Method for recycling plastic film
AssigneeSortology Ltd
InventorJames Donaldson
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Abstract
This invention relates to a method for recycling plastics, e.g. plastic films.
Claims20
A method of recycling plastic film, the method comprising:
- a) exposing pieces of plastic film to an aqueous deinking solution comprising a surfactant and a base to produce pieces of deinked plastic film;
- b) recovering the pieces of deinked plastic film from the deinking solution;
- and
- c) sorting the deinked plastic film into a plurality of product classes.
The method of any preceding claim, wherein the sorting of deinked plastic film in step c) comprises sorting the deinked plastic film according to the base material of the plastic film.
The method of any preceding claim, wherein the sorting of deinked plastic film in step c) comprises sorting the deinked plastic film according to the level of deinking that has occurred in step a).
The method of any preceding claim, wherein the surfactant is a trialkyl hydroxyalkyl ammonium salt.
The method of any preceding claim, wherein the surfactant has a structure according to formula (II):
- wherein R1 is C12-C14 alkyl.
The method of any preceding claim, wherein the surfactant is present in the deinking solution in an amount of from 0.025 wt % to 2 wt %.
The method of any preceding claim, wherein the base is an inorganic base selected from LiOH, NaOH, KOH, Na2CO3, NaHCO3, K2CO3, and KHCO3;
The method of any preceding claim, wherein the base is NaOH.
The method of any preceding claim, wherein the base is present in the deinking solution in an amount of from 0.5 wt % to 10 wt %.
The method of any preceding claim, wherein the deinking solution further comprises an anionic detergent booster.
The method of any preceding claim, wherein the anionic detergent booster is selected from sodium lauryl sulfate (SLS), sodium lauryl ether sulfate (SLES), ammonium lauryl sulfate (ALS), and combinations thereof.
The method of any preceding claim, wherein the anionic detergent booster is present in an amount of from 0.1 to 2 wt %.
The method of any preceding claim, wherein the plastic film is selected from a polypropylene (PP), polyethylene (PE), and a low-density polyethylene (LDPE) film.
The method of any preceding claim, further comprising the step of isolating one or more product class from step c) and independently extruding the pieces of deinked plastic film in that product class to form a recycled plastic product.
Dependencies are inferred from the claim text.