Abstract: The present invention relates to a process for the purification of fluorinated olefins, in particular hexafluoro-1,3-butadiene, comprising a step wherein a liquid mixture comprising hexafluoro-1,3-butadiene in liquid phase is contacted with at least one adsorbent having an average pore size of less than 10 ?.

Abstract: The present invention concerns a method for preparing an oxysulphide and fluorinated derivative of formula (III) Ea-SO3R (III) that comprises bringing a compound of formula (II) Ea-SOOR (II)—Ea representing the fluorine atom or a group having 1 to 10 carbon atoms chosen from the fluoroalkyls, the perfluoroalkyls and the fluoroalkenyls; and—R representing hydrogen, a monovalent cation or an alkyl group; into contact, in the presence of a polar aprotic organic solvent, with an oxidising agent.

Abstract: A process for extraction of ferulic acid present in an aqueous phase, obtained by treatment of at least one plant material, and also containing polysaccharides, is described, said process comprising at least the following steps: 1) the treatment of said plant material followed by a solid/liquid separation to recover a solid phase and an aqueous liquid phase comprising the ferulic acid and said polysaccharides, 2) the treatment of said liquid phase to selectively separate, on the one hand, the polysaccharides and, on the other hand, the ferulic acid present in an aqueous fraction, 3) the concentration of said aqueous fraction containing the ferulic acid so as to recover a ferulic acid-concentrated stream, 4) the recovery of the ferulic acid in solid form.

Abstract: The invention relates to a natural vanillin, which is in the form of an amorphous solid of which the color, in ethanolic solution at 10% by weight, is less than or equal to 200 Hazen, preferably less than or equal to 100 Hazen.

Abstract: The invention concerns a method for preparing an oxysulphide and fluorinated derivative, said method comprising the reacting, in the presence of an organic solvent, of: i) at least one compound of formula Ea-COOR (I), in which Ea represents the fluorine atom or a group having 1 to 10 carbon atoms chosen from fluoroalkyls, perfluoroalkyls and fluoroalkenyls and R represents hydrogen, a monovalent cation or an alkyl group, and ii) a sulphur oxide, said method being such that the initial molar ratio (sulphur oxide/compound of formula (I)) is less than 0.4 and the concentration of sulphur oxide dissolved in the reaction medium is kept constant for the entire duration of the reaction to a value of between 0.2% and 3% by weight by means of continually adding said sulphur oxide to the reaction medium.

Abstract: The invention relates to a natural vanillin, which is in the form of an amorphous solid of which the color, in ethanolic solution at 10% by weight, is less than or equal to 200 Hazen, preferably less than or equal to 100 Hazen.

Abstract: The invention relates to a method for the purification of natural vanillin, comprising at least one step in which the natural vanillin is evaporated.

Abstract: The invention concerns a method for preparing an oxysulphide and fluorinated derivative, said method comprising the reacting, in the presence of an organic solvent, of: i) at least one compound of formula Ea-COOR (I), in which Ea represents the fluorine atom or a group having 1 to 10 carbon atoms chosen from fluoroalkyls, perfluoroalkyls and fluoroalkenyls and R represents hydrogen, a monovalent cation or an alkyl group, and ii) a sulphur oxide, said method being such that the initial molar ratio (sulphur oxide/compound of formula (I)) is less than 0.4 and the concentration of sulphur oxide dissolved in the reaction medium is kept constant for the entire duration of the reaction to a value of between 0.2% and 3% by weight by means of continually adding said sulphur oxide to the reaction medium.

Abstract: A process for extraction of ferulic acid present in an aqueous phase, obtained by treatment of at least one plant material, and also containing polysaccharides, is described, said process comprising at least the following steps: 1) the treatment of said plant material followed by a solid/liquid separation to recover a solid phase and an aqueous liquid phase comprising the ferulic acid and said polysaccharides, 2) the treatment of said liquid phase to selectively separate, on the one hand, the polysaccharides and, on the other hand, the ferulic acid present in an aqueous fraction, 3) the concentration of said aqueous fraction containing the ferulic acid so as to recover a ferulic acid-concentrated stream, 4) the recovery of the ferulic acid in solid form.

Abstract: The invention relates to a method for the purification of natural vanillin, comprising at least one step in which the natural vanillin is evaporated.

Abstract: A process for phosgenating an amine comprising employing a plug-flow type reactor with internal recycle is disclosed. The process can be continuous, which makes it possible to prepare, in a single stage, a (poly)isocyanate with a good yield, without formation of byproducts and on simplifying the plant in order to carry out the process so as to promote safety.

Abstract: The invention relates to a composition and a method of preparing one such composition and an isocyanatoalkoxysilane; the polyisocyanate composition contains at least two different oligomeric compounds comprising at least three units and at most five units selected from aminoalkylsilane units and diamine units and at least one function selected from isocyanate functions and from those derived therefrom, the aforementioned compounds having at least two aminoalkylsilane units and another compound having at least two diamine units; the invention is suitable for coatings.

Abstract: The invention relates to a process for the synthesis of a polyisocyanate composition comprising acylureas. According to the invention, a starting composition comprising a compound having at least two isocyanate functional groups is subjected to a reaction with at least two acid functional groups, with at least one of the acid functional groups having a pKa value of less than or equal to 3, and at least one of the acid functional groups having a pKa value of more than 3 and less than or equal to 6, at a temperature at least equal to 50 ° C., wherein the acid functional group having a pKa value of less than or equal to 3 and the acid functional group having a pKa value of more than 3 and less than or equal to 6 are present on two different acids or on the same acid.

Abstract: A process for phosgenating an amine comprising employing a plug-flow type reactor with internal recycle is disclosed. The process can be continuous, which makes it possible to prepare, in a single stage, a (poly)isocyanate with a good yield, without formation of byproducts and on simplifying the plant in order to carry out the process so as to promote safety.

Abstract: A low viscosity polyisocyanate composition containing at least one isocyanate dimer having a uretidinedione unit is prepared from a reaction medium containing at least one isocyanate monomer in which the isocyanate groups are borne by sp3 carbon atoms. The reaction medium is heated, in the absence of a dimerization catalyst, to a temperature of at least 50° C. and not more than 200° C. for a period of not more than 24 hours.

Abstract: The invention relates to a composition and a method of preparing one such composition and an isocyanatoalkoxysilane; the polyisocyanate composition contains at least two different oligomeric compounds comprising at least three units and at most five units selected from aminoalkylsilane units and diamine units and at least one function selected from isocyanate functions and from those derived therefrom, the aforementioned compounds having at least two aminoalkylsilane units and another compound having at least two diamine units; the invention is suitable for coatings.

Abstract: The invention relates to a composition and a method of preparing one such composition and an isocyanatoalkoxysilane; the polyisocyanate composition contains at least two different oligomeric compounds comprising at least three units and at most five units selected from aminoalkylsilane units and diamine units and at least one function selected from isocyanate functions and from those derived therefrom, the aforementioned compounds having at least two aminoalkylsilane units and another compound having at least two diamine units; the invention is suitable for coatings.

Abstract: The invention relates to a method for the synthesis of a polyisocyanate composition comprising acylureas. According to the invention, an initial composition containing derivatives comprising at least two isocyanate functions is subjected to the action of at least two acids, whereby at least one of said acids is a strong acid (pKa=3) and at least one is a medium strength acid (3=pKa=6), at a temperature that is equal to or greater than 50° C.; the invention is suitable for coatings.

Abstract: A method is described for preparing a tricondensate polyfunctional isocyanate composition, preferably having at least an isocyanurate and/or biuret group, which includes adding to a tricondensate polyfunctional isocyanate, or a mixture of different tricondensate polyfunctional isocyantes, obtained by (cyclo)condensation, in particular (cyclo)trimerization of one or several identical or different isocyanate monomers and optionally of another monomer, an allophanate of one or several identical or different isocyanates, or a mixture of different allophanates. The isocyanates or isocyanate monomer mixtures used for preparing the polyfunctional isocyanate(s) may be identical to or different from the isocyanate(s) or isocyanate mixture used for preparing the allophanate(s).

Abstract: The invention relates to a method for the synthesis of a polyisocyanate composition comprising acylureas. According to the invention, an initial composition containing derivatives comprising at least two isocyanate functions is subjected to the action of at least two acids, whereby at least one of said acids is a strong acid (pKa=3) and at least one is a medium strength acid (3=pKa=6), at a temperature that is equal to or greater than 50° C.; the invention is suitable for coatings.