Organic compounds -- part of the class 532-570 series – Organic compounds – Unsubstituted hydrocarbyl chain between the ring and the -c-...
Patent
1997-04-18
1999-02-09
Shah, Mukund J.
Organic compounds -- part of the class 532-570 series
Organic compounds
Unsubstituted hydrocarbyl chain between the ring and the -c-...
528323, C07D20112
Patent
active
058696547
ABSTRACT:
The present invention provides an improved process for the recovery of caprolactam from polycaprolactam processing waste. The present process for depolymerizing polycaprolactam waste to form caprolactam comprises the step of: in the absence of added catalyst, contacting the polycaprolactam waste with superheated steam at a temperature of about 250.degree. C. to about 400.degree. C. and at a pressure within the range of about 1.5 atm to about 100 atm and substantially less than the saturated vapor pressure of water at the temperature wherein a caprolactam-containing vapor stream is formed.
The formed caprolactam may then be used in the production of engineered resins and fibers.
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Levy Alan Bart
Sifniades Stylianos
Allied-Signal Inc.
Andrews Virginia S.
Brown Melanie L.
Rao Deepak R.
Shah Mukund J.
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