PROCESS FOR THE PREPARATION OF epsilon -CAPROLACTAM

摘要

Process for the preparation of epsilon -caprolactam, in which in a step (a) a compound with general formula (1): O=CH-(CH2)4-C(O)-R, in which R is -OH, -NH2 or O-R', in which R' is an organic group with 1 to 10 carbon atoms, is contacted with ammonia and hydrogen in a suitable solvent at elevated pressure in the presence of a hydrogenation catalyst to a mixture of primary amino compounds and epsilon -caprolactam, followed by a separate second step (b) in which the primary amino compounds are reacted to epsilon -caprolactam, wherein the solvent in step (a) is an aqueous medium, including water, the yield to epsilon -caprolactam in step (a) is more than 10 %, calculated on the initial molar amount of the compound according to formula (1), that epsilon -caprolactam is separated from the aqueous mixture obtained in step (a) by extraction and that the aqueous mixture resulting from the extraction, containing the primary amino compounds, is used in step (b).