Process for the synthesis of epsilon-caprolactam
AssigneeMontedipe S.p.A.
InventorsFrancesco Cellini, Vittorio Gervasutti, Raffaele Tancorra, Sergio Tonti
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Abstract
The invention concerns a two-step process for the synthesis of caprolactam by reaction of cylcohexanone-oxime with an excess of oleum, carried out in a first step with only a portion of the oxime and in the presence of liquid SO.sub.2, according to usual "cold" techniques, the amount of free SO.sub.3 in the oleum being equal to or greater than 50% by weight, wherein said "cold" step is completed by a second "hot" step, by adding a second portion of oxime, the ratio between said second portion and said first portion ranging from 0.5 to 1.2.
Claims6
A process for the synthesis of caprolactam by reaction of cyclohexanone-oxime with an excess of oleum, achieved in a first step with a first portion of oxime and in the presence of liquid SO.sub.2, according to the usual "cold" technique, where the amount of free SO.sub.3 in the oleum is equal to or greater than 50% b.w., characterized in that the "cold" step is completed by a second "hot" step, by adding a second portion of oxime, and in that the ratio between said second portion and said first portion of oxime ranges from 0.5 to 1.2.
Dependencies are inferred from the claim text.