C08J11/24

OPTIMIZED DEPOLYMERIZATION PROCESS BY GLYCOLYSIS OF A POLYESTER COMPRISING POLYETHYLENE TEREPHTHALTE

The invention relates to a process of depolymerization of a polyester feedstock comprising PET, which comprises: a) a conditioning step; b) a glycolysis step in the presence of diol; c) a step of separation of the diol, producing at least a gaseous diol effluent, at least a liquid diol effluent and a liquid monomers effluent; g) a step of separating said liquid monomers effluent into a heavy impurities effluent and a prepurified monomers effluent, this step being conducted with a residence time of less than 10 min; e) a step of decolourizing the prepurified monomers effluent, in the presence of at least one adsorbent, and f) a diol purification step, which is supplied with at least a gaseous diol effluent and at least a liquid diol effluent, which are obtained from step c), and which produces a purified diol effluent and one or more impurities effluent(s).

OPTIMIZED DEPOLYMERIZATION PROCESS BY GLYCOLYSIS OF A POLYESTER COMPRISING POLYETHYLENE TEREPHTHALTE

The invention relates to a process of depolymerization of a polyester feedstock comprising PET, which comprises: a) a conditioning step; b) a glycolysis step in the presence of diol; c) a step of separation of the diol, producing at least a gaseous diol effluent, at least a liquid diol effluent and a liquid monomers effluent; g) a step of separating said liquid monomers effluent into a heavy impurities effluent and a prepurified monomers effluent, this step being conducted with a residence time of less than 10 min; e) a step of decolourizing the prepurified monomers effluent, in the presence of at least one adsorbent, and f) a diol purification step, which is supplied with at least a gaseous diol effluent and at least a liquid diol effluent, which are obtained from step c), and which produces a purified diol effluent and one or more impurities effluent(s).

Process for recovering and reusing depolymerization catalyst

The present disclosure relates to the recovery of an alkoxide catalyst used in a process depolymerizing a polyester to form a diacid or diester and a diol. The present disclosure also relates to the recovery of an alkoxide catalyst used in a process depolymerizing polyethylene terephthalate to form dimethyl terephthalate and mono ethylene glycol.

Process for recovering and reusing depolymerization catalyst

The present disclosure relates to the recovery of an alkoxide catalyst used in a process depolymerizing a polyester to form a diacid or diester and a diol. The present disclosure also relates to the recovery of an alkoxide catalyst used in a process depolymerizing polyethylene terephthalate to form dimethyl terephthalate and mono ethylene glycol.

METHOD FOR OBTAINING A PURIFIED DIESTER EFFLUENT BY DEPOLYMERISING A POLYESTER COMPRISING OPAQUE POLYETHYLENE TEREPHTHALATE

The present invention relates to a process for depolymerizing a polyester feedstock comprising opaque PET, which comprises: a) a conditioning step; b) a step of glycolysis, operated at between 180 and 400° C., a residence time of from 0.1 to 10 h in the presence of diol; c) a diol separation step, at a temperature of between 100 and 250° C., a pressure lower than that of step b) and producing a diol effluent and an effluent rich in monomers; d) a step of separating into a heavy impurities effluent and a prepurified monomers effluent, at a temperature of less than 250° C. and a pressure of less than 0.001 MPa and a residence time of less than 10 min; e) a step of decolourizing the prepurified monomers effluent, by adsorption of a mixture comprising between 20% and 90% by weight of the prepurified monomers effluent and a solvent, at a temperature of between 100 and 200° C., a pressure of between 0.1 and 1.0 MPa and in the presence of at least one adsorbent.

METHOD FOR OBTAINING A PURIFIED DIESTER EFFLUENT BY DEPOLYMERISING A POLYESTER COMPRISING OPAQUE POLYETHYLENE TEREPHTHALATE

The present invention relates to a process for depolymerizing a polyester feedstock comprising opaque PET, which comprises: a) a conditioning step; b) a step of glycolysis, operated at between 180 and 400° C., a residence time of from 0.1 to 10 h in the presence of diol; c) a diol separation step, at a temperature of between 100 and 250° C., a pressure lower than that of step b) and producing a diol effluent and an effluent rich in monomers; d) a step of separating into a heavy impurities effluent and a prepurified monomers effluent, at a temperature of less than 250° C. and a pressure of less than 0.001 MPa and a residence time of less than 10 min; e) a step of decolourizing the prepurified monomers effluent, by adsorption of a mixture comprising between 20% and 90% by weight of the prepurified monomers effluent and a solvent, at a temperature of between 100 and 200° C., a pressure of between 0.1 and 1.0 MPa and in the presence of at least one adsorbent.

METHOD FOR MANUFACTURE OF POLYESTERS WITH RECYCLE CONTENT

A method for manufacture of polyesters with recycle content is described in various aspects. The methods of the present disclosure effectively and cost-efficiently incorporates recycled DMT into existing TPA-based polyester manufacturing systems. Recycle feed compositions for manufacture of polyesters with recycle content and recycled content polyesters are also described.

METHOD FOR MANUFACTURE OF POLYESTERS WITH RECYCLE CONTENT

A method for manufacture of polyesters with recycle content is described in various aspects. The methods of the present disclosure effectively and cost-efficiently incorporates recycled DMT into existing TPA-based polyester manufacturing systems. Recycle feed compositions for manufacture of polyesters with recycle content and recycled content polyesters are also described.

PROCESS FOR TREATING POLYESTER METHANOLYSIS DEPOLYMERIZATION PRODUCT STREAMS

Disclosed is a method for treating the product stream from a polyester methanolysis depolymerization process wherein the product stream includes dimethyl terephthalate and one or more side species selected from the group consisting of dimethyl phthalate, dimethyl isophthalate, bisphenol-A, an adipic acid diester and colorants. The method includes a) hydrogenating said dimethyl terephthalate to form one or more of dimethyl 1,4-cyclohexanedicarboxylate and 1,4-cyclohexanedimethanol; and (b) hydrogenating one or more of said one or more side species of said product stream. A method for depolymerization of polyester is also described.

DEPOLYMERIZATION OF RECOVERED PLASTIC MATERIALS

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.