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.

An esterification reaction apparatus and an esterification reaction method, the esterification reaction apparatus comprising a reaction tank having an accommodation part, in which a raw material containing carboxylic acid and alcohol is accommodated, a heating unit configured to individually heat partition regions that are partitioned into N regions in a vertical direction of the accommodation part, and a controller configured to control the heating unit so that only the partition regions in which a liquid is accommodated among the N partition regions are heated, thereby performing an esterification reaction of the raw material.

An esterification reaction apparatus and an esterification reaction method, the esterification reaction apparatus comprising a reaction tank having an accommodation part, in which a raw material containing carboxylic acid and alcohol is accommodated, a heating unit configured to individually heat partition regions that are partitioned into N regions in a vertical direction of the accommodation part, and a controller configured to control the heating unit so that only the partition regions in which a liquid is accommodated among the N partition regions are heated, thereby performing an esterification reaction of the raw material.

Provided is a method of preparing a diester-based material, more particularly, a method of preparing a diester-based material, which is carried out by a continuous preparation process of a diester-based material including a reaction part in which a total of n reaction units from a first reaction unit to an nth reaction unit are connected in series, the reaction unit including a reactor which esterifies dicarboxylic acid and alcohol, including: esterifying dicarboxylic acid and alcohol in a reactor of the first reaction unit to produce a reaction product, and supplying a lower discharge stream including the reaction product to a reaction unit at a rear end through a lower discharge line; and supplying a liquid material through a liquid supply line connected to a lower discharge line of the reactor of the first reaction unit.

Provided is a method of preparing a diester-based material, more particularly, a method of preparing a diester-based material, which is carried out by a continuous preparation process of a diester-based material including a reaction part in which a total of n reaction units from a first reaction unit to an nth reaction unit are connected in series, the reaction unit including a reactor which esterifies dicarboxylic acid and alcohol, including: esterifying dicarboxylic acid and alcohol in a reactor of the first reaction unit to produce a reaction product, and supplying a lower discharge stream including the reaction product to a reaction unit at a rear end through a lower discharge line; and supplying a liquid material through a liquid supply line connected to a lower discharge line of the reactor of the first reaction unit.

Provided is a method of preparing a diester-based material, more particularly, a method of preparing a diester-based material, which is carried out by a continuous preparation process of a diester-based material including a reaction part in which a total of n reaction units from a first reaction unit to an nth reaction unit are connected in series, the reaction unit including a reactor which esterifies dicarboxylic acid and alcohol, including: esterifying dicarboxylic acid and alcohol in a reactor of the first reaction unit to produce a reaction product, and supplying a lower discharge stream including the reaction product to a reaction unit at a rear end through a lower discharge line; and supplying a liquid material through a liquid supply line connected to a lower discharge line of the reactor of the first reaction unit.

The present invention relates to a method of manufacturing a diester-based compound, and, more particularly, to a method of manufacturing a diester-based compound, which is performed using a continuous process including a reaction part in which a total of n reaction units spanning from a first reaction unit to an nth reaction unit are connected in series, wherein each of the reaction units includes a reactor, and the method includes: supplying a feed stream including a dicarboxylic acid and an alcohol into the first reactor; esterifying the feed stream to prepare a reaction product; and supplying a lower discharge stream including the reaction product into the reactor of the rear reaction unit. In this case, a conversion rate of the esterification reaction in the first reactor is controlled in a range of 50 to 80%.

The present invention relates to a method of manufacturing a diester-based compound, and, more particularly, to a method of manufacturing a diester-based compound, which is performed using a continuous process including a reaction part in which a total of n reaction units spanning from a first reaction unit to an nth reaction unit are connected in series, wherein each of the reaction units includes a reactor, and the method includes: supplying a feed stream including a dicarboxylic acid and an alcohol into the first reactor; esterifying the feed stream to prepare a reaction product; and supplying a lower discharge stream including the reaction product into the reactor of the rear reaction unit. In this case, a conversion rate of the esterification reaction in the first reactor is controlled in a range of 50 to 80%.

The present invention relates to a method of manufacturing a diester-based compound, and, more particularly, to a method of manufacturing a diester-based compound, which is performed using a continuous process including a reaction part in which a total of n reaction units spanning from a first reaction unit to an nth reaction unit are connected in series, wherein each of the reaction units includes a reactor, and the method includes: supplying a feed stream including a dicarboxylic acid and an alcohol into the first reactor; esterifying the feed stream to prepare a reaction product; and supplying a lower discharge stream including the reaction product into the reactor of the rear reaction unit. In this case, a conversion rate of the esterification reaction in the first reactor is controlled in a range of 50 to 80%.