Separation of polyolefins from nylons
AssigneeChemical Products Corporation
InventorsLloyd Ballard Mauldin, Jerry Allen Cook
Life of this patent
Estimating the term…
Abstract
In the recycling of Nylon 6 and Nylon 6,6 polyamides from post-consumer or post-industrial waste, a process is disclosed to separate Nylon 6 and Nylon 6,6 polyamides from commingled polyolefin waste components, particularly polypropylene, by admixing the waste with an ester solvent composition and heating the admixture to a temperature above the melting temperature of the contained polyolefins to form an ester solvent composition further containing dissolved polyamide polymer and a separate immiscible liquid polyolefin phase. The ester solvent composition preferably contains ethylene carbonate, propylene carbonate, butylene carbonate, or mixtures thereof.
Claims40
A method for separating a polyolefin component from a polyamide component of a post-consumer or post-industrial commingled waste containing both polyolefin and polyamide polymeric components comprising:
- (a) admixing the commingled waste with an ester solvent composition, wherein the polyolefin is immiscible in the ester solvent composition;
- (b) heating the admixture to a temperature above the melting temperature of the polyolefin component sufficient to dissolve at least a portion of the polyamide component of the commingled waste in the ester solvent composition and form a separate immiscible molten polyolefin phase;
- (c) separating the ester solvent composition containing dissolved polyamide from the immiscible polyolefin phase.
A method for separating the Nylon 6 polymer component from the polyolefin polymer component of commingled post-consumer carpet waste containing at least polyolefin and Nylon 6 polyamide fibers comprising:
- (a) admixing the commingled carpet waste with an ester solvent composition containing at least one cyclic ester;
- (b) heating the admixture to a temperature above about 190 degrees Celsius for a period of at least about 5 minutes to dissolve at least a portion of the Nylon 6 fibers in the ester solvent composition and form a separate discrete molten polyolefin phase;
- and (c) separating the discrete molten polyolefin phase from the ester solvent composition phase by skimming, filtration, centrifugation, or combinations thereof.
A method for separating a Nylon 6,6 polyamide polymer component from a polyolefin polymer component of commingled post-consumer carpet waste containing at least polyolefin and Nylon 6,6 fibers comprising:
- (a) admixing the commingled carpet waste with an ester solvent composition containing at least one cyclic ester;
- (b) heating the admixture to a temperature above about 215 degrees Celsius for a period of at least about 5 minutes to dissolve at least a portion of the Nylon 6,6 fibers in the ester solvent composition and form a separate discrete molten polyolefin phase;
- and (c) separating the discrete molten polyolefin phase from the ester solvent composition phase by skimming, filtration, centrifugation, or combinations thereof.
A method for separating a polyolefin component from a nylon component of a commingled polymer composition comprising:
- (a) admixing the commingled polymer composition with an ester solvent composition comprising at least one cyclic ester, wherein the polyolefin is immiscible in the ester solvent composition;
- (b) heating the admixture to a temperature above the melting temperature of the polyolefin component sufficient to dissolve at least a portion of the nylon component of the commingled polymer composition in the ester solvent composition and to form a separate immiscible molten polyolefin phase;
- and
- (c) separating the ester solvent composition containing dissolved nylon from the immiscible polyolefin phase.
A method for separating a Nylon 6 polymer component from a polyolefin polymer component of commingled polymer composition comprising:
- (a) admixing the commingled polymer composition with a carbonate ester solvent composition;
- (b) heating the admixture to a temperature above about 190 degrees Celsius to dissolve at least a portion of the Nylon 6 polymer component in the carbonate ester solvent composition and form a separate discrete molten polyolefin phase;
- and
- (c) separating the discrete molten polyolefin phase from the carbonate ester solvent composition phase.
A method for separating a Nylon 6,6 polyamide component from a polyolefin polymer component of commingled polymer composition comprising:
- (a) admixing the commingled polymer composition with a carbonate ester solvent composition to form an admixture;
- (b) heating the admixture to a temperature above about 215 degrees Celsius to dissolve at least a portion of the Nylon 6,6 fibers in the carbonate ester solvent composition and to form a separate discrete molten polyolefin phase;
- and
- (c) separating the discrete molten polyolefin phase from the carbonate ester solvent composition.
Dependencies are inferred from the claim text.