The disclosure provides a decolorization and purification method of BHET material, which includes the following steps. A first dose of activated carbon is added to preliminarily treat the BHET material. After the preliminary treatment, a first cooling crystallization process and filtration are performed to obtain BHET crystals. Afterwards, an oxidant is used to chemically react with the BHET crystals to destroy a dye or impurities, and then a second dose of activated carbon is added to adsorb a chemically reacted oxide. Next, a second cooling crystallization process, filtration, and drying are performed to obtain a finished product of BHET.

The disclosure provides a decolorization and purification method of BHET material, which includes the following steps. A first dose of activated carbon is added to preliminarily treat the BHET material. After the preliminary treatment, a first cooling crystallization process and filtration are performed to obtain BHET crystals. Afterwards, an oxidant is used to chemically react with the BHET crystals to destroy a dye or impurities, and then a second dose of activated carbon is added to adsorb a chemically reacted oxide. Next, a second cooling crystallization process, filtration, and drying are performed to obtain a finished product of BHET.

Polyester polyols made from thermoplastic polyesters are disclosed. The polyols can be made by heating a thermoplastic polyester such as virgin PET, recycled PET, or mixtures thereof, with a glycol to give a digested intermediate, which is then condensed with a dimer fatty acid to give the polyol. The invention includes a polyester polyol comprising recurring units of a glycol-digested thermoplastic polyester and a dimer fatty acid. The polyester polyol can also be made in a single step by reacting the thermoplastic polyester, glycol, and dimer acid under conditions effective to produce the polyol. High-recycle-content polyols having desirable properties and attributes for formulating polyurethane products, including aqueous polyurethane dispersions, can be made. The polyols provide a sustainable alternative to bio- or petrochemical-based polyols.

Polyester polyols made from thermoplastic polyesters are disclosed. The polyols can be made by heating a thermoplastic polyester such as virgin PET, recycled PET, or mixtures thereof, with a glycol to give a digested intermediate, which is then condensed with a dimer fatty acid to give the polyol. The invention includes a polyester polyol comprising recurring units of a glycol-digested thermoplastic polyester and a dimer fatty acid. The polyester polyol can also be made in a single step by reacting the thermoplastic polyester, glycol, and dimer acid under conditions effective to produce the polyol. High-recycle-content polyols having desirable properties and attributes for formulating polyurethane products, including aqueous polyurethane dispersions, can be made. The polyols provide a sustainable alternative to bio- or petrochemical-based polyols.

Polyester polyols made from thermoplastic polyesters are disclosed. The polyols can be made by heating a thermoplastic polyester such as virgin PET, recycled PET, or mixtures thereof, with a glycol to give a digested intermediate, which is then condensed with a dimer fatty acid to give the polyol. The invention includes a polyester polyol comprising recurring units of a glycol-digested thermoplastic polyester and a dimer fatty acid. The polyester polyol can also be made in a single step by reacting the thermoplastic polyester, glycol, and dimer acid under conditions effective to produce the polyol. High-recycle-content polyols having desirable properties and attributes for formulating polyurethane products, including aqueous polyurethane dispersions, can be made. The polyols provide a sustainable alternative to bio- or petrochemical-based polyols.

The present invention provides a process for producing a compound represented by formula (I), comprising the steps of (a) reacting a compound represented by formula (II) with dimethyl sulfate in the presence of an alkali carbonate in a aqueous ketone solvent to obtain the compound represented by formula (I) as a crystalline material, and (b) washing the crystalline material with heated water at 30 to 100° C. and then further washing with an organic solvent at 30 to 80° C.

The present invention provides a process for producing a compound represented by formula (I), comprising the steps of (a) reacting a compound represented by formula (II) with dimethyl sulfate in the presence of an alkali carbonate in a aqueous ketone solvent to obtain the compound represented by formula (I) as a crystalline material, and (b) washing the crystalline material with heated water at 30 to 100° C. and then further washing with an organic solvent at 30 to 80° C.

A method includes depolymerizing post-consumer or post-industrial recycled polyethylene terephthalate (rPET) to form bis(2-hydroxyethyl) terephthalate (BHET), and reacting at least a portion of the BHET with a catalyst to form an alcohol. The alcohol includes cyclohexanedimethanol (CHDM) or 1,4-phenylenedimethanol (PDM). Further steps of the method include polymerizing the alcohol in the presence of additional BHET to form a polyester. The polyester may include poly(cyclohexylenedimethylene terephthalate (PCT), polyethylene terephthalate glycol (PETG) copolyester, polycyclohexylene dimethylene terephthalate glycol (PCTG) copolyester, polycyclohexylene dimethylene terephthalate acid (PCTA), or a monomer having repeating units with the structure (I), wherein n is an integer having a value of at least 20.

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A method includes depolymerizing post-consumer or post-industrial recycled polyethylene terephthalate (rPET) to form bis(2-hydroxyethyl) terephthalate (BHET), and reacting at least a portion of the BHET with a catalyst to form an alcohol. The alcohol includes cyclohexanedimethanol (CHDM) or 1,4-phenylenedimethanol (PDM). Further steps of the method include polymerizing the alcohol in the presence of additional BHET to form a polyester. The polyester may include poly(cyclohexylenedimethylene terephthalate (PCT), polyethylene terephthalate glycol (PETG) copolyester, polycyclohexylene dimethylene terephthalate glycol (PCTG) copolyester, polycyclohexylene dimethylene terephthalate acid (PCTA), or a monomer having repeating units with the structure (I), wherein n is an integer having a value of at least 20.

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This invention relates to a process for preparing succinic acid and succinate ester from a succinic acid salt in fermentation broth. In the first stage of this invention, renewable carbon resources are utilized to produce succinic acid through biological fermentation. The succinic acid salt in the fermentation process is subjected to double displacement reaction with a strong acid leading to release of succinic acid. Succinic acid is recovered by fractional crystallization integrated with simulated moving bed chromatography to produce succinic acid and succinate ester.