Abstract: The invention relates to a solid composition comprising at least 90.0 wt. % bis(2-hydroxyethyl) terephthalate (BHET), as based on dry weight and having a pore volume in the range of 0.20 to 1.0 cm3/g. The porosity is above 25% or even above 35%. The solid composition is made by crystallisation, followed by granulation and fluid bed drying.

Abstract: A method and reactor system for depolymerizing a polymer is described. The method comprises the steps of providing the polymer and a solvent in a reactor to obtain a reaction mixture, the solvent being capable of reacting with the polymer to degrade the polymer into at least repeating units; providing a reusable catalyst in the reaction mixture being capable of catalyzing said degradation; degrading the polymer in the reaction mixture at degradation reaction conditions to obtain a depolymerized mixture comprising at least light oligomers having from 2 to 4 repeating units inclusively; removing unreacted polymer, solid particles and optionally very heavy oligomers from the depolymerized mixture after exiting the reactor; recovering at least a part of the reusable catalyst from the depolymerized mixture; and recovering the light oligomers from the depolymerized mixture. During recovery of the reusable catalyst, the depolymerized mixture comprises heavy oligomers having at least 5 repeating units.

Abstract: A continuous method for depolymerizing polycaprolactam waste into caprolactam is described. In the method, a melt of the polycaprolactam waste and an inert gas are fed to a reactor in a continuous manner. Water and an aromatic hydrocarbon are also fed to the reactor and the polycaprolactam waste is contacted with superheated steam of the water/hydrocarbon mixture at a temperature of between 260° C. and 300° C. and at a gauge pressure from 1 barg to 70 barg. Turbulent mixing conditions are created in the reactor, and a caprolactam-containing vapor stream is created in the reactor which exits the reactor at an outlet. The caprolactam is separated from the exited caprolactam-containing vapor stream by partial condensation, and collected. A reactor system for carrying out the method is also described.

Abstract: The invention relates to a method of separating a first contaminant from a feed stream further comprising a condensation polymer. The invention further relates to a reactor system for carrying out the method, comprising at least one depolymerization vessel, configured for depolymerizing a condensation polymer into monomer, dimer, trimer and/or oligomer, which depolymerizing occurs in an alcoholic solvent, wherein said condensation polymer is provided as a feed stream further comprising a first contaminant, the reactor system comprising a separation stage, said separation stage comprising a separation vessel, downstream of the depolymerization vessel, configured for collecting a first contaminant, wherein said first contaminant is separated from the alcoholic solvent on the basis of a density separation so that the first contaminant is arranged on top of the alcoholic solvent.

Abstract: The reactor system comprises a reactor vessel with at least one inlet and a first and a second outlet, which reactor vessel is configured for depolymerisation of a condensation polymer and which first and second outlet are configured for removal of a first and a second part of a reaction mixture. The reactor system further comprises a heat exchanger downstream of the first outlet. Herein the second outlet is arranged at a lower position of the reactor vessel than the first outlet. The first outlet is configured for removal of the first part being a dispersion and/or solution comprising said condensation polymer and depolymerisation products thereof in a solvent. Said first part is led to the heat exchanger. The second outlet is configured for removal of the second part including agglomerates. The reactor system is used for depolymerisation of a condensation polymer.

Abstract: The invention relates to a solid composition comprising at least 90.0 wt. % bis(2-hydroxyethyl) terephthalate (BHET), as based on dry weight and having a pore volume in the range of 0.20 to 1.0 cm3/g. The porosity is above 25% or even above 35%. The solid composition is made by crystallisation, followed by granulation and fluid bed drying.