Integrated manufacturing of REciclable multi-material COmposites for the TRANSport sector
PROCESS FOR DEPOLYMERIZATION OF POLYALKYLENE TEREPHTHALATES IN AN EXTRUDER
The invention relates to an improved process for depolymerization of at least one polymer P1 which is a polyalkylene terephthalate, i.e. a polymer comprising terephthalic acid units and alkylene glycol units, in particular polyethylene terephthalate PET or polybutylene terephthalate PBT. The process is particularly suitable for depolymerization and for recycling of PET-containing wastes. The process is performed in an extruder E having at least two barrels G1, G2, wherein the at least one polymer P1 is provided in barrel G1 as suspension S1. The suspension S1 is then transported into the barrel G2 and there at least one glycol compound G, preferably ethylene glycol, is added to the suspension S1. The at least one glycol compound G reacts in the suspension S1 with the at least one polymer P1 to afford a mixture MG2 comprising the corresponding cleavage products P2. The resulting mixture MG2 is transported to the product outlet EX of the extruder E. At the product outlet EX a portion of MG2 is withdrawn and utilized as the continuous phase PKon of the suspension S1 provided in G1. The process allows for a safer process mode since it avoids the uncontrolled increase in temperature and pressure during depolymerization of the polymer P1.
» Number: WO2024156567A1 (A1)
» Publication Date: 02/08/2024
» Applicant: EVONIK OPERATIONS GMBHâ??[DE]
» Inventor: ROETTGER DIRKâ??[DE]; ZANDER CHRISTIANâ??[DE] (3)
This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement Nº 768737
