Provided is a method of efficiently removing an ink layer. The method of removing an ink layer from a shrink sleeve label includes preheating the shrink sleeve label including the ink layer, shredding the shrink sleeve label after the preheating to fabricate shrink sleeve label pieces , and removing the ink layer from the shrink sleeve label pieces by alkaline desorption. A temperature of the preheating is the same as a temperature of the alkaline desorption or higher than the temperature of the alkaline desorption.

Provided is a method of efficiently removing an ink layer. The method of removing an ink layer from a shrink sleeve label includes preheating the shrink sleeve label including the ink layer, shredding the shrink sleeve label after the preheating to fabricate shrink sleeve label pieces , and removing the ink layer from the shrink sleeve label pieces by alkaline desorption. A temperature of the preheating is the same as a temperature of the alkaline desorption or higher than the temperature of the alkaline desorption.

Disclosed herein is a process to convert PVC plastic into a dechlorinated polymer, such as high density polyethylene, while substantially avoiding carbonization. The process also facilitates Cl recovery and/or reintroducing the dechlorinated plastic into product streams. In some embodiments, the process comprises heating a mixture of PVC and a catalyst and/or a base in a solvent, optionally in the presence of hydrogen gas.

A process for recycling lignocellulosic fibers from a fiberboard (100) comprising compressed lignocellulosic fibers bonded together by a binding agent. The process comprises the steps of: —disintegrating (101) the fiberboard (100) to provide fiberboard pieces (110); —steaming (111) the fiberboard pieces (110) to decompress and release the lignocellulosic fibers by hydrating them, as well as hydrolyzing the binding agent; —releasing the overpressure; —removing excess water vapor to provide portions (120) comprising released lignocellulosic fibers; and—separating (121) the lignocellulosic fibers in the portions (120) comprising released lignocellulosic fibers to provide recycled lignocellulosic fibers (130).

A process for recycling lignocellulosic fibers from a fiberboard (100) comprising compressed lignocellulosic fibers bonded together by a binding agent. The process comprises the steps of: —disintegrating (101) the fiberboard (100) to provide fiberboard pieces (110); —steaming (111) the fiberboard pieces (110) to decompress and release the lignocellulosic fibers by hydrating them, as well as hydrolyzing the binding agent; —releasing the overpressure; —removing excess water vapor to provide portions (120) comprising released lignocellulosic fibers; and—separating (121) the lignocellulosic fibers in the portions (120) comprising released lignocellulosic fibers to provide recycled lignocellulosic fibers (130).

The present disclosure provides methods and processes for the recovery of compounds (e.g., pendant groups) from polymeric materials, as well as methods for recycling and reusing such compounds by synthetically converting a recovered compound to building blocks that can be used in, e.g., curable resins for the fabrication of new devices, such as medical devices (e.g., orthodontic appliances).

Described herein are systems and methods for the depolymerization of polyethylene-based plastics. In one embodiment, a method is disclosed that comprises combining a polyethylene-based plastic with a solvent in a reactor to generate a plastic solvent mixture, heating the plastic solvent mixture in the reactor, and fractionating the plastic solvent mixture into a gas phase product, a solid phase product, and a liquid phase product. In another embodiment, a system is disclosed that comprises a solvent, and a reactor configured to receive the polyethylene-based plastic and the solvent and convert the polyethylene-based plastic into a gas phase product, a solid phase product, and a liquid phase product, the reactor being configured to operate at a temperature greater than 275° C. and at a pressure greater than 2 megapascals.

The present disclosure relates to a method for upgrading liquefied waste plastics, the method including a step (A) of providing liquefied waste plastics (LWP) material, a step (B) including pre-treating the liquefied waste plastics material by contacting the liquefied waste plastics material with an aqueous medium having a pH of at least 7 at a temperature of 200° C. or more, followed by liquid-liquid separation, to produce a pre-treated liquefied waste plastics material, a step (C) including hydrotreating the pre-treated liquefied waste plastics material, optionally in combination with a co-feed, to obtain a hydrotreated material, and a step (D) of post-treating the hydrotreated material to obtain a steam cracker feed.

The present disclosure relates to a method for upgrading liquefied waste plastics, the method including a step (A) of providing liquefied waste plastics (LWP) material, a step (B) including pre-treating the liquefied waste plastics material by contacting the liquefied waste plastics material with an aqueous medium having a pH of at least 7 at a temperature of 200° C. or more, followed by liquid-liquid separation, to produce a pre-treated liquefied waste plastics material, a step (C) including hydrotreating the pre-treated liquefied waste plastics material, optionally in combination with a co-feed, to obtain a hydrotreated material, and a step (D) of post-treating the hydrotreated material to obtain a steam cracker feed.

Pre-treatment methods for polyolefin-based feed streams before depolymerization are described. Polyolefins are separated from other material in the polyolefin-based feed stream using density differences in an aqueous solution, which allows for a pre-treatment method that does not affect the depolymerization catalyst. By removing the non-polyolefin materials from the feed stream, the depolymerization of the polyolefin material can proceed at lower temperatures for longer cycles. This results in a more efficient process with a smaller carbon footprint.