Abstract: The present invention relates to a method for obtaining a monomer by degrading a polymer, the polymer being a homo or copolymer of the monomer, the method comprising the steps of providing the polymer and a solvent as a reaction mixture in a reactor, wherein the solvent is a reactant capable of reacting with the polymer to degrade the polymer into oligomers and at least one monomer; providing a reusable catalyst being capable of degrading the polymer into oligomers and at least one monomer; degrading the polymer in the reaction mixture at reaction conditions using the catalyst to form a monomer; and recovering the catalyst from the reaction mixture; wherein the method further comprises the addition of a base to at least one of the reaction steps. The present invention furthermore relates to the use of a base as a co-catalyst for a catalyst for degrading a polymer in a reaction mixture at reaction conditions.

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 method and reactor system for depolymerizing a terephthalate polymer into reusable raw material are described, as well as a raw material obtainable by the method. The method inter alia comprises providing the polymer and a solvent such as ethylene glycol as a reaction mixture in a reactor. A heterogeneous catalyst, such as a metal containing particle, and/or a homogeneous catalyst is provided in the reaction mixture and the reaction mixture heated to depolymerize the polymer. Monomer comprising bis-(2-hydroxyethyl)-terephthalate (BHET), and 2-hydroxyethyl[2-(2-hydroxyethoxy)ethyl]terephthalate (BHEET) as byproduct are formed. The BHET is recovered from a depolymerized product stream exiting the reactor and a BHET-depleted stream is formed. A mass fraction of BHEET in the depolymerized product stream and/or in the BHET-depleted stream is monitored and adjusted to below a predetermined limit value of the BHEET-mass fraction in the depolymerized product stream.

Abstract: A method and reactor system for depolymerizing a terephthalate polymer into reusable raw material are described, as well as a raw material obtainable by the method. The method inter alia comprises providing the polymer and a solvent such as ethylene glycol as a reaction mixture in a reactor. A reusable catalyst complex comprising a catalyst entity, a metal containing nanoparticle, and a bridging moiety connecting the catalyst entity to the metal containing nanoparticle is dispersed in the reaction mixture and the reaction mixture heated to depolymerize the polymer into monomers comprising bis-(2-hydroxyethyl)-terephthalate (BHET). 2-hydroxyethyl[2-(2-hydroxyethoxy)ethyl]terephthalate (BHEET) is formed as byproduct. The BHET is recovered from the depolymerized product stream and a BHET-depleted stream is formed.

Abstract: A method is described for the production of a polyhydric alcohol from a urethane containing polymer. The method first provides a reaction mixture comprising said polymer, a solvent, which comprises a polyol capable of reacting with said polymer to depolymerize said polymer; and a catalyst, which comprises catalyst particles. Said polymer is depolymerized in said reaction mixture by reacting with said polyol to produce said polyhydric alcohol. A further step allows said reaction mixture containing said polyhydric alcohol product to separate into an, upper, product phase containing said polyhydric alcohol and another, lower, phase mainly containing said polyol and said catalyst. The catalyst is recovered from said another phase, while said polyhydric alcohol product is recovered from said product phase.

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: A method of depolymerization of waste polymer material into monomers comprises releasing at least part of the at least one dye from the waste polymer material in an alcoholic solvent without depolymerizing the condensation polymer in the waste polymer material and at conditions preventing a reaction between the dye and the alcoholic solvent, wherein the alcoholic solvent is a polyol. The alcoholic solvent is added in a weight ratio of the alcoholic solvent to the waste polymer material of between 200:1 and 10:1. The at least partially decolorized waste polymer is then separated from the alcoholic solvent, and the at least one dye is extracted from the alcoholic solvent so as to regenerate the alcoholic solvent, which is led to a storage for reuse. The condensation polymer is depolymerized in the purified recovered alcoholic solvent by using a catalyst. A reactor system for carrying out the method is also described.

Abstract: The separation method separates a polyalcohol compound from water, so as to obtain a purified product stream comprising the polyalcohol compound in an output concentration of at least 90 wt %. Thereto, a mixture of the polyalcohol compound and water is provided, said mixture having a polyalcohol concentration. The polyalcohol concentration of the mixture is increased in an evaporation stage. Subsequently, the mixture is treated in a distillation stage to deliver the purified product stream comprising the polyalcohol compound in the output concentration of at least 90 wt %. Herein, the distillation stage is operated to produce steam output, that is optionally compressed to a steam pressure, and is coupled to the evaporation stage. The maximum distillation pressure and/or said compressed steam pressure is not less than the maximum evaporation pressure. The reactor system is configured for performing the separation method.

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: Method for depolymerising terephthalate polymer into reusable raw material, the method comprising steps of: depolymerizing terephthalate polymer by using ethylene glycol into a depolymerised mixture comprising at least one monomer and at least one dimer, wherein said at least one monomer comprises bis (2-hydroxyethyl) terephthalate (BHET), and said at least one dimer comprises dimer of bis (2-hydroxyethyl) terephthalate (BHET-dimer); removing solid compounds from said depolymerised mixture in a first separator to obtain a composition comprising the at least one dimer and the at least one monomer as solutes in a mixture of ethylene glycol and water; crystallizing BHET-dimer from said solution, thereby obtaining a mixture of BHET-dimer crystals and a first mother liquid; separating the crystallized BHET-dimer from the first mother liquid, and thereafter: forming BHET crystals from said first mother liquid, thereby obtaining a mixture of BHET crystals and a second mother liquid; and recovering the BHET crystals.

Abstract: The separation method separates a polyalcohol compound from water, so as to obtain a purified product stream comprising the polyalcohol compound in output concentration of at least 90 wt %. Thereto, a mixture of the polyalcohol compound and water is provided, said mixture having a polyalcohol concentration. The polyalcohol concentration of mixture is increased in an evaporation stage, at least a portion of which is operated in at first pressure. Subsequently, the mixture is treated in distillation stage to be deliver the stream comprising the polyalcohol compound in the output concentration of at least 90 wt %, which distillation stage is operated at a second pressure. Herein, the distillation stage is operated to produce steam output, that optionally compressed to a third pressure and is coupled to the evaporation stage. The second pressure and/or any third pressure is higher than first pressure. The reactor system is configured for performing the separation method.

Abstract: The present invention is in the field of fluids and the like comprising magnetic particles, such as ferromagnetic particles, anti-ferromagnetic particles, ferrimagnetic particles, synthetic magnetic particles, paramagnetic particles, superparamagnetic particles, such as magnetic fluids, a method of stabilizing magnetic particles, use of these fluids and functionalized particles. Such fluids have a large variety of applications, such as sealants, as a sensor, in biomedics, etc. The present invention is further directed to a method of obtaining a catalyst for use in the depolymerisation of polymers into oligomers and monomer.

Abstract: A method of degrading a polymer into oligomers and/or monomers in a solvent, using a catalyst, and a functionalized magnetic particle comprising a catalyst being capable of degrading the polymer into oligomers and/or monomers. The present method and particle provide a high selectivity and a high conversion ratio.

Abstract: A catalyst complex for catalysis of degradation of a polymer material is described. Said complex comprises a magnetic particulate body containing iron oxide at its surface with an average diameter of 150-450 nm, and a plurality of catalytic groups grafted onto the iron oxide surface of the magnetic particulate body, which catalytic groups comprise a bridging moiety and a catalyst entity, wherein the bridging moiety comprises a functional group for adhesion or bonding to the iron oxide surface and a linking group towards the catalyst entity, and wherein the catalyst entity comprises a positively charged aromatic heterocycle moiety, and a negatively charged moiety for balancing the positively charged aromatic moiety.

Abstract: An improved reusable capture complex and a method of capturing an additive releasable from a polymer material are disclosed. The capture complex includes a catalyst entity, a magnetic nanoparticle, and a bridging moiety between the catalyst entity and the magnetic nanoparticle. The method provides a high reduction of free additive of a polymer material.

Abstract: Methods of degrading a polymer into oligomers and/or monomers in a solvent, using a catalyst, and a functionalized magnetic particle comprising a catalyst being capable of degrading the polymer into oligomers and/or monomers are disclosed. The method and particle provide a high selectivity and a high conversion ratio.