventors: Henri Chiarelli, Philippe Leconte