Abstract: The invention relates to a process for treating an organic solution comprising cyclohexanone oxime, cyclohexanone and an organic solvent, said process comprising distilling the organic solution such as to obtain (i) a first product comprising organic solvent, (ii) a second product comprising cyclohexanone and (iii) a third product comprising cyclohexanone oxime; and feeding the second product to a cyclohexanone oxime synthesis zone in which hydroxylammonium is reacted with cyclohexanone to form cyclohexanone oxime.

Abstract: The invention relates to a process for treating an aqueous medium containing cyclohexanone oxime and cyclohexanone, said process comprising stripping the aqueous medium with steam, wherein said stripping is carried out at a pressure higher than 0.11 MPa. The invention also relates to a process for the preparation of cyclohexanone oxime, which involves stripping at a pressure higher than 0.11 MPa.

Abstract: The invention relates to a process for the preparation of hydroxylammonium, said process comprising the steps of: a) feeding gaseous hydrogen to a reaction mixture, said reaction mixture comprising an aqueous reaction medium and a gaseous phase; b) catalytically reducing, in said reaction mixture, nitrate or nitrogen oxide with hydrogen to form the hydroxylammonium; c) withdrawing a gas mixture from the reaction mixture, said gas mixture comprising gaseous hydrogen and gaseous non-hydrogen compounds; d) separating at least part of the gaseous non-hydrogen compounds from the gas mixture to obtain a hydrogen-enriched gas; and e) passing the hydrogen-enriched gas to a hydrogenation zone.

Abstract: A new type of poly-2-pyrrolidone suitable for melt spinning and a process for its preparation. The new poly-2-pyrrolidone is characterized in that the polymer in the virgin state has a relative viscosity (1 gram of polymer in 100 ml of 96% sulphuric acid at 20.degree. C.) of between 2.2 and 7.0, shows a weight loss of less than 5% by weight when heated from 20.degree. C. to the onset temperature of thermal degradation at a rate 4.degree. C. per minute, the ratio between the relative viscosities after and before melt spinning ranges between 0.50:1 and 0.95:1, and the relative viscosity after melt spinning is at least 1.90. The new poly-2-pyrrolidone is prepared by polymerization of 2-pyrrolidone in the presence of an anionic catalyst and an accelerator wherein N-(2-caprolactim)-caprolactam is used as the accelerator in an amount of between 0.05 and 5.0 mole percent relative to the monomer, and the polymerization is carried out at a temperature of between about 25.degree. and 70.degree. C.

Abstract: An improved, consistent quality anionic catalyst for polymerizing pyrrolidone, optionally mixed with up to 25% of another copolymerizable lactam, is disclosed in which an alkali metal pyrrolidonate, prepared by reacting an alkali metal hydroxide or alkoxide with a molar excess of pyrrolidone, is heated for at least 5 hours at 100.degree.-175.degree. C. in the absence of water and air. Reproduceable results are obtained when the catalyst so heated is used to polymerize pyrrolidone.

Abstract: Polypyrrolidone polymers and copolymers are obtained by polymerizing 2-pyrrolidone, optionally with another lactam, in the presence of a catalyst and accelerator, first in the mass until at least 10% of the monomer is converted but the reaction product is still capable of suspension, then completing the desired degree of polymerization by suspending the reaction mixture in an inert liquid dispersion agent that does not dissolve the desired polymer. Relatively high molecular weight polymers are prepared in a short amount of time using this two-stage procedure.