Reclaiming .epsilon.-caprolactam from nylon 6 carpet
AssigneeBASF SE
InventorsThomas F. Corbin, Edward A. Davis, Jack A. Dellinger
Life of this patent
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Abstract
A process for the continuous recovery of .epsilon.-caprolactam provides a carpet made from nylon 6 fibers and having a backing to a separator to prepare scrap containing nylon 6 and waste. The scrap from the separator is fed to a depolymerizing reactor where the scrap is subjected to a depolymerization catalyst, temperatures of at least the melting point of nylon 6 and superheated steam to produce an .epsilon.-caprolactam containing distillate and more waste. The .epsilon.-caprolactam in the distillate is separated from other volatiles therein; and purified.
Claims9
A process for the recovery of .epsilon.-caprolactam from nylon 6 carpet, comprising:
- a) providing a carpet made from nylon 6 fibers and having a non-nylon 6 backing containing one or more non-nylon 6 materials of polypropylene, jute, latex and fillers to a mechanical separator to prepare scrap containing both nylon 6 and non-nylon 6 backing materials, and a first waste portion;
- b) feeding the scrap from the separator to a depolymerizing reactor where the scrap is subjected to a depolymerization catalyst, temperatures of at least the melting point of nylon 6 and superheated steam to produce an .epsilon.-caprolactam containing distillate and a second waste portion;
- c) separating .epsilon.-caprolactam in the distillate from other volatiles therein;
- and
- d) purifying the .epsilon.-caprolactam obtained after separating so that the .epsilon.-caprolactam is of sufficient purity for reuse as a starting material for nylon 6 intended for use in carpet fiber.
A process for recovering .epsilon.-caprolactam from nylon 6 carpet comprising:
- a) providing a carpet made from nylon 6 fibers and having a backing containing one or more non-nylon 6 materials of polypropylene, jute, latex and fillers to a mechanical separator to prepare scrap containing both nylon 6 and non-nylon 6 backing materials, and a first waste portion;
- b) feeding the scrap from the separator to a depolymerizing reactor where the scrap is subjected to a depolymerization catalyst, temperatures of at least the melting point of nylon 6 and superheated steam to produce an .epsilon.-caprolactam containing distillate and a second waste portion;
- c) separating .epsilon.-caprolactam in the distillate from other volatiles therein;
- and
- d) purifying the .epsilon.-caprolactam obtained after separating so that the purified .epsilon.-caprolactam is suitable for use as a starting material for nylon 6 carpet fiber;
- e) routing the first and second waste portions to a power generating means as fuel for power production;
- and
- f) sending the non-aqueous volatiles to the power generating means.
A process for reclaiming .epsilon.-caprolactam from nylon 6 carpet comprising:
- a) providing a carpet tufted with nylon 6 and having a backing containing latex for recycling;
- b) feeding the carpet to a depolymerization reactor;
- c) subjecting the carpet in the depolymerization reactor to a depolymerization catalyst present at about 1% to about 10% of the carpet weight at a temperature of about 230.degree. C. and 325.degree. C. to produce volatile monomers and a first waste portion;
- d) separating the volatile monomers from the first waste portion;
- and
- e) fractionating the volatile monomers to yield .epsilon.-caprolactam and a second waste portion.
Dependencies are inferred from the claim text.