EP4581098A1

EP4581098A1 - Process for thermal treatment of a multicomponent plastic waste material

Info

Publication number: EP4581098A1
Application number: EP23757647.5A
Authority: EP
Inventors: Caroline Beyer; Miika FRANCK; Peter HEIDEBRECHT; Britta Carolin BUCK; Achim Stammer; Alvaro GORDILLO BOLONIO
Original assignee: BASF SE
Current assignee: BASF SE
Priority date: 2022-08-31
Filing date: 2023-08-21
Publication date: 2025-07-09
Also published as: WO2024046793A1

Abstract

A process for thermal treatment of a multicomponent plastic waste material is provided, wherein the process comprises providing a multicomponent plastic waste material, including a first polymer material and a second polymer material; treating the first polymer material in a first thermal treatment in a first reactor at a first temperature; and treating the second polymer material in a second thermal treatment in a second reactor at a second temperature, which is higher than the first temperature.

Description

Process for thermal treatment of a multicomponent plastic waste material

The present invention relates to a process for thermal treatment of a multicomponent plastic waste material.

Products containing more than one plastic component, i.e., multicomponent plastic materials, are widely used in industry and in a plurality of everyday applications. Because of the tremendous and still increasing prevalence of multicomponent plastic materials, there is a large amount of waste of such materials. This waste of multicomponent plastic materials should be treated appropriately and as economically friendly as possible.

In view of the above, it is an object of the present invention to provide a process for thermal treatment of a multicomponent plastic waste material which is as easy as possible, and which enhances processability of the resulting components.

This object is accomplished by the provision of a process according to claim 1.

The process for thermal treatment of a multicomponent plastic waste material comprises providing a multicomponent plastic waste material, including a first polymer material, in particular polyamide material, and a second polymer material, in particular a polyolefin material.

In the alternative to a polyamide material, also polyvinyl chloride, polystyrene, polybutylene terephthalate, polycarbonate, or mixtures of thereof may be used as the first polymer material. In the following, polyamide and polyolefin are mentioned as exemplary materials since they are preferred options. However, according to the present invention, also other polymer materials can be used as first and second polymer materials.

The first polymer material, in particular the polyamide material, is thermally treated in a first thermal treatment in a first reactor at a first temperature.

According to a preferred embodiment, the first thermal treatment is a first pyrolysis and the first polymer material, in particular the polyamide material, is pyrolyzed at a first pyrolysis temperature.

It can be beneficial if a catalyst material is used during the first thermal treatment. The catalyst material is, according to a preferred embodiment, a particulate catalyst material and is used as a catalyst and/or bed.

The first reactor is preferably a first fluidized bed reactor.

The second polymer material, in particular the polyolefin material, is treated in a second thermal treatment in a second reactor at a second temperature.

According to a preferred embodiment, the second thermal treatment is a second pyrolysis and the second polymer material, in particular the polyolefin material, is pyrolyzed in a second pyrolysis at a second pyrolysis temperature.

Preferably, the second reactor is a second fluidized bed reactor.

The second temperature is higher than the first temperature. For example, the second pyrolysis temperature is higher than the first pyrolysis temperature. Preferably, the particulate catalyst material is used as bed in the second pyrolysis, too.

The first polymer material and the second polymer material are mutually different materials.

A fluidized bed - as present in the first fluidized bed reactor and the second fluidized bed reactor - is a physical phenomenon occurring when a quantity of a solid particulate substance (usually present in a reactor and, according to an embodiment of the invention, the particulate catalyst material) is placed under appropriate conditions to cause a solid/fluid mixture to behave like a fluid. A bed of particles can be partly or fully supported by an upward flow of fluid through interstices between the particles; if the bed is fully supported, it is said to be fluidized. This results in the particulate substance then having many properties and characteristics of normal fluids, such as the ability to flow freely under gravity, or to be conveyed using fluid type technologies.

The resulting phenomenon is called fluidization.

Due to the use of the fluidized bed reactors and corresponding fluidization, high heat transfer rates and mass transfer rates can be achieved. Due to the fluidization, heat can quickly be distributed over the entire reaction chamber in the respective reactor. Furthermore, due to the fluidization, a homogeneous temperature profile over the entire reaction chamber and over the entire reaction time can be obtained.

According to the present invention, the thermal treatment of the first polymer material, preferably the polyamide material, and the thermal treatment of the second polymer material, in particular the polyolefin material, are essentially spatially and/or timely separate from each other. Due to the separation of the first thermal treatment and the second thermal treatment, preferably in the first pyrolysis and the second pyrolysis, the corresponding products are separated inherently, too. This may simplify subsequent workup steps that are preformed after the first thermal treatment and the second thermal treatment.

The first reactor, for example the first fluidized bed reactor, and the second reactor, for example the second fluidized bed reactor, in particular differ from each other, for example spatially and/or thermally. However, it is also possible according to the invention, that the first reactor and the second reactor are formed by the same reactor used both for the first thermal treatment and for the second thermal treatment, for example subsequently.

According to a preferred aspect of the invention, the first reactor and the second reactor may be thermally coupled via a particulate catalyst material which is transported from one reactor to the other.

Due to the performance of two thermal treatment steps, a selective thermal treatment, for example a selective pyrolysis of the first polymer material, in particular the polyamide material, and the second polymer material, for example the polyolefin material, can be achieved.

In embodiments in which the thermal treatment steps are a first pyrolysis and a second pyrolysis, and in which the first polymer material is a nitrogen containing polymer material such as a polyamide material, the second pyrolysis in particular results in a pyrolysis oil having a reduced nitrogen content compared to pyrolysis oils resulting from a one-step pyrolysis of the same multicomponent plastic waste material comprising the polyamide material. The pyrolysis oil resulting from the second pyrolysis can be used in applications, in which a high nitrogen content in the pyrolysis oil (coming from the first nitrogen containing polymer material (e.g., polyamide)) is detrimental. With the process of the present invention, mass transfer limitations, which typically limit the pyrolysis of multicomponent polymer materials, e.g., a polyamide and polyolefin mix, can be overcome. With the process of the present invention, the particulate catalyst material can be used as a carrier for the second polymer material and both together can be continuously transported from the first reactor to the second reactor.

Preferably, after the first pyrolysis, the particulate catalyst material and the second polymer material, in particular polyolefin material, for example molten polyolefin material, are transported from the first fluidized bed reactor into the second fluidized bed reactor, preferably using gravimetric forces or pneumatically.

The first reactor, in particular the first fluidized bed reactor, and the second reactor, in particular the second fluidized bed reactor, are preferably connected via a first transfer line for transferring material from the first reactor to the second reactor and/or a second transfer line for transferring material from the second reactor to the first reactor.

In particular in order to avoid contamination of a first pyrolysis product and a second pyrolysis product, it can be beneficial if gas exchange between the first pyrolysis reactor and the second pyrolysis reactor is avoided.

In this regard, preferably one or more of the following elements includes a gas blocking element for blocking and/or reducing gas exchange between the first reactor, in particular the first fluidized bed reactor, and the second reactor, in particular the second fluidized bed reactor: the first reactor, in particular the first fluidized bed reactor; the second reactor, in particular the second fluidized bed reactor; the first transfer line; the second transfer line.

Preferred valves are mechanical valves, or non-mechanical valves, e.g., L-valves or loop seals.

The valves and/or sealing elements may be used with or without aeration in order to avoid contamination of material in either reactor. Inert gas may also be used in order to avoid contamination of the content of the first reactor and the second reactor. Even without an additional gas flow, an at least partial gas tightness between the first reactor and the second reactor can be obtained due to pressure losses of the bulk material, e.g., in an L-valve. If additional tightness is desired, gas, e.g., inert gas, can be used countercurrent to the direction of flow of the bulk material.

The gas blocking element(s) in particular serve as a control element for regulating and/or controlling and the transport of solids (e.g., the catalyst material) via a corresponding transfer line from one reactor to the other.

Due to the two-step thermal treatment, preferably the two-step pyrolysis, the second polymer material can be transferred to the second reactor together with the catalyst material after the first thermal treatment, e.g., the first pyrolysis, has been performed.

Preferably, the particulate catalyst material is a particulate material according to Group A or Group B of Geldart’s classification. More preferred, the particulate catalyst material is a material according to Group B of Geldart’s classification. According to Geldart’s classification, particles can be classified into four groups (i.e., Groups A, B, C, and D) based on their fluidization behavior. In this classification, density difference between the particles and the gas and the average particle diameter are taken into account. The classification is known, e.g., from D. Geldart: Types of gas fluidization, Powder Technology, vol 7, no. 5, May 1973, pages 285 to 292, doi:10.1016/0032-5910(73)80037-3.

Preferably, an average size of particles of the particulate catalyst material is from about 80 pm to about 800 pm, more preferred from about 100 pm to about 400 pm.

The average particle size is preferably determined by laser diffraction methods according to DIN ISO 13320, e.g., Beckman Coulter LS 13320 or Malvern Mastersizer 3000). The average particle size is preferably defined as an arithmetic mean of the diameters or diagonals through the particles.

Preferably, an average envelope density of particles of the particulate catalyst material is from about 1500 kg/m³ to about 4000 kg/m³, preferably from about 1800 kg/m³ to about 3000 kg/m³. The envelope density of the particles is defined as the ratio of the mass of a particle to the sum of the volumes of the solid in each piece and the voids within each piece, that is, within close-fitting imaginary envelopes completely surrounding each piece (ASTM D3766). The ratio of the mass of a particle to the envelope volume of the particle (implied by BSI). The envelope density is preferably determined by mercury pycnometry, e.g., ASTM Standard Test Method C493-93, Bulk Density and Porosity of Granular Refractory Materials by Mercury Displacement.

Preferably, the process is a continuous process. For example, the first reactor, for example the first fluidized bed reactor, and the second reactor, for example the second fluidized bed reactor, are mechanically and/or fluidically coupled. In particular, the particulate catalyst material and remaining multicomponent plastic waste material is transferred from the first fluidized bed reactor to the second fluidized bed reactor after the first pyrolysis.

In embodiments of the process, in which a polyamide material is used as first polymer material and in which a polyolefin material is used as second polymer material, it has been found to be beneficial, if the first temperature, for example the first pyrolysis temperature, is about 200 ° C or more, preferably about 225 ° C or more, in particular about 245 ° C or more, for example about 270 ° C or more. In particular, the first temperature, for example first pyrolysis temperature, is about 350 ° C or less, preferably about 325 ° C or less, for example about 310 ° C or less.

In the mentioned temperature ranges for the first temperature, the temperature is high enough that the first polymer material, in particular the polyamide material, for example polycaprolactam, is decomposed in the presence of the catalyst material. However, the temperature in the mentioned ranges is not high enough for the second polymer material, in particular the polyolefin material, for example polyethylene, to be changed in thermal treatment, in particular to be pyrolyzed. Thus, a selective thermal treatment, in particular a selective pyrolysis, can be performed.

Preferably, a residence time of the multicomponent plastic waste material in the first fluidized bed reactor is about 30 minutes or lower, preferably about 15 minutes or lower.

According to preferred embodiments, a reaction time for the first pyrolysis is about 2 minutes to about 30 minutes. The particulate catalyst material preferably comprises or consists of a particulate carrier material and a catalytically active material, wherein preferably the particulate carrier material is selected from one or more of the following substances: metal oxides, in particular alumina, for example a (alpha)-alumina, silica, for example fumed silica, carbides, for example silicon carbide, tungsten carbide or mixtures thereof.

Preferably, the catalytically active material is a base, in particular an alkali metal oxide, an alkali metal hydroxide, for example potassium hydroxide (KOH) or sodium hydroxide (NaOH) or a mixture thereof, an alkali metal carbonate or a mixture of two or more of the mentioned materials.

For example, particles of the particulate carrier material which are impregnated and/or doped with the catalytically active material are used as particulate catalyst material.

In accordance with a preferred example, the particulate catalyst material comprises about 0.5 wt.-% or more and/or about 22 wt.-% or less of an alkali metal, based on a total weight of the particulate catalyst material. Preferably, the alkali metal is potassium (K). In particular, the alkali metal is part of the catalytically active material of the catalyst material.

For the preparation of the catalyst material, preferably, the carrier material is impregnated with a solution containing the catalytically active material. For example, the carrier material is impregnated with an aqueous potassium hydroxide solution.

In order to obtain reproducible results, preferably, the carrier material is impregnated with the solution containing the catalytically active material so that essentially all internal pores of the carrier material are filled with solution containing the catalytically active material. In this way, a steady state concerning solution uptake of the carrier material can be reached.

After bringing the carrier material into contact with the solution containing the catalytically active material, preferably, the carrier material soaked with the catalytically active material is dried.

For drying, preferably, the carrier material soaked with the catalytically active material solution is dried for 2 h or more, in particular for 15 h or more, for example for 16 h. For example, the carrier material soaked with the catalytically active material solution is dried at a temperature from about 80 ° C to about 160 ° C, preferably at a temperature from about 110 ° C to about 130 ° C, for example, at about 120 ° C.

Upon drying of the carrier material soaked with the catalytically active material, raw particulate catalyst material is formed.

The raw particulate catalyst material can be processed to particulate catalyst material, for example, by calcination. Preferably, the raw particulate catalyst material is calcined, for example in air, at a temperature of about 450 ° C to about 550 ° C, in particular at a temperature of about 475 ° C to about 525 ° C, for example, at a temperature of about 500 ° C.

As calcination time, about 1 h to about 3 h, for example about 2 h, is preferred.

In order to optimize the size distribution of the particulate catalyst material, a separating device, for example a sieve, is used. Preferably, the particulate catalyst material is pressed through the separating device, before being used in a fluidized bed reactor, for example, after calcination. Due to the use of the separating device, agglomerates that have formed during drying and/or calcination can be separated.

The particulate catalyst material preferably comprises one or more of the following: alkali metal oxide, for example potassium oxide (K₂O), mixed oxides, for example a mixed oxide between potassium oxide and alumina (K₂O-AI₂O₃).

It can be beneficial to dry the particulate catalyst material immediately prior to the first pyrolysis. Preferably, prior to pyrolysis, the bed material is heated up to the first pyrolysis temperature under dry nitrogen atmosphere.

It is beneficial to use particulate catalyst particles that are essentially non-porous, in particular to use a catalyst material, exhibiting essentially no open porosity.

According to the present invention, “essentially non-porous” means that the respective material has a BET surface area of about 25 m²/g or less, in particular about 2 m²/g, or less. The BET surface area has been determined according to BS ISO 9277:2010; determination of the specific surface area of solids has been performed by gas adsorption. Due to the low porosity of the particulate catalyst material, the lengths of transport paths of the first polymer material, in particular the polyamide material, and a resulting decomposition product, for example caprolactam in the case of polycaprolactam as polyamide material, can be reduced compared to a catalyst material having open pores and/or a higher porosity.

In particular, for pores of a certain size, the first polymer material, in particular the polyamide material, and a resulting decomposition product, for example caprolactam in the case of polycaprolactam as polyamide material, can, due to size restrictions, not be entered by the respective material. Thus, the surface area of all pores of this certain size and smaller is inaccessible for the reaction. In these cases, the accessible surface area may be larger with lower porosity.

During fluidization of the particulate catalyst material (forming the bed of the respective fluidized bed reactors) a layer of the second polymer material, in particular the polyolefin material, deposited on particles of the particulate catalyst material is broken up due to particle collisions. Since thus the first polymer material can thus be brought into contact with the catalyst material, this (breaking up of the layer of material) may foster the first pyrolysis of the first polymer material, in particular the polyamide material.

According to a preferred embodiment, the particulate catalyst material and the multicomponent plastic waste material are used in a weight ratio from about 2:1 to about 25:1, preferably about 3:1 to about 5:1, in the first fluidized bed reactor.

As already mentioned, during the second pyrolysis, a pyrolysis oil is formed. The resulting pyrolysis oil preferably has a nitrogen content that is about 85 % or more, preferably about 90 % or more, smaller than the nitrogen content in original multicomponent plastic waste material.

The nitrogen content of the pyrolysis oil is preferably determined by chemiluminescence methods. A sample to be analyzed is diluted (if needed) and an aliquot is combusted in the instrument at about 1000° C under argon and oxygen atmosphere. The detection is performed via chemiluminescence. This method is a modification of DIN 51444:2020-10. This method is used for nitrogen concentrations up to ca. 0.5 g/100 g. If a nitrogen concentration is above 0.5 g/100 g, the sample (1 mg to 10 mg) to be analyzed is combusted in a helium or oxygen atmosphere and resulting NOx is subsequently reduced to nitrogen. After separation of the combustion gases, the nitrogen concentration is determined and quantified as N2 via thermal conductivity. As elemental analyzer Elementar, model Vario EL Cube can be used.

The nitrogen content in the multicomponent polymer material is determined according Kjeldahl digestion and water steam distillation. A sample to be analyzed is digested with concentrated sulfuric acid and a catalyst. According to Kjeldahl, all nitrogen species are converted into ammonium sulfate after digestion. Sodium hydroxide is added to the digest, and ammonia is transferred into a receiving solution by means of water steam distillation. The final determination is performed by means of photometry or ion chromatography. This method is used for nitrogen concentration up to about 0.5 g/100 g.

If the nitrogen content in the multicomponent polymer material is above about 0.5 g/100 g, a sample to be analyzed (1 mg to 10 mg) is combusted in an atmosphere of helium and oxygen and the formed NOx subsequently reduced to N2. After separation of the combustion gases, nitrogen is determined and quantified as N2 via thermal conductivity. As elemental analyzer, the elemental analyzer Elementar, model Vario EL Cube, can be used.

According to a preferred embodiment, the first fluidized bed reactor and/or the second fluidized bed reactor each comprise a plenum, a gas distributor and a fluidized bed.

The fluidization gas is introduced into the plenum, which may also be referred to as windbox. In particular, the plenum is designed to homogeneously distribute the fluidization gas and/or to secure a homogeneous entry of the fluidization gas into the gas distributor, respectively.

The gas distributor is located between the plenum and the fluidized bed and is designed for homogeneous fluidization of the bed, in particular by homogeneously distributing gas flow of the fluidization gas through all orifices of the respective gas distributor. In particular, the gas distributor can prevent backflow of solids into the plenum. In particular the orifices of the gas distributor are designed to minimize erosion of the orifices and attrition of the catalyst material and/or bed material. In particular for homogeneous gas distribution, the plenum/windbox may, for example, comprise one or more of the following elements: gas deflection device, multiple inlet gas points and/or sparger type gas distribution system. The sparger type gas distribution system is typically located below a main gas distributor.

The one or more orifices of the respective gas distributor are preferably designed so that one or more specific properties of jets flowing though the respective fluidized bed are adjusted and allow for a homogeneous gas distribution over the reactor.

Preferably, the pressure difference of the gas distributor is above 20 mbar and the pressure difference of the gas distributor is 0.1 times to 0.3 times the pressure difference of the fluidized bed.

The one or more specific properties are preferably adjusted due to the one or more orifices in a way that attrition of the catalyst material and/or bed material is minimized or avoided.

For example, a mass flow of the respective jet is reduced and/or decreased by the one or more orifices of the gas distributor.

According to preferred embodiments, the respective gas distributor has one or more orifices in the form of bubble caps, nozzles or the gas distributor can be a sparger-type gas distributor.

In particular for homogeneous gas distribution, it can be beneficial, if the respective gas distributor has an inclination and/or a curvature. For example, the respective gas distributor comprises a grid-like system having an opening at each end (the end adjacent to the plenum and the adjacent to the bed). The openings preferably serve as discharging elements in order to discharge undesired agglomerates which have been formed during the respective thermal treatment step, for example the first pyrolysis or the second pyrolysis.

Discharged agglomerates can be regenerated or discarded.

Gas distributors containing sparging devices can be used, according to a preferred embodiment, for secondary gas injection into the respective bed. Preferably, the gas distributors are designed in such a way that undesired agglomerates formed during the thermal treatment can be discharged from the respective bed.

According to a preferred embodiment, the first fluidized bed and/or the second fluidized bed each may comprise one or more heat transfer devices. Heat transfer devices may be internally, i.e., located essentially inside a body of the respective reactor containing the respective fluidized bed, or externally, i.e., located essentially outside of the reactor.

For example, an internal heat transfer device can be a pipe-like and/or a rod-like element or bundle of pipe-like and/or rods-like elements immersed into the respective fluidized bed.

It can be beneficial, if the first fluidized bed and/or the second fluidized bed each comprise a freeboard designated to retain ejected solids from the respective fluidized bed surface and carried up by the fluidization gas. For example, the freeboard has an increased diameter in comparison to the average diameter of the respective fluidized bed. The diameter is preferably defined perpendicular to a main direction of flow of the fluidization gas. Due to the increased diameter, the superficial gas velocity in the area of the freeboard is decreased.

In particular in order to separate particles that are carried upwards in a main direction of flow of the fluidization gas, the first fluidized bed and/or the second fluidized bed comprises one or more separation elements. The one or more separation elements can, for example, be a cyclone, for example arranged inside a respective reactor (internal) or outside the respective reactor (external). In the alternative or additionally, the one or more separation elements can be a filter, preferably a heated filter, for example arranged inside a respective reactor (internal) or outside the respective reactor (external).

One advantage of external cyclones and filters is that it is possible to influence the holdup of particles having a particle size of below 40 pm (the so-called fines) in the system by either feeding the separated fines back into the reactor or discarding the fines.

Preferably, during the first pyrolysis, a first pyrolysis product fluid, for example a first pyrolysis product gas, is formed which is transported by a fluidization gas into a first workup system. In particular, the first pyrolysis product fluid comprises or consists of polyamide monomer, in particular a cyclic lactam, for example, caprolactam, or a diamine or a mixture thereof. Preferably, the system for pyrolyzing a multicomponent plastic waste material comprises a first work-up system for separating the first pyrolysis product fluid from a fluidization gas and a second work-up system for separating a pyrolysis oil (or condensable species) resulting from the second pyrolysis from the fluidization gas and from generated pyrolysis gases and/or flue gases.

For example, the first work-up system comprises of one or more condensers and/or one or more gas scrubbers.

In particular, the one or more condensers are operated at a temperature of above or close to the melting point of the first pyrolysis product fluid. For example, if the first pyrolysis product fluid contains or basically consists of caprolactam, the one or more condensers are operated at about 70° C or more. In embodiments, in which the first work-up system comprises more than one condenser, the more than one condensers are preferably operated in sequence.

Preferably, the one or more gas scrubbers are operated at a temperature of about 20° C or more and/or about 40° C or less. For example, the one or more gas scrubbers are cooled by a heat transfer fluid, for example water or air. In embodiments, in which the first work-up system comprises more than one gas scrubber, the more than one gas scrubbers are preferably operated in sequence.

Preferably, the first work-up system comprises one or more cooling elements, in particular one or more coolers, for example operated at a temperature so that the first pyrolysis product fluid is cooled to room temperature, e.g., 20° C.

The gas scrubbers can be operated with different scrubbing liquids, preferably with scrubbing liquids in which the respective pyrolysis product fluid is soluble. For example, if a cyclic lactam, for example caprolactam, or a diamine or a mixture thereof is part or forms the first pyrolysis product fluid water may be used as scrubbing liquid.

Another example for a scrubbing liquid to be used to clean the first pyrolysis product fluid, is the use of caprolactam itself also as scrubbing liquid. In the latter case the respective gas scrubber is preferably heated to above the melting point of the pyrolysis product fluid. In case of caprolactam this is above 70° C. Due to the generation of harmful gaseous compounds during the first pyrolysis and/or the second pyrolysis, preferably generated off-gases are treated. This can be done by scrubbing and/or combustion of the off gases. Such harmful gases are, for example, hydrogen cyanide (HCN), acetonitrile, acrylonitrile, ammonia (NH3), and other nitrogen containing compounds.

In particular to reach legal waste gas concentration limits, further gas cleaning elements and/or methods can be used as part of the respective work-up system, such as, one or more of the following: one or more additional condensers, one or more additional scrubbers, one or more electrostatic precipitators, one or more adsorbers and or other typical gas cleaning steps.

Preferably, the first work-up system further comprises a hot gas filter which is in the direction of flow of the first pyrolysis product fluid positioned upstream from any further element, such as the one or more gas scrubbers, of the first work-up system.

In addition or in the alternative to the hot gas filter, the work-up system can comprise one or more cyclones.

Preferably, the first fluidized bed reactor and/or the second fluidized bed reactor are fluidized with a fluidization gas which is an inert gas, such as nitrogen or preferably recycle gas.

In lab-scale setup, a gas flow rate of the fluidization gas is presently 1500 Nl/h or lower.

Preferably, a ratio of superficial fluidization to minimal fluidization is 4 or higher.

At ambient conditions, a minimum fluidization velocity of the particulate catalyst material should be about 0.2 cm/s or more and/or about 40 cm/s or less, preferably about 1 cm/s or more and/or 20cm/s or less. In particular, the minimum fluidization velocity is about 2 cm/s or more and/or lOcm/s or less.

As described above, the polyamide material, for example polycaprolactam, is preferably removed from the first fluidized bed reactor during and/or after the first pyrolysis by depolymerization. During the first pyrolysis, the second polymer material, in particular the polyolefin material, for example polyethylene, is essentially not pyrolyzed and/or decomposed.

Preferably, after the first pyrolysis, the particulate catalyst material is partially or completely covered and/or physically connected with the second polymer material, in particular the polyolefin material. The thickness of a layer of the second polymer material, in particular the polyolefin material, should be small enough so that bed agglomerations are avoided but high enough so that as much of the second polymer material as possible can be transported per catalyst material particle. Thus, there is a threshold for the layer thickness.

This threshold can be evaluated by introducing a critical polymer layer thickness <5crit. If the polymer layer thickness 8 on the bed material particles is smaller than <5crit, a momentum of two colliding catalyst material particles is larger than the viscous force of the forming bridge of the second polymer material between these particles. Therefore, if the polymer layer thickness is smaller than the critical polymer layer thickness <5crit, the polymer bridge will break and the two particles rebound. If the polymer layer thickness 8 equals or is larger than the critical polymer layer thickness <5crit, the viscous forces equal or exceed the momentum force of the two particles. Thus, if the polymer layer thickness equals or is larger than the critical polymer layer thickness <5crit, the polymer bridge will not break, and the particles stick together.

The critical polymer layer thickness <5crit is defined by the following equation: wherein r is the particle radius; m_p is the particle mass; v₀ is the impact velocity; and p is the viscosity of the molten polymer, i.e., of the second polymer material.

The particle mass m_p can be determined according to the following equation: wherein, mcat i^s the mass of a particle of the catalyst material; m_poi is the mass of the polymer, i.e., the second polymer material; d_p is the diameter of a particle;

Peat i^s the density of the catalyst material; p_poi is the density of the polymer material, i.e., the second polymer material.

It has been observed that a complete or partial coating of polyolefin material can be formed around particles of the particulate catalyst material after the polyamide material has reacted and/or decomposed during the first pyrolysis.

After the first pyrolysis, the catalyst material and remaining plastic waste material, in particular molten polyolefin material, are transported from the first fluidized bed reactor into the second fluidized bed reactor, preferably pneumatically and/or by using gravimetric forces.

After the particulate catalyst material covered with the second polymer material, in particular the polyolefin material, have been transported into the second fluidized bed reactor, the second pyrolysis is performed.

The second pyrolysis temperature is preferably about 400 ° C or more, preferably about 475 C or more, in particular about 495 ° C or more and/or about 650 ° C or less, preferably about 600 ° C or less, in particular about 550 ° C or less.

During the second pyrolysis, preferably, a second pyrolysis product fluid is formed, which is transported by a fluidization gas into a second work-up system. For example, the second pyrolysis product fluid is in the form of a vaporized product, which is afterwards condensed and/or separated from the fluidization and pyrolysis gases.

The second work-up system preferably comprises a condenser element for condensing pyrolysis oil from the second pyrolysis product fluid and separating the pyrolysis oil from permanent gases of the second pyrolysis product fluid.

In particular after the second thermal treatment, for example the second pyrolysis, the catalyst material is reconditioned in a conditioning system by combusting deposits, for example pyrolysis char. For example, the conditioning system is part of the pyrolysis system for pyrolyzing a multicomponent plastic waste material. In an alternative embodiment, the conditioning system is a distinct system.

The conditioning system can be part of the second reactor, in particular the second fluidized bed reactor.

For example, the particulate catalyst material is together with second polymer material, in particular polyolefin material, transported from the first fluidized bed reactor to the second fluidized bed reactor, e.g., via a first transfer line.

The conditioning system preferably comprises a heat transfer unit, for example a heat transfer tube, which connects the first transfer line and the second fluidized bed reactor. In particular, the heat transfer unit protrudes into the second fluidized bed reactor from one end of the reactor, which is opposite to the end, where the fluidization gas is introduced.

In embodiments, in which the conditioning system is a part of the second fluidized bed reactor, preferably, the heat transfer device encloses an inner space, and is enclosed by an outer space. Both, the inner space and the outer space are part of the second fluidized bed reactor. The outer space is preferably enclosed by the wall of the second fluidized bed reactor.

During operation of the pyrolysis system, the particulate catalyst material has in the inner space a main direction of flow which is countercurrent to the main direction of flow of the particulate catalyst material in the outer space.

In embodiments, in which the conditioning system is a part of the fluidized bed reactor, preferably, the second fluidized bed reactor has, during operation, a pyrolysis zone in which the second polymer material is pyrolyzed at the second pyrolysis temperature.

In embodiments, in which the conditioning system is a part of the fluidized bed reactor, preferably, the second fluidized bed reactor has, during operation, a heat transfer zone in which heat is transferred to the particulate catalyst material which is adjacent to the particulate catalyst material within the pyrolysis zone via the heat transfer device. Adjacent to the inlet of the fluidization gas, the second fluidized bed reactor has, during operation, preferably a combustion zone in which deposits on the particulate catalyst material are combusted. In this regard, preferably lean air is used as fluidization gas, so that there is enough oxygen to combust the deposits, but not enough oxygen to oxidize material during the second pyrolysis.

According to another aspect of the invention, the conditioning system is spatially distinct from the second fluidized bed reactor.

In embodiments, in which the conditioning system is separate from the second fluidized bed reactor, the conditioning system in particular comprises a separate regeneration unit, e.g., a third fluidized bed reactor.

Preferably the particulate catalyst material is transported into the regeneration unit, where the deposits are combusted. Generated heat and flue gas can be dissipated and used for heating. After the reconditioning, the particulate catalyst material is preferably recirculated back to the second fluidized bed reactor or recirculated to the first fluidized bed reactor.

Preferably, the overall pyrolysis system including the first reactor, the second pyrolysis reactor and the conditioning system is operated autothermally.

According to a preferred aspect of the invention, the pyrolysis char can be combusted in the second pyrolysis reactor. For example, (lean) air is fed into the second reactor at a lower end (regarding the gravitational direction). Consequently, char is combusted, and solids are heated. An oxygen content within the second reactor is preferably adjusted such that essentially no second polymer material is combusted and/or oxidized.

As already described above, the conditioning system can be integrated into the second fluidized bed reactor.

The conditioning system can be used for startup and/or shutdown of the pyrolysis system for pyrolyzing the multicomponent plastic waste material and/or for regeneration of the particulate catalyst material. In particular, the conditioning system can be used to heat up the overall pyrolysis and a conditioning reactor system by combusting fuels such as natural gas, fuel oil, coal, pyrolysis products, plastics or other refuse derived fuels.

For regeneration of the catalyst material, it is beneficial if the fluidization gas comprises a combustion gas, for example, air or other oxidizing gases. Pyrolysis gases may be added during regeneration for co-combustion. Preferably, the polyamide material comprises or consists of one or more of the following materials: aliphatic polyamides, in particular polycaprolactam, for example known under the trade name Nylon 66, Nylon 6 or other Nylon types, or co-polymers or mixtures of the mentioned polyamide materials, polyvinyl chloride, polystyrene, polybutylene terephthalate, polycarbonate.

Polycaprolactam corresponds to Poly(azepan-2-one); poly(hexano-6-lactam). Nylon 66 corresponds to Poly[imino(l,6-dioxohexamethylene)iminohexamethylene].

The polyolefin material as second polymer material preferably comprises or consists of one or more of the following materials: polyethylene, polypropylene, polybutene or mixtures thereof.

As second polymer material, preferably a polymer material having a decomposition temperature, in particular in the presence of the catalyst material, which is more than 20

C higher than the decomposition temperature of the first polymer material, for example of more than about 325 ° C, is used. In this way, it can be assured that the second polymer material is not decomposed during the first thermal treatment.

The use of a multicomponent plastic waste material comprising or consisting of polycaprolactam (polyamide 6) and polyethylene is particularly beneficial. This material can be selectively pyrolyzed with optimized results since polycaprolactam and polyethylene are pyrolyzed at different temperatures. The temperature difference between the respective pyrolysis temperatures is further increased due to the use of the catalyst material.

For example, a multicomponent plastic waste material having a polyamide content of about 5 wt.-% or more, preferably of about 7 wt.-% or more, based on the total weight of the multicomponent plastic waste material, can be used.

According to a preferred example, a multicomponent plastic waste material having a polyamide content of 25 wt.-% or more, based on the total weight of the multicomponent polymer waste material, can be used. Preferably, the multicomponent plastic waste material is comminuted in one or more than one steps. For comminution, for example, one or more of the following techniques are used: shredder, cutting mill, ultracentrifugal mill.

For example, in a first comminution step, the multicomponent plastic waste material is comminuted to a size from about 2.5 mm to about 3.5 mm. In a second comminution step, preferably, the already comminuted multicomponent plastic waste material is further comminuted to a size from about 0.5 mm to about 1.0 mm. However, it is also possible that the comminution is performed in only one step.

The inventors have observed that multicomponent plastic waste material with a particle size of about 0.2 mm or more and/or about 4 mm or less is particularly suitable as feedstock material to be fed into the first fluidized bed reactor.

Due to the comminution of the multicomponent plastic waste material, a defluidization can be avoided.

For example, a conversion rate of polycaprolactam to caprolactam of 85 % or more can be reached.

In the alternative to introducing comminuted multicomponent plastic waste material, the material might be introduced into the pyrolysis unit in a molten state.

The invention further relates to a thermal treatment system for thermally treating a multicomponent plastic waste material, in particular a pyrolysis system for pyrolyzing a multicomponent plastic waste material.

In this regard, it is an object of the present invention to provide a thermal treatment system which is suitable to thermally treating a multicomponent plastic waste in an efficient way.

This object is solved by the pyrolysis system according to the independent claim directed to a thermal treatment system.

The thermal treatment system, in particular the pyrolysis system, is configured to be used in a process according to the present invention. The thermal treatment system for thermally treating a multicomponent plastic waste material comprises a first reactor for thermal treatment of a first polymer material in a first thermal treatment at a first temperature; and a second reactor for thermal treatment of a second polymer material in a second thermal treatment at a second temperature.

Preferably, the thermal treatment system is a pyrolysis system for pyrolyzing a multicomponent plastic waste material and comprises a first fluidized bed reactor for pyrolyzing a fist polymer material, in particular a polyamide material, in a first pyrolysis at a first pyrolysis temperature. The pyrolysis system further comprises a second fluidized bed reactor for pyrolyzing a second polymer material, in particular a polyolefin material, in a second pyrolysis at a second pyrolysis temperature.

In accordance with a preferred embodiment, the pyrolysis system comprises a first work-up system for work-up of a first pyrolysis product fluid, obtained during the first pyrolysis. The first work-up system is preferably directly coupled to the first fluidized bed reactor.

Preferably, the pyrolysis system comprises a second work-up system for work-up of the second pyrolysis product fluid, obtained during the second pyrolysis. The second work-up system is preferably directly coupled to the second fluidized bed reactor.

It is beneficial if the pyrolysis system comprises a conditioning system for adjusting the temperature during startup and/or shutdown of the pyrolysis system and for regenerating the particulate catalyst material.

All advantages and/or features described in connection with the process for thermal treatment of a multicomponent plastic waste material apply for the thermal system for thermally treating a multicomponent plastic waste material, too.

The invention further relates the use of a particulate catalyst material in a process for thermally treating, in particular pyrolyzing, a multicomponent plastic waste material, in particular in a process of the present invention, wherein the particulate catalyst material is essentially non-porous.

The invention further relates to a process, preferably according to the process described herein, wherein a first pyrolysis product fluid (105) and/or polyamide monomer, in particular a cyclic lactam, for example, caprolactam, or a diamine or a mixture thereof, is obtained from the first pyrolysis of the first polymer; and/or wherein a second pyrolysis product fluid (122) is obtained from the second pyrolysis of the second polymer; and wherein the process comprises the step: converting the first pyrolysis product fluid (105) and/or polyamide monomer and/or the second pyrolysis product fluid (122) obtainable by or obtained by the process described herein from the first pyrolysis and/or from the second pyrolysis or a chemical material obtainable by or obtained by the process according to any one of claims 1 to 13 to obtain a monomer, polymer or polymer product.

The invention further relates to a process comprising the step: using the thermal treatment system as described herein to obtain a purified pyrolysis oil, monomer, polymer or polymer product.

In a preferred embodiment, the monomer is a di- or polyol; preferably butandiol; aldehyde; preferably formaldehyde; di- or polyisocyanate; preferably methylene diphenyl diisocyanate (MDI), polymeric methylene diphenyl diisocyanate (pMDI), toluene diisocyanate (TDI), hexamethylenediisocyanate (H DI) or isophoronediisocyanate (IPDI); amide; preferably caprolactam; alkene; preferably styrene, ethene and norbornene; alkyne, (di)ester; preferably methyl methacrylate; mono or diacid; preferably adipic acid or terephthalic acid; diamine; preferably hexamethylenediamine, nonanediamine; or sulfones; preferably 4,4'- dichlorodiphenyl sulfone.

In a preferred embodiment, the polymer is and/or the polymer product comprises polyamide (PA); preferably PA 6 or PA 66; polyisocyanate polyaddition product; preferably polyurethane (PU), thermoplastic polyurethane (TPU), polyurea or polyisocyanurate (PIR); low-density polyethylene (LDPE), high-density polyethylene (HDPE), polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC), polyvinyl acetate (PVA), polystyrene (PS), poly acrylonitrile butadiene styrene (ABS), poly styrene acrylonitrile (SAN), poly acrylate styrene acrylonitrile (ASA), polytetrafluoroethylene (PTFE), poly(methyl acrylate) (PMA), poly(methyl methacrylate) (PMMA), polybutadiene (BR, PBD), poly(cis-l,4-isoprene), poly(trans-l,4-isoprene), polyoxymethylene (POM), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polybutylene adipate co-terephthalate (PBAT), polyester (PES), polyether sulfone (PESU), polyhydroxyalkanoate (PHA), poly-3-hydroxybutyrate (P3HB), poly-4-hydroxybutyrate (P4HB), polyhydroxyvalerate (PHV), polyhydroxyhexanoate (PHH), polyhydroxyoctanoate (PHO), polylactic acid (PLA), polysulfone (PSU), polyphenylene sulfone (PPSU), polycarbonate (PC), polyether ether ketone (PEEK), poly(p- phenylene oxide) (PPO), poly(p-phenylene ether) (PPE); or copolymer or mixture thereof; preferably polyamide (PA); more preferably PA 6.

In a preferred embodiment, the polymer and/or the polymer product is/are or is/are a part of: a part of a car; preferably cylinder head cover, engine cover, housing for charge air cooler, charge air cooler flap, intake pipe, intake manifold, connector, gear wheel, fan wheel, cooling water box, housing, housing part for heat exchanger, coolant cooler, charge air cooler, thermostat, water pump, radiator, fastening part, part of battery system for electromobility, dashboard, steering column switch, seat, headrest, center console, transmission component, door module, A, B, C or D pillar cover, spoiler, door handle, exterior mirror, windscreen wiper, windscreen wiper protection housing, decorative grill, cover strip, roof rail, window frame, sunroof frame, antenna panel, headlight and taillight, engine cover, cylinder head cover, intake manifold, airbag, cushion, or coating; a cloth; preferably shirt, trousers, pullover, boot, shoe, shoe sole, tight or jacket; an electrical part; preferably electrical or electronic passive or active component, circuit board, printed circuit board, housing component, foil, line, switch, plug, socket, distributor, relay, resistor, capacitor, inductor, bobbin, lamp, diode, LED, transistor, connector, regulator, integrated circuit (IC), processor, controller, memory, sensor, microswitch, microbutton, semiconductor, reflector housing for light-emitting diodes (LED), fastener for electrical or electronic component, spacer, bolt, strip, slide-in guide, screw, nut, film hinge, snap hook (snap-in), or spring tongue; a consumer, agricultural product or pharmaceutical product; preferably tennis string, climbing rope, bristle, brush, artificial grass, 3D printing filament, grass trimmer, zipper, hook and loop fastener, paper machine clothing, extrusion coating, fishing line, fishing net, offshore line and rope, vial, syringe, ampoule, bottle, sliding element, spindle nut, chain conveyor, plain bearing, roller, wheel, gear, roller, ring gear, screw and spring dampers, hose, pipeline, cable sheathing, socket, switch, cable tie, fan wheel, carpet, box or bottle for cosmetics, mattress, cushion, insulation, detergent, dishwasher tabs or powder, shampoo, body wash, shower gel, soap, fertilizer, fungicide, or pesticide; a packaging for the food industry; preferably mono- or multi-layer blown film, cast film (mono- or multi-layer), biaxial ly stretched film, or laminating film; or a part of a construction; preferably a rotor blade, insulating material, frame, housing, wall, coating, or separating wall.

In a preferred embodiment, the content of the multicomponent plastic waste material (102) in the monomer, polymer and/or polymer product is 1 weight-% or more, preferably 2 weight-% or more, more preferably 5 weight-% or more, more preferably 15 weight-% or more, more preferably 30 weight-% or more, more preferably 40 weight-% or more, more preferably 60 weight-% or more, more preferably 80 weight-% or more, more preferably 90 weight-% or more, more preferably 95 weight-% or more; and/or the content of the multicomponent plastic waste material (102) in the monomer, polymer and/or polymer product is 100 weight-% or less, preferably 95 weight-% or less, more preferably 90 weight-% or less, more preferably 50 weight-% or less, more preferably 25 weight-% or less, more preferably 10 weight-% or less; and preferably the content is determined based on identity preservation and/or segregation and/or mass balance and/or book and claim chain of custody models, preferably based on mass balance, preferably the International Sustainability and Carbon Certification (ISCC) standard.

The converting step(s) to obtain the monomer, polymer or polymer product may comprise one or more synthesis steps and can be performed by conventional synthesis and technics well known to a person skilled in the art. Independent of the person skilled in the art to assess novelty and inventive step of the independent claim(s), the person skilled in the art to perform the converting step(s) is preferably from the technical field(s) pyrolysis, gasification, remonomerization, depolymerization, synthesis, production of monomers, polymers and polymer compounds, and/or its further processing (e.g. extrusion, injection molding). Examples of the step(s) of the conversion is/are described in “Industrial Organic Chemistry”, 3. volume, Wiley-VCH, 1997, ISBN: 978-3-527-28838-0, „Kunststoffhandbuch“, 11 volumes in 17 sub-volumes, Carl Hanser Verlag; especially volume 6, „Polyamide“, 1. edition, 1966, volume 7, „Polyurethane", 3. edition, 1993, and volume 8, “Polyester”, 1. edition 1973; “Industrial Organic Chemistry”, 3. volume, Wiley-VCH, 1997, ISBN: 978-3-527- 28838-0, “Injection Molding Reference Guide, 4th edition, CreateSpace Independent Publishing Platform, 2011, ISBN: 978-1466407824, EP0989146 (Al), EP1460094 (Al), W02006034800 (Al), EP1529792 (Al), W02006042674 (Al), EP0364854 (A2), US5506275 (A), EP0897402 (Al), WO2015082316 (Al), WO2021021855 (Al), WO2021126938 (Al), W02021021902 (Al), W02021092311 (Al), WO2008155271 (Al), WO2013139827 (Al), each of which is incorporated herein by reference.

All advantages and/or features regarding the catalyst material described in connection with the process for thermal treatment of a multicomponent plastic waste material apply for the use of the particulate catalyst material, too.

For the purposes of producing advantageous embodiments of the invention, particular ones or several of the features described in this description and the accompanying claims can be utilized or omitted at will in combination with further features or independently of further features.

Further preferred features and/or advantages of the present invention form the subject matter of the following description and the graphical illustration of an exemplary embodiment.

In the Figures:

Figure 1 schematically shows an embodiment of a process for pyrolyzing a multicomponent plastic waste material, wherein a first component of the multicomponent plastic waste material is pyrolyzed in a first pyrolysis at a first pyrolysis temperature in a first fluidized bed reactor under the use of a catalyst material and wherein a second component of the multicomponent plastic waste material is pyrolyzed in the second fluidized bed reactor in a second pyrolysis at a second pyrolysis temperature, which is higher than the first pyrolysis temperature, wherein the process is performed in a pyrolysis system;

Figure 2 schematically shows a part of the process for thermal treatment of a multicomponent plastic waste material on a lab scale in which polycaprolactam is pyrolyzed in the first fluidized bed reactor, wherein resulting caprolactam is cleaned in a first work-up system;

Figure 3 schematically shows the part of the process in which the polyamide material of the multicomponent plastic waste material is pyrolyzed in the first pyrolysis, wherein a resulting first pyrolysis product gas is worked-up in a first work-up system of the pyrolysis system; Figure 4A schematically shows a flow chart of a first embodiment of a conditioning system for combustion and/or regeneration of the catalyst material, wherein the conditioning system is integrated into the second fluidized bed reactor and the catalyst material is regenerated in the second fluidized bed reactor;

Figure 4B schematically shows a flow chart of a second embodiment of a conditioning system for combustion and/or regeneration of the catalyst material, wherein the conditioning system is not part of the second fluidized bed reactor and wherein the catalyst is regenerated in a separate unit;

Figure 4C schematically shows an embodiment of the pyrolysis system during operation, in which the conditioning system is integrated in the second fluidized bed reactor, wherein a pyrolysis zone is established which is enclosed by a heat transfer zone and wherein deposits on catalyst particles are combusted in a combustion zone using oxygen from the fluidization gas; and

Figure 5 schematically shows a part of the process in which the polyolefin material of the multicomponent plastic waste material is pyrolyzed in the second pyrolysis, wherein a resulting second pyrolysis product fluid is worked-up in a second work-up system of the pyrolysis system.

Identical or functionally equivalent elements are designated in all figures with the same reference signs.

Figure 1 schematically shows an embodiment of a process for pyrolyzing a multicomponent plastic waste material 102, preferably a multilayer foil comprising or consisting of a polyamide material and a polyolefin material.

The pyrolysis is one example for a thermal treatment.

The process is preferably performed with and in a pyrolysis system 100.

The process is schematically shown as a whole in Figure 1. Different parts and/or aspects of the process and/or the pyrolysis system 100 are further illustrated in Figures 2 to 5. Preferably, a material mixture comprising polycaprolactam and polyethylene can be selectively pyrolyzed in the pyrolysis system 100.

For example, a multicomponent plastic waste material 102 having a polyamide content of about 5 wt.-% or more, preferably of about 7 wt.-% or more, based on the total weight of the multicomponent plastic waste material 102, can be used.

According to a preferred example, the multicomponent plastic waste material 102 may have a polyamide content of about 25 wt.-% or more, for example about 28 wt.-% polycaprolactam, based on the total weight of the multicomponent plastic waste material 102.

The pyrolysis system 100 comprises a first fluidized bed reactor 104 and a second fluidized bed reactor 106.

The polyamide material, for example polycaprolactam, is presently pyrolyzed in a first pyrolysis at a first pyrolysis temperature in the first fluidized bed reactor 104. The first pyrolysis is a preferred example for a first thermal treatment.

The first pyrolysis temperature is presently 240 ° C or more, preferably about 260 ° C or more, in particular about 270 ° C or more. Preferably, the first pyrolysis temperature is about 350 ° C or less, in particular about 325 ° C or less, for example about 310 ° C or less.

In particular for allowing a selective pyrolysis of the polyamide material, a particulate catalyst material 108 is used.

The particulate catalyst material 108 presently forms the bed and is fluidized during the process.

The particulate catalyst material 108 presently consists of a particulate carrier material and a catalytically active material. The carrier material is preferably selected from one or more of the following substances: metal oxides, in particular alumina, for example a (alpha)- alumina, silica, for example fumed silica, carbides, for example silicon carbide, tungsten carbide or mixtures thereof. The catalytically active material is preferably made of a base, in particular an alkali metal oxide, an alkali metal hydroxide, for example potassium hydroxide (KOH) or sodium hydroxide (NaOH) or a mixture thereof, an alkali metal carbonate or a mixture thereof.

The particulate catalyst material 108 comprises about 0.5 wt.-% or more and/or about 22 wt.-% or less of an alkali metal, based on a total weight of the particulate catalyst material 108. For example, the alkali metal is potassium (K) and the alkali metal is part of the catalytically active material of the catalyst material 108.

As carrier material for the particulate catalyst material 108, a material which is essentially non-porous is used.

For example, a particulate catalyst material 108 is used having a BET surface area of about 10 m²/g or less, in particular about 2 m²/g or less. The BET surface area has been determined according to BS ISO 9277:2010; determination of the specific surface area of solids has been performed by gas adsorption.

Due to the presence of the catalyst material 108, the polyamide material, for example polycaprolactam, is depolymerized and reacts to caprolactam at the first pyrolysis temperature during the first pyrolysis.

Due to the small amount of open pores of the catalyst material 108, the polyamide material and the resulting monomer remains on or close to the surface of the catalyst material 108. Thus, transport paths of the polyamide material and the resulting monomer, for example caprolactam, are reduced compared to in a particulate carrier material 108 having a higher amount of open pores.

Furthermore, polymer chains might be too long in order to enter the pores and thus a higher amount of considerable small open pores would lead to less accessible surface area.

The fluidization of the particulate catalyst material 108 ensures that only a thin polyolefin layer around the polyamide material on particles of the catalyst material 108 is formed and/or allows breaking up an already formed layer of polyolefin material by particle collision. The particulate catalyst material 108 is prepared by impregnating the particulate carrier material, preferably with a solution of a catalytically active material. The catalytically active material presently comprises or consists of potassium oxide.

Thus, the particulate catalyst carrier is impregnated with an aqueous potassium hydroxide solution. The solution is obtained by dissolving potassium hydroxide pellets in water. The particulate carrier is impregnated with the potassium hydroxide solution until a maximum intake of the solution has been reached.

The resulting particulate carrier material soaked with solution of catalytically active material is dried, for example, for at about 100 ° C to about 140 ° C for about 2 hours or more (e.g., for about 16 hours). Upon drying, raw particulate catalyst material is formed.

Afterwards, the raw particulate catalyst material is calcined, for example at about 450 ° C to about 550 ° C in air, for example for about 2 hours or more. Preferably, after cooling, for example for about 50 minutes or more, a resulting product is pressed through a separation device to break formed agglomerates. As separation device, preferably a sieve is used. An average mesh size of the separation device is preferably about 200 pm to about 300 pm, for example about 250 pm.

It is assumed, that potassium is present either as oxide, for example as potassium oxide (K₂O), or as a mixed compound between potassium oxide and a carrier-based component (for example K₂O-AI₂O₃ in case the carrier material is made of alumina). Also, hydroxy groups can be present, especially after contact with wet air during storage of the final catalyst material.

Prior to a usage in the process for pyrolyzing the multicomponent plastic waste material 102, the particulate catalyst material 108 used as bed is dried. For example, the particulate catalyst material 108 is heated up to the first pyrolysis temperature, for example in air or dry nitrogen atmosphere.

The average particle size is preferably determined by laser diffraction methods according to DIN ISO 13320, e.g., Beckman Coulter LS 13320 or Malvern Mastersizer 3000). The average particle size is preferably defined as an arithmetic mean of the diameters or diagonals through the particles. Preferably, an average envelope density of particles of the particulate catalyst material is from about 1500 kg/m³ to about 4000 kg/m³, preferably from about 1800 pm to about 3000 kg/m³. The envelope density of the particles is defined as the ratio of the mass of a particle to the sum of the volumes of the solid in each piece and the voids within each piece, that is, within close-fitting imaginary envelopes completely surrounding each piece (ASTM D3766). The ratio of the mass of a particle to the envelope volume of the particle (implied by BSI). The envelope density is preferably determined by mercury pycnometry, e.g., ASTM Standard Test Method C493-93, Bulk Density and Porosity of Granular Refractory Materials by Mercury Displacement.

For example, the following particles were used as particulate catalyst material 108: At ambient conditions, a minimum fluidization velocity of about 0.2 cm/s or more and/or about 40 cm/s or less has been determined. According to the described examples using alpha alumina and/or silicon carbide, the minimum fluidization velocity is about 2 cm/s.

As fluidization gas 110, an inert gas, for example nitrogen, is used. In the alternative or additionally, non-condensable pyrolysis gases can be recirculated.

Preferably, the multicomponent plastic waste material 102 is comminuted in one or more than one steps. For comminution, for example, one or more of the following techniques are used: shredder, cutting mill, ultracentrifugal mill.

On a lab scale, for example, in a first comminution step, the multicomponent plastic waste material 102 is comminuted to a size from about 2.5 mm to about 3.5 mm. In a second comminution step, preferably, the already comminuted multicomponent plastic waste material is further comminuted to a size from about 0.5 mm to about 1.0 mm.

The inventors have observed that multicomponent plastic waste material 102 with an average particle size of about 0.2 mm or more and/or about 4 mm or less is particularly suitable as feedstock material to be fed into the first fluidized bed reactor 104.

For example, the feedstock is fed into the first fluidized bed reactor 104 via a feeding inlet. For example, the feedstock is fed into the first fluidized bed reactor 104 via a pneumatic element. In the alternative or additionally, the feedstock is fed via a solids transport element, e.g., a cooled screw, or liquid transport element, e.g., an extruder or a non-cooled screw.

For filling the comminuted multicomponent plastic waste material 100 into the first fluidized bed reactor 104, the feeding pipe is presently continuously flushed with a fraction of the fluidization gas 110.

In particular on a lab scale, a gas flow rate of the fluidization gas 110 is preferably 1500 Nl/h or lower.

Preferably, the fluidization gas 110 is preheated before entering into the first fluidized bed reactor 104. In a large-scale plant, it might be beneficial if preheated fluidization gas 110 is used, which has been preheated in other process steps. In addition or alternatively, the pyrolysis system 100 can comprise a preheater 107 arranged upstream of the first fluidized bed reactor 104 (cf. Figure 3). The preheater 107 may serve a preheating of the fluidization gas 110.

During the first pyrolysis, preferably the polyolefin material remains in the first fluidized bed reactor 104, wherein the polyamide material is pyrolyzed and a resulting first pyrolysis product fluid 105, for example a first pyrolysis product gas, is removed from the first fluidized bed reactor 104.

The first pyrolysis product fluid 105 as formed during the first pyrolysis is presently transported by the fluidization gas 110 into a first work-up system 112 (cf. Figure 2). The first work-up system 112 is part of the system 100. In the present embodiment, the first pyrolysis product fluid 105 comprises or consists of caprolactam.

After a work-up in the first work-up system 112, virgin quality caprolactam can be obtained.

The first work-up system 112 for example comprises one or more of the following elements: a gas scrubber 114; and/or a hot gas filter 116; and/or a control filter element 118, for example an extraction thimble; and/or a cooling element 120, for example a cooler.

A preferred embodiment of the first work-up system 112 on a lab scale is schematically shown in Figure 2.

The remaining polyolefin material is preferably adhered to the particulate catalyst material 108. In particular, the particulate catalyst material 108 is coated by the polyolefin material and/or embedded in the polyolefin material.

After the first pyrolysis, the particulate catalyst material 108 is partially or completely covered and/or physically connected with the polyolefin material. The thickness of a layer of the polyolefin material should be small enough so that bed agglomerations are avoided but high enough so that as much material as possible can be transported per catalyst material particle. Thus, there is a threshold for the layer thickness.

After the first pyrolysis, the particulate catalyst material 108 and the remaining multicomponent plastic waste material is transferred from the first fluidized bed reactor 104 to the second fluidized bed reactor 106, for example using pneumatic conveying or using gravimetric forces.

In the second fluidized bed reactor 106, a second pyrolysis is performed, wherein the polyolefin material is pyrolyzed, wherein in particular a second pyrolysis product fluid 122 is formed. The second pyrolysis product fluid 122 is presently removed from the second fluidized bed reactor 106. The particulate catalyst material 108 and deposits in the form of solid pyrolysis residues of the second polymer material on the particulate catalyst material remain in the second fluidized bed reactor 106 after the second pyrolysis until reconditioning.

The second pyrolysis is a preferred example for a second thermal treatment.

After the second pyrolysis, the particulate catalyst material 108 can be transferred back from the second fluidized bed reactor 106 to the first fluidized bed reactor 104 and can again be used for pyrolysis.

However, before transferring the particulate catalyst material 108 back to the first fluidized bed reactor 104, it is preferably regenerated by combustion, while heat of the particles may be used as pyrolysis enthalpy for the second pyrolysis.

For regeneration and/or combustion the pyrolysis system 100 preferably comprises a conditioning system 130, which will be described in more detail in connection with Figures 4A, 4B and 4C below.

According to the presently described embodiment, the process is continuous.

The second pyrolysis temperature is preferably about 400 ° C or more, preferably about 475 C or more, in particular about 495 ° C or more and/or about 650 ° C or less, preferably about 600 ° C or less, in particular about 550 ° C or less. In Figure 5, the process during the second pyrolysis is schematically illustrated in a flow chart in more detail.

During the second pyrolysis, presently a second pyrolysis product fluid 122 is formed, which is transported by the fluidization gas 110 into a second work-up system 124.

Although in the present example, the same fluidization gas is used for the first pyrolysis and the second pyrolysis, in the alternative, it is possible to use different fluidization gases for the first pyrolysis and the second pyrolysis and/or to generate process heat and/or electricity.

As can be seen in particular in Figure 5, the second work-up system 124 may comprise a condenser element 125 for condensing pyrolysis oil 126 from the second pyrolysis product fluid 122 and separating the pyrolysis oil 126 from permanent gases of in the second pyrolysis product fluid 122. In Figure 5, the incoming mixture of particulate catalyst material and remaining multicomponent plastic waste material after the first pyrolysis is indicated by an arrow in the direction of the second fluidized bed reactor 106. The permanent gases are indicated by a dotted arrow pointing away from the condenser element 125.

The pyrolysis oil 126 comprises or consists of pyrolysis products of the polyolefin material 127, for example cracked polyolefin.

According to the presently described embodiment, the resulting pyrolysis oil 126 has a nitrogen content that is about 85 % or more, preferably about 90 % or more, smaller than the nitrogen content of the original multicomponent plastic waste material 102.

The nitrogen content of the pyrolysis oil is preferably determined by chemiluminescence methods. A sample to be analyzed is diluted (if needed) and an aliquot is combusted in the instrument at about 1000 ° C under argon and oxygen atmosphere. The detection is performed via chemiluminescence. This method is a modification of DIN 51444:2020-10. This method is used for nitrogen concentrations up to ca. 0.5 g/100 g.

If a nitrogen concentration is above 0.5 g/100 g, the sample (1 mg to 10 mg) to be analyzed is combusted in a helium or oxygen atmosphere and resulting NOx is subsequently reduced to nitrogen. After separation of the combustion gases, the nitrogen concentration is determined and quantified as N2 via thermal conductivity. As elemental analyzer Elementar, model Vario EL Cube can be used.

The nitrogen content in the multicomponent polymer material is determined according Kjeldahl digestion and water steam distillation. A sample to be analyzed is digested with concentrated sulfuric acid and a catalyst according to Kjeldahl, all nitrogen species are converted into ammonium sulfate after digestion. Sodium hydroxide is added to the digest, and ammonia is transferred into a receiving solution by means of water steam distillation. The final determination is performed by means of photometry or ion chromatography. This method is used for nitrogen concentration up to about 0.5 g/100 g.

In Figure 2, an embodiment of the first pyrolysis on a lab scale is schematically shown in more detail and its operation illustrated in Figure 3.

As described in connection with Figure 1, the polyamide material is pyrolyzed in the first fluidized bed reactor 104, using the particulate catalyst material 108 as bed. In this regard, it is referred to the description above.

As can be seen from Figures 2 and 3, after passing through a hot gas filter 116 of the first work-up system 112, condensable and soluble components of the first pyrolysis product fluid 105 are separated from off-gas in a separation system 128. The separation system 128 is part of the first work-up system 112. The separation system 128 on a lab scale presently comprises or consists of two gas scrubbers 114 and a cooler 120. The two gas scrubbers 114 are preferably operated in sequence.

In addition or in the alternative to a hot gas filter 116 one or more cyclones can be used.

On a lab scale, presently, after the first pyrolysis, samples are taken and analyzed in a characterization device 115, for example a flame ionization detector (FID). The gas scrubbers 114 are presently water-cooled and operated at about 20 ° C to about 40 ° C. Presently, both gas scrubbers are filled with o-Xylol.

From both gas scrubbers 114, a resulting decomposition product is obtained (indicated by arrows). However, as indicated by a dotted line, one of the gas scrubbers 114 can be bypassed.

Off-gas is cooled by a cooler 120 which is operated at a temperature slightly below the melting point of the first polymer material in order to obtain a liquid product (here: caprolactam) and to avoid crystallization.

For embodiments, in which polycaprolactam is used as polyamide material, a conversion rate of polycaprolactam to caprolactam of 85 % or more can be reached.

As is schematically shown in the flow chart depicted in Figure 4, the pyrolysis system 100 presently comprises a conditioning system 130 for adjusting the temperature of the fluidization gas 110 or for regenerating the catalyst material 108. The conditioning system 130 is in the presently described example a part of the pyrolysis system 100 and used for startup, shutdown and regeneration of the particulate catalyst material 108.

In particular for regeneration of the catalyst material 108, the fluidization gas 110 comprises air or air and non-condensable pyrolysis gases from one or both of the pyrolysis reactors. In latter case the non-condensable pyrolysis gases are oxidized together with the material remaining on the catalyst material 108. For example, formed pyrolysis char is combusted.

As already mentioned, the conditioning system 130 is shown in more detail in Figures 4A, 4B and 4C.

According to preferred embodiments, the conditioning system 130 can be integrated into the second fluidized bed reactor 106 (cf. Figures 4A and 4C) or the conditioning system 130 can include a regeneration unit 134, e.g., a regeneration reactor, which is spaced apart from the second fluidized bed reactor 106 (cf. Figure 4B).

As shown in Figure 4A, the pyrolysis system 100 preferably includes a heat transfer device 132 for heat transfer between the first fluidized bed reactor 104 and the second fluidized bed reactor 106. The heat transfer device 132 in particular provides an indirect thermal coupling of the first fluidized bed reactor 104 and the second fluidized bed reactor 106.

For example, excess heat generated within the second fluidized bed reactor 106 can be dissipated or transferred for further use via the heat transfer device 132 as indicated by a dotted arrow in Figure 4A.

For regeneration of the particulate catalyst material 108 lean air 135 (i.e., air having an oxygen content which is lower than the oxygen content of normal breathing air/ambient air) is introduced into the second fluidized bed reactor 106 as fluidization gas 110. The lean air 135 is preferably introduced from a lower end of the second fluidized bed reactor 106. The lean air 135 is illustrated as a dot-dashed arrow in Figure 4A.

For regeneration and/or reconditioning of the particulate catalyst material 108, preferably, the fluidization gas 110 (which may contain air in an amount of about 0 wt.-% to about 100 wt.-%) reaches a regeneration temperature of about 600 to 900 ° C, preferably about 900

C or less. On a lab scale, the regeneration temperature is reached via additional heating. On a large scale, the regeneration temperature is reached basically intrinsically due to the enthalpy of combustion of the solid pyrolysis residue.

In Figure 4C, a more detailed example of a pyrolysis system 100, in which the conditioning system 130 is integrated into the second fluidized bed reactor 106 is schematically shown.

According to this example, the polyamide material is pyrolyzed in the first fluidized bed reactor 104 as described above, for example at about 280 ° C to about 320 ° C.

During the first pyrolysis, the polyolefin material is deposited around the particles of the particulate catalyst material 108. After the first pyrolysis, the particulate catalyst material 108 and the polyolefin material 127 are transferred from the first fluidized bed reactor 104 to the second fluidized bed reactor 106, presently via a first transfer line 136. The first transfer line 136 preferably connects an upper area of the first fluidized bed reactor 104 with an upper end of the second fluidized bed reactor 106.

“Upper” is the area or end which is opposite to the area or the end on which the fluidization gas 110 is introduced. The pyrolysis system 100 presently includes a heat transfer device 132, for example a heat transfer tube, which connects the first transfer line 136 with the upper end of the second fluidized bed reactor 106. The heat transfer device 132 protrudes into the second fluidized bed reactor in a direction of the inlet of the fluidization gas 110 but being spaced apart from the inlet of the fluidization gas.

The particulate catalyst material 108 and the polyolefin material 127 are introduced into the second fluidized bed reactor 106 in a direction of flow which is basically opposite to the main direction of flow of the fluidization gas 110.

The heat transfer device encloses an inner space which during operation presently is part of a pyrolysis zone 138. The heat transfer device 132 presently is enclosed by an outer space. In the outer zone, the main direction of flow of the particulate catalyst material 108, during operation, is countercurrent to the main direction of flow of the particulate catalyst material 108 in the outer space.

The pyrolysis zone 138 is the area inside the second fluidized bed reactor 106 in which the pyrolysis of the polyolefin material takes place. Presently, the pyrolysis zone 138 is in the center of the second fluidized bed reactor 106. In radial directions regarding a central axis of the second fluidized bed reactor 106, the pyrolysis zone 138 is limited by the walls of the heat transfer device 132. The heat transfer device 132 presently comprises a heat transfer zone in which heat is transferred from particles in radially outward areas of the pyrolysis zone 138 to particles in the pyrolysis zone 138 of the second fluidized bed reactor 106.

Due to the heat transfer, the catalyst material 108 is cooled down from about 550 ° C to about 350 ° C.

On the end which is opposite to the end on which the catalyst material 108 and the polyolefin material 127 are introduced to the second fluidized bed reactor 106, a combustion zone 140 is arranged within the second fluidized bed reactor 106 during operation.

Within the combustion zone 140, the temperature is about 10% or more higher than in the pyrolysis zone 138. In the combustion zone 140, deposits on particles of the catalyst material 108 are combusted. Since lean air 135 is used as fluidization gas 110, the oxygen content is only high enough for oxidation in the combustion zone 140, while in the pyrolysis zone 138, essentially no oxygen is left. Thus, the catalyst material 108 is regenerated only in the combustion zone 140.

After the regeneration, the particulate catalyst material 108 is transported upwards by the fluidization gas 110.

The catalyst material 108 which has been cooled down in the heat transfer zone and regenerated in the combustion zone 140, is transferred from the second fluidized bed reactor 106 to the first fluidized bed reactor 104 via a second transfer line 144.

The first transfer line 136 and/or the second transfer line 144 preferably include a gas blocking element for blocking and/or reducing a gas exchange between the first fluidized bed reactor 104 and the second fluidized bed reactor 106 (not graphically shown).

In addition or in the alternative to gas blocking elements in the first transfer line 136 and/or the second transfer line 144, the first fluidized bed reactor 104 and/or the second fluidized bed reactor 106 may include a gas blocking element in the areas in which material is introduced or removed from the respective reactor.

Preferred examples for a gas blocking element are the following: an element for controlling the recirculation mass flow of the catalyst material 108 or the catalyst material 108 with the remaining polyolefin material 127 from the first fluidized bed reactor 104 to the second fluidized bed reactor 106 and vice versa, e.g., a valve; a gas sealing element.

Preferred valves, which act also as sealing elements are mechanical valves, non-mechanical valves, e.g., L-valves or loop seals.

The valves and or sealing elements may be used with or without aeration in order to avoid contamination of material in either reactor. Inert gas may also be used in order to avoid contamination of the content of the first reactor and the second reactor.

Even without an additional gas flow, at least partially, a gas tightness between the first reactor and the second reactor is obtained due to pressure loss of the bulk material, e.g., in an L-valve. If additional gas tightness is desired, gas, e.g., inert gas, can be used countercurrent to the direction of flow of the bulk material.

Flue gas and the second pyrolysis product fluid 122 are discharged at an upper end of the second fluidized bed reactor 106 (indicated via arrows).

Although not further described, also the embodiments depicted in Figures 4A and 4B preferably include a first and a second transfer line.

In Figure 4B, an embodiment of the pyrolysis system 100 is schematically shown, in which the conditioning system 130 comprises a regeneration unit 134 which is spatially separate from the second fluidized bed reactor 106.

The pyrolysis system 100 basically corresponds to the pyrolysis system 100 of Figure 4A, but the pyrolysis system 100 further comprises a regeneration unit 134 which is thermally and fluidical ly coupled with the second fluidized bed reactor 106. After the second pyrolysis, the hot particulate catalyst material 108 containing residues of the multicomponent plastic material 102 is transferred to the regeneration unit 134. Air is introduced to the regeneration unit 134 and the catalyst material 108 is regenerated while residues are combusted.

Excess heat which is generated during the regeneration can be decoupled (indicated by the dotted line in Figure 4b).

The conditioning system 130 may also comprise a waste heat boiler 142 from which flue gas and heat (dotted arrow) are discharged. The heat from the waste heat boiler can be used to produce steam.

The pyrolysis system 100 including the first fluidized bed reactor 104, the second fluidized bed reactor 106 and the conditioning system 130 is preferably operated autothermally.

After regeneration, the particulate catalyst material 108 can again be used as bed in the first pyrolysis.

With the process and/or the pyrolysis system 100 as described above, a selective pyrolysis can be performed.

Claims

1. Process for thermal treatment of a multicomponent plastic waste material (102), comprising: providing a multicomponent plastic waste material (102), including a first polymer material and a second polymer material; treating the first polymer material in a first thermal treatment in a first reactor (104) at a first temperature wherein the first thermal treatment is a first pyrolysis and the first polymer material is pyrolyzed at the first pyrolysis temperature; and treating the second polymer material in a second thermal treatment in a second reactor (106) at a second temperature, which is higher than the first temperature wherein the second thermal treatment is a second pyrolysis and the second polymer material is pyrolyzed in the second pyrolysis at the second pyrolysis temperature.

2. Process according to claim 1, wherein the first thermal treatment is a first pyrolysis, the first temperature is a first pyrolysis temperature and a catalyst material (108) is used; and wherein the second thermal treatment is a second pyrolysis and the second temperature is a second pyrolysis temperature.

3. Process according to claim 1 or 2, wherein the first reactor is a first fluidized bed reactor (104); and a particulate catalyst material is used; and/or wherein the second reactor is a second fluidized bed reactor.

4. Process according to any one of claims 1 to 3, wherein the process is a continuous process and wherein preferably the first reactor (104) and the second reactor (106) are mechanically and/or fluidical ly coupled.

5. Process according to any one of claims 1 to 4, wherein the first temperature is 200 ° C or more, preferably about 225 ° C or more, in particular about 245 ° C or more, for example about 270 ° C or more, and/or about 350 ° C or less, preferably about 325

C or less, for example about 310 ° C or less.

6. Process according to any one of claims 3 to 5, wherein the particulate catalyst material (108) consists of or comprises a carrier material and a catalytically active material, wherein preferably the carrier material is selected from one or more of the following substances: metal oxides, in particular alumina, for example a (alpha)- alumina, silica, for example fumed silica, carbides, for example silicon carbide, tungsten carbide or mixtures thereof and/or wherein preferably the catalytically active material is made from a base, in particular an alkali metal oxide, an alkali metal hydroxide, for example potassium hydroxide (KOH) or sodium hydroxide (NaOH) or a mixture thereof, an alkali metal carbonate or a mixture thereof.

7. Process according to any one of claims 3 to 6, wherein the particulate catalyst material (108) comprises about 0.5 wt.-% or more and/or about 22 wt.-% or less of an alkali metal, based on a total weight of the particulate catalyst material, wherein preferably the alkali metal is potassium (K) and wherein the alkali metal is part of a catalytically active material of the particulate catalyst material (108).

8. Process according to any one of claims 3 to 7, wherein in the first fluidized bed reactor (104) the particulate catalyst material (108) and the multicomponent plastic waste material (102) are used in a weight ratio from about 3:1 to about 25:1, preferably about 3:1 to about 5:1, and/or wherein during the first pyrolysis, a first pyrolysis product fluid (105) is formed, which is transported by a fluidization gas (110) into a first work-up system (112).

9. Process according to any one of claims 1 to 8, wherein after the first thermal treatment, a particulate catalyst material (108) is partially or completely covered and/or physically connected with the second polymer material.

10. Process according to any one of claims 3 to 9, wherein after the first pyrolysis, the particulate catalyst material (108) and remaining multicomponent plastic waste material, in particular molten polyolefin material, are transported from the first fluidized bed reactor (104) into the second fluidized bed reactor (106), preferably using gravimetric forces or pneumatically.

11. Process according to any one of claims 1 to 10, wherein the second temperature is about 400 ° C or more, preferably about 475 ° C or more, in particular about 495 ° C or more, and/or about 650 ° C or less, preferably about 600 ° C or less, in particular about 550 ° C or less.

12. Process according to any one of claims 2 to 11, wherein the catalyst material is a particulate catalyst material (108) and wherein after the second pyrolysis, the particulate catalyst material (108) is reconditioned in a conditioning system (130) by combusting deposits, for example pyrolysis char, wherein the conditioning system (130) preferably comprises a separate regeneration unit (134) or is part of the second fluidized bed reactor (104) and/or wherein a pyrolysis system (100) including the conditioning system (130) is operated autothermally.

13. Process according to any one of claims 1 to 12, wherein the first polymer material comprises or consists of one or more of the following: a polyamide material, in particular aliphatic polyamides, for example polycaprolactam, or copolymers or mixtures thereof, polyvinyl chloride, polystyrene, polybutylene terephthalate, polycarbonate, and/or wherein the second polymer material comprises or consists of a polyolefin material, in particular polyethylene, polypropylene, polybutene or mixtures thereof, wherein preferably the first polymer material is a polyamide material and the second polymer material is a polyolefin material.

14. Thermal treatment system (100) for thermally treating a multicomponent plastic waste material (102), in particular for thermal treatment of a multicomponent plastic waste material (102) in a process according to any one of claims 1 to 13, comprising: a first reactor (104) for thermal treatment of a first polymer material in a first thermal treatment at a first temperature; and a second reactor (106) for thermal treatment of a second polymer material in a second thermal treatment at a second temperature.

15. Use of a particulate catalyst material (108) in a process for thermal treatment of a multicomponent plastic waste material (102), in particular in a process according to any one of claims 1 to 13, wherein the particulate catalyst material (108) has a BET surface area of about 25 m²/g or less, determined according to BS ISO 9277:2010.

16. Process, preferably according to any one of claims 1 to 13, wherein the process comprises the step: converting the first pyrolysis product fluid (105) and/or polyamide monomer and/or the second pyrolysis product fluid (122) obtainable by or obtained by the process according to any one of claims 1 to 13 from the first pyrolysis and/or from the second pyrolysis or a chemical material obtainable by or obtained by the process according to any one of claims 1 to 13 to obtain a monomer, polymer or polymer product. Process comprising the step: using the thermal treatment system according to claim 13 to obtain a purified pyrolysis oil, monomer, polymer or polymer product. Process according to any one of claims 1 to 13, 16 and 17, wherein the monomer is a di- or polyol; preferably butandiol; aldehyde; preferably formaldehyde; di- or polyisocyanate; preferably methylene diphenyl diisocyanate (MDI), polymeric methylene diphenyl diisocyanate (pMDI), toluene diisocyanate (TDI), hexamethylenediisocyanate (HDI) or isophoronediisocyanate (IPDI); amide; preferably caprolactam; alkene; preferably styrene, ethene and norbornene; alkyne, (di)ester; preferably methyl methacrylate; mono or diacid; preferably adipic acid or terephthalic acid; diamine; preferably hexamethylenediamine, nonanediamine; or sulfones; preferably 4,4'-dich lorodi phenyl sulfone. Process according to any one of claims 1 to 13 and 16 to 18, wherein the polymer is and/or the polymer product comprises polyamide (PA); preferably PA 6 or PA 66; polyisocyanate polyaddition product; preferably polyurethane (PU), thermoplastic polyurethane (TPU), polyurea or polyisocyanurate (PIR); low-density polyethylene (LDPE), high-density polyethylene (HDPE), polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC), polyvinyl acetate (PVA), polystyrene (PS), poly acrylonitrile butadiene styrene (ABS), poly styrene acrylonitrile (SAN), poly acrylate styrene acrylonitrile (ASA), polytetrafluoroethylene (PTFE), poly(methyl acrylate) (PMA), poly(methyl methacrylate) (PMMA), polybutadiene (BR, PBD), poly(cis-l,4-isoprene), poly(trans-l,4-isoprene), polyoxymethylene (POM), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polybutylene adipate coterephthalate (PBAT), polyester (PES), polyether sulfone (PESU), polyhydroxyalkanoate (PHA), poly-3-hydroxybutyrate (P3HB), poly-4-hydroxybutyrate (P4HB), polyhydroxyvalerate (PHV), polyhydroxyhexanoate (PHH), polyhydroxyoctanoate (PHO), polylactic acid (PLA), polysulfone (PSU), polyphenylene sulfone (PPSU), polycarbonate (PC), polyether ether ketone (PEEK), poly(p-phenylene oxide) (PPO), poly(p-phenylene ether) (PPE); or copolymer or mixture thereof; preferably polyamide (PA); more preferably PA 6.

20. Process according to any one of claims 1 to 13 and 16 to 19, wherein the polymer and/or the polymer product is/are or is/are a part of: a part of a car; preferably cylinder head cover, engine cover, housing for charge air cooler, charge air cooler flap, intake pipe, intake manifold, connector, gear wheel, fan wheel, cooling water box, housing, housing part for heat exchanger, coolant cooler, charge air cooler, thermostat, water pump, radiator, fastening part, part of battery system for electromobility, dashboard, steering column switch, seat, headrest, center console, transmission component, door module, A, B, C or D pillar cover, spoiler, door handle, exterior mirror, windscreen wiper, windscreen wiper protection housing, decorative grill, cover strip, roof rail, window frame, sunroof frame, antenna panel, headlight and taillight, engine cover, cylinder head cover, intake manifold, airbag, cushion, or coating; a cloth; preferably shirt, trousers, pullover, boot, shoe, shoe sole, tight or jacket; an electrical part; preferably electrical or electronic passive or active component, circuit board, printed circuit board, housing component, foil, line, switch, plug, socket, distributor, relay, resistor, capacitor, inductor, bobbin, lamp, diode, LED, transistor, connector, regulator, integrated circuit (IC), processor, controller, memory, sensor, microswitch, microbutton, semiconductor, reflector housing for light-emitting diodes (LED), fastener for electrical or electronic component, spacer, bolt, strip, slide-in guide, screw, nut, film hinge, snap hook (snap-in), or spring tongue; a consumer, agricultural product or pharmaceutical product; preferably tennis string, climbing rope, bristle, brush, artificial grass, 3D printing filament, grass trimmer, zipper, hook and loop fastener, paper machine clothing, extrusion coating, fishing line, fishing net, offshore line and rope, vial, syringe, ampoule, bottle, sliding element, spindle nut, chain conveyor, plain bearing, roller, wheel, gear, roller, ring gear, screw and spring dampers, hose, pipeline, cable sheathing, socket, switch, cable tie, fan wheel, carpet, box or bottle for cosmetics, mattress, cushion, insulation, detergent, dishwasher tabs or powder, shampoo, body wash, shower gel, soap, fertilizer, fungicide, or pesticide; a packaging for the food industry; preferably mono- or multi-layer blown film, cast film (mono- or multi-layer), biaxially stretched film, or laminating film; or a part of a construction; preferably a rotor blade, insulating material, frame, housing, wall, coating, or separating wall. Process according to any one of claims 1 to 13 and 16 to 20 wherein the content of the multicomponent plastic waste material (102) in the monomer, polymer and/or polymer product is 1 weight-% or more, preferably 2 weight- % or more, more preferably 5 weight-% or more, more preferably 15 weight-% or more, more preferably 30 weight-% or more, more preferably 40 weight-% or more, more preferably 60 weight-% or more, more preferably 80 weight-% or more, more preferably 90 weight-% or more, more preferably 95 weight-% or more; and/or wherein the content of the multicomponent plastic waste material (102) in the monomer, polymer and/or polymer product is 100 weight-% or less, preferably 95 weight-% or less, more preferably 90 weight-% or less, more preferably 50 weight-% or less, more preferably 25 weight-% or less, more preferably 10 weight-% or less; and preferably wherein the content is determined based on identity preservation and/or segregation and/or mass balance and/or book and claim chain of custody models, preferably based on mass balance, preferably the International Sustainability and Carbon Certification (ISCC) standard.