Provided are methods for depolymerizing polyesters, e.g., PET, PBT, and PEN. In embodiments, a method for depolymerizing a polyester comprises combining a polyester comprising a plurality of ester linking groups (R′C(O)OR), a metal triflate catalyst, and a hydrogenation catalyst, under conditions to cleave a C—O bond in an alkoxy group (OR) of an ester linking group of the plurality of ester linking groups.

The invention relates to the field of road construction materials, and it is intended to improve the quality of road surfaces, roofing and insulating materials based on bitumens, which is achieved by improving the quality of bitumens with the help of using modified crumb rubber—a disposal product of used automotive and tractor tires, in particular, the invention relates to a low-temperature method for manufacturing modified crumb rubber to improve the quality of bitumens and asphalt concretes and to the technology for mixing it with bitumen, for the purpose of creating a uniform material that is not prone to destruction during long-term storage. The present invention consists in the development of a new method for manufacturing the modified crumb rubber, comprising preparing a mix from the following components: crumb rubber from used automotive and tractor tires with a particle size of up to 1 mm—50-65 wt. %, oxides and/or hydroxides of alkaline-earth metals—10-20 wt. %, petroleum oil of solvent refining with the viscosity of from 0.05 to 1.5 Pa*s at 60° C.—20-30 wt. %, an amine type antiageing agent—a heterocyclic nitrogen-containing compound—0.1-2.0 wt. %; mixing the components of the resulting mix with a shock-shear load on the material in a mixer-activator at a temperature of 80-120° C.; and further cooling the resulting mix to a room temperature.

Industrial fermentation for the production of lactic acid from organic waste combined with chemical recycling of polylactic acid are provided, to obtain lactic acid at high yields.

Industrial fermentation for the production of lactic acid from organic waste combined with chemical recycling of polylactic acid are provided, to obtain lactic acid at high yields.

Systems and methods for recycling polymers are provided. One embodiment provides a method for recycling synthetic polymers by combining the polymers with a solid depolymerizing catalyst in a vessel, mechanically shearing the combined polymers and the solid depolymerizing catalyst against each other to produce monomers from the polymers; and collecting the monomers. In some embodiments the solid depolymerizing catalyst is solid sodium hydroxide. In some embodiments collecting the monomers is achieved by contacting the sheared polymer and catalyst with a recyclable volatile solvent to dissolve the monomers. In some embodiments, the method includes purifying the collected monomers for repolymerization. In some embodiments purifying the monomers is achieved using nanofiltration membrane technology, cyclic fixed bed adsorption, simulated moving-bed adsorption or a combination thereof.

Systems and methods for recycling polymers are provided. One embodiment provides a method for recycling synthetic polymers by combining the polymers with a solid depolymerizing catalyst in a vessel, mechanically shearing the combined polymers and the solid depolymerizing catalyst against each other to produce monomers from the polymers; and collecting the monomers. In some embodiments the solid depolymerizing catalyst is solid sodium hydroxide. In some embodiments collecting the monomers is achieved by contacting the sheared polymer and catalyst with a recyclable volatile solvent to dissolve the monomers. In some embodiments, the method includes purifying the collected monomers for repolymerization. In some embodiments purifying the monomers is achieved using nanofiltration membrane technology, cyclic fixed bed adsorption, simulated moving-bed adsorption or a combination thereof.

The present invention relates to a method for production of terephthalic acid using high polymerization degree polyethylene terephthalate, which includes: (i) introducing high polymerization degree polyethylene terephthalate having an intrinsic viscosity of 0.75 dl/g or more into a continuous reactor, and then heating and pressurizing the same to prepare a fluidal polyethylene terephthalate; (ii) introducing a mixed slurry prepared by mixing an alkaline material containing an alkali-metal, a weak acid salt of the alkali-metal and ethylene glycol together into an internal position of the continuous reactor, through which the fluidal polyethylene terephthalate passes, and implementing neat reaction of the fluidal polyethylene terephthalate with the mixed slurry in the continuous reactor to prepare alkali-metal terephthalate; and (iii) dissolving the prepared alkali-metal terephthalate in water, removing foreign substances through filtration and centrifugation, adding acid to the alkali-metal terephthalate dissolved in water and reacting the same, thereby producing terephthalic acid.

The present invention relates to a method for production of terephthalic acid using high polymerization degree polyethylene terephthalate, which includes: (i) introducing high polymerization degree polyethylene terephthalate having an intrinsic viscosity of 0.75 dl/g or more into a continuous reactor, and then heating and pressurizing the same to prepare a fluidal polyethylene terephthalate; (ii) introducing a mixed slurry prepared by mixing an alkaline material containing an alkali-metal, a weak acid salt of the alkali-metal and ethylene glycol together into an internal position of the continuous reactor, through which the fluidal polyethylene terephthalate passes, and implementing neat reaction of the fluidal polyethylene terephthalate with the mixed slurry in the continuous reactor to prepare alkali-metal terephthalate; and (iii) dissolving the prepared alkali-metal terephthalate in water, removing foreign substances through filtration and centrifugation, adding acid to the alkali-metal terephthalate dissolved in water and reacting the same, thereby producing terephthalic acid.

The present invention relates to a multilayer, coextruded polyester film that includes at least one outer layer (A) and a base layer (B), in which the at least one outer layer (A) includes to an extent of at least 60 wt % of a copolyester that includes units derived from dicarboxylic acids and diols, in which the units derived from dicarboxylic acids include at least 65 mol % of units derived from terephthalic acid and at least 5 mol % of units derived from 5-sulfo-isophthalic acid and the units derived from diols include at least 90 mol % of units derived from ethylene glycol.

The present invention further relates to a process for producing the film according to the invention, to the use thereof and to a process for recycling the polyester film according to the invention.

The present invention relates to a multilayer, coextruded polyester film that includes at least one outer layer (A) and a base layer (B), in which the at least one outer layer (A) includes to an extent of at least 60 wt % of a copolyester that includes units derived from dicarboxylic acids and diols, in which the units derived from dicarboxylic acids include at least 65 mol % of units derived from terephthalic acid and at least 5 mol % of units derived from 5-sulfo-isophthalic acid and the units derived from diols include at least 90 mol % of units derived from ethylene glycol.

The present invention further relates to a process for producing the film according to the invention, to the use thereof and to a process for recycling the polyester film according to the invention.