Abstract: A continuous process is provided for recovering caprolactam from aqueous caprolactam product which includes (i) caprolactam, (ii) impurities, and (iii) water by (a) adding alkali hydroxide to the aqueous caprolactam product, in an amount of not more than 100 mmol alkali hydroxide per kg of caprolactam; (b) reacting at least part of the added alkali hydroxide to form alkali amino caproate, to obtain a caproate-enriched caprolactam product; and (c) distilling the caproate-enriched caprolactam product at reduced pressure.

Abstract: The invention relates to a process for the preparation of a polyamide comprising at least a step in which a composition that comprises at least (a) a primary aminocarbonamide and (b) an aminocarboxylic acid and/or a lactam is polymerised, said composition comprising at least (a) 10-90 wt. % primary aminocarbonamide; (b) 10-90 wt. % aminocarboxylic acid and/or lactam; (c) 0-4 wt. % water; the amounts being relative to the sum of the compounds (a+b+c). Preferably the sum of the compounds (a+b+c) is at least 75 wt. % of the total composition, more preferably 85 wt. %, most preferably 90 wt. %. The polyamide obtained with the process has a &eegr;rel of more than 2.2. The process is eminently suitable for the preparation of polyamide-6 (polycapronamide) from a composition comprising 6-aminocapronamide, 6-aminocaproic acid and/or &egr;-caprolactam. This composition is preferably obtained via the reductive amination of a 5-formylyalerate ester, preferably 5-formylmethylvalerate in water.

Abstract: The invention relates to a process for the separation of a ketoxime or aldoxime from a ketoxime- or aldoxime-containing amide mixture in which the ketoxime or aldoxime is separated from the amide mixture by distillation. This has proved to be a very simple and direct method for separating the ketoxime and/or aldoxime from the desired amide.

Abstract: The invention relates to a process for the preparation of a polyamide comprising at least a step in which a composition that comprises at least (a) a primary aminocarbonamide and (b) an aminocarboxylic acid and/or a lactam is polymerised, said composition comprising at least

Abstract: Process for the preparation of &egr;-caprolactam comprising treating 6-aminocaproic acid 6-aminocaproate ester, 6-aminocaproamide, oligomers or polymers of these compounds or mixtures comprising at least two of these compounds in a cyclisation reactor in the presence of superheated steam in which a gaseous product stream comprising &egr;-caprolactam, lights and heavies is obtained, wherein the product stream, after condensation and at least partial removal of water and lights, is split into a &egr;-caprolactam stream and a heavies stream containing heavies and &egr;-caprolactam and the heavies stream is recycled to a cyclisation reactor.

Abstract: Process for the preparation of &egr;-caprolactam comprising treating 6-aminocaproic acid, 6-aminocaproate ester, 6-aminocaproamide, oligomers or polymers of these compounds or mixtures comprising at least two of these compounds in a cyclization reactor in the presence of superheated steam in which a gaseous product stream comprising &egr;-caprolactam, lights and heavies is obtained, wherein the product stream, after condensation and at least partial removal of water and lights, is split into a &egr;-caprolactam stream and a heavies stream containing heavies and &egr;-caprolactam and the heavies stream is recycled to a cyclization reactor.

Abstract: The invention relates to a process for the purification of crude &egr;-caprolactam, wherein crude &egr;-caprolactam prepared by cyclization of alkyl 6-aminocaproate, 6-aminocapronitrile, 6-aminocaproic acid, 6-aminocaproic amide and/or oligomers thereof, is subjected to a crystallization process.

Abstract: Process for the preparation of .epsilon.-caprolactam starting from an aldehyde compound comprising at least one member from among 5-formylvaleric acid, ester or amide in which the aldehyde compound is allowed to react in the presence of ammonia and hydrogen and a subsequent cyclization of the reaction products thus formed (.epsilon.-caprolactam-precursors) to .epsilon.-caprolactam is performed in the presence of water, involved the combination of steps(a) contacting the 5-formylvaleric acid, ester or amide with ammonia and water under non-hydrogenation conditions,(b) contacting the resulting mixture of step (a) with hydrogen in the presence of ammonia under hydrogenation conditions, wherein the water content is greater than 10 wt. %,(c) heating the resulting mixture of step (b) at a temperature between 200.degree. and 350.degree. C. in order to convert the reaction products of step (b) to .epsilon.-caprolactam.

Abstract: A process for the preparation of .epsilon.-caprolactam and .epsilon.-caprolactam precursors, starting from the corresponding 5-formylvalerate ester, ammonia and hydrogen in the presence of a hydrogenation catalyst is disclosed, wherein in a step (a) 5-formylvalerate ester is reacted with ammonia under non-hydrogenating conditions, and in a step (b) the reaction product obtained in step (a) is converted to .epsilon.-caprolactam and the .epsilon.-caprolactam precursor(s) under hydrogenating conditions, in the presence of ammonia.

Abstract: Method for the preparation of an aldehyde in a process in which cobalt is being recycled by:(a) hydroformylating of an ethylenically unsaturated compound with carbon monoxide and hydrogen at a pressure higher than 5 MPa and a temperature higher than 80.degree. C. in the presence of a cobalt carbonyl compound in an organic phase, following which(b) removing cobalt from the organic phase by contacting the organic phase with a polar mixture, which mixture is substantially immiscible with the organic phase, first the pressure being reduced to a pressure lower than 5 MPa and simultaneously or afterwards cooling being applied down to a temperature below 80.degree. C.

Abstract: A process is described for the preparation of a pentenoate ester by carbonylation of butadiene or butadiene derivate in the presence of carbon monoxide, a alcohol and a catalyst system comprising palladium, an carboxylic acid and a phosphine ligand, wherein the carboxylic acid is pentenoic acid.

Abstract: Process the recovering caprolactam from the residue remaining following the distillation, under reduced pressure, of impure caprolactam obtained by rearrangement of cyclohexanone oxime with sulphuric acid or oleum, by distilling the residue under reduced pressure whereby a caprolactam-containing distillate is obtained; hydrogenating the caprolactam containing distillate in an aqueous medium to obtain a hydrogenation product; and recovering caprolactam from the resulting hydrogenation product.

Abstract: A process is provided for recovering epsilon-caprolactam of a purity in excess of 99.9 wt. %, in a two-stage distillation operation. Each stage comprises an evaporator and a rectification column having a pressure drop across the theoretical trays thereof of less than about 2.5 MBAR.

Abstract: An improved process is described for the reduction of ammonium ions, while avoiding any increase in nitrate ion concentration, in a liquid stream recycled between a zone of synthesis of hydroxyl ammonium salt and a zone for synthesis of oxime, wherein the liquid stream is contacted with a gas stream consisting essentially of nitrogen monoxide and containing nitrogen dioxide at a pressure above 1 atmosphere, at a temperature of at least 80.degree. C., such that after the contact the molar NO.sub.2 /NO ratio of the gas stream is within the range of between about 10.sup.-1 to 10.sup.-4 :1.