Chemical plant and method for separating a steam cracker feedstock from a feedstock stream comprising at least one plastic pyrolysis oil

Abstract

The present invention relates to a method and a chemical plant for a steam cracker feedstock from a feedstock stream comprising at least one plastic pyrolysis oil. The method comprises the steps a) evaporating the feedstock, b) removing olefins and dienes from the evaporated feedstock by a first hydrotreatment, c) further heating the hydrotreated product stream, d) removing heteroatoms from the hydrotreated product stream by a second hydrotreatment, d) continuously or discontinuously feeding a washing water stream to the hydrotreated product stream after the second hydrotreatment, e) condensing the hydrotreated product stream, f) separating the hydrotreated product stream from a recycle stream and optionally from the washing water stream. The method and chemical plant prevent undesired polymerization of components in the feedstock stream and thereby undesired fouling is suppressed.

Description

[0001] Chemical plant and method for separating a steam cracker feedstock from a feedstock stream comprising at least one plastic pyrolysis oil

[0002] Technical Area

[0003] The present invention relates to a method and a chemical plant for separating a steam cracker feedstock from a feedstock stream comprising at least one plastic pyrolysis oil.

[0004] Background of the invention

[0005] A method for processing a plastic pyrolysis oil comprising the steps a) selective hydrogenation, b) hydroprocessing and c) separation of the hydroprocessed effluent is disclosed in AU 2021 / 222788 A1 . At least a portion of the hydroprocessed effluent obtained after the separation in step c) is recycled into the a) selective hydrogenation and / or b) the hydroprocessing. The selective hydrogenation (step b)) at temperatures of up to 250 °C (i.e. , mostly in the liquid phase) can result in undesired polymerization of feedstock potions inside the hydrogenation unit. Furthermore, a separation step after a selective hydrogenation a) and a hydroprocessing b) requires a larger and therefore more expensive hydroprocessing unit because the whole hydrotreated stream obtained in step a) is subjected to the hydroprocessing of step b). In addition, the consumption of H2 is very high of the same reason. The second hydroprocessing is operated in the gas-phase including recycle-gas operation. This method is directed to produce a steam cracking feedstock. A method of this type is shown in figure 1 which also represents the comparative example below.

[0006] Document WO 2021 / 204820 A1 discloses a process for the purification of a feedstock stream comprising a pyrolysis oil. The process comprises a single hydroprocessing step at a temperature of at least 230 °C in the presence of hydrogen. Dienic and other polymerizable components present in the pyrolysis oil when entering the hydroprocessing unit at such a high process temperature causes undesired polymerization of said components which then leads to undesired foiling inside the hydroprocessing unit.

[0007] US2023 / 287282A1 discloses a process for the purification of a hydrocarbon stream in which a single hydroprocessing step is performed at a temperature of at least 250 °C. The resulting purified hydrocarbon stream is suited as a feedstock for steam cracking.

[0008] FR3118629A1 (AU2021411704A1 ) discloses a method including a hydrogenation step for treating plastic pyrolysis oils. The method comprises two successive hydrotreatment steps followed by a separation step in which the hydrotreated plastic pyrolysis oil is combined with an aqueous solution and then separated into at least one gaseous effluent and a hydrocarbon-based effluent. The hydrocarbon-based effluent or a portion thereof is then optionally fractionated.

[0009] A process for hydroprocessing a liquid feed comprising hydrocarbons into fuel components is disclosed in EP2792729A1 . The resulting products can be used as fuels and a feedstock for naphtha crackers. Separating C6-C8 aromatic hydrocarbons from a feedstock stream comprising at least one plastic pyrolysis oil is not disclosed in this document.

[0010] It is an objective of the present invention to provide a method and a chemical plant for separating a steam cracker feedstock stream from a liquid stream comprising at least one plastic pyrolysis oil which was obtained by pyrolysis of plastic waste. Furthermore, the method and chemical plant should decrease undesired fouling during processing when separating a steam cracker feedstock stream liquid stream comprising at least one plastic pyrolysis oil which was obtained by pyrolysis of plastic waste.

[0011] Summary of the Invention

[0012] These problems are solved by a method for separating a steam cracker feedstock from a feedstock stream comprising at least one plastic pyrolysis oil, the method comprising the steps

[0013] (i) providing a liquid stream S1 comprising at least one plastic pyrolysis oil, the liquid stream S1 further comprising organic compounds comprising at least one heteroatom and compounds comprising C-C double and / or C-C triple bonds,

[0014] (ii) providing a stream S2, the stream S2 comprising hydrogen,

[0015] (iii) evaporating at least a portion of the liquid stream S1 in the presence of the stream S2 and a recycle gas stream S11 in an evaporation unit EU and thereby forming a gaseous stream S3 which comprises the evaporated portion of the liquid stream S1 , and a liquid stream S4 which comprises the portion of liquid stream S1 which is not evaporated in the evaporation unit EU,

[0016] (iv) optionally superheating the gaseous stream S3 in a superheater SH and thereby form a superheated stream S5,

[0017] (v) feeding the gaseous stream S3 or, optionally the superheated stream S5 into a first hydrogenation unit HU1 in which at least a portion of the gaseous stream S3 or, optionally at least a portion of the superheated stream S5 is converted into a stream S6, wherein the stream S6 is depleted in compounds comprising C-C double and / or C-C triple bonds in respect to gaseous stream S3,

[0018] (vi) heating the gaseous stream S6 in at least one heating device HD and thereby forming a heated gaseous stream S7,

[0019] (vii) subjecting the heated gaseous stream S7 to a second hydrogenation unit HU2 in which a product stream S8 is formed, wherein the product stream S8 is depleted in organic compounds comprising at least one heteroatom in respect to gaseous stream S6,

[0020] (viii) optionally transferring heat from the product stream S8 to the gaseous stream S3 in the superheater SH and thereby forming a cooled down product stream S8b,

[0021] (ix) continuously or discontinuously feeding a washing water stream S15 to the product stream S8 and thereby forming a stream comprising washing water S8a or optionally continuously or discontinuously feeding a washing water stream S15 to the cooled down product stream S8b and thereby forming a cooled down product stream optionally comprising washing water S8c, (x) optionally transferring heat from the cooled down product stream comprising washing water S8c to the liquid stream S1 , stream S2 and stream S11 in the evaporation unit EU and thereby forming a further cooled down product stream S8d,

[0022] (xi) condensing the product stream comprising washing water S8a or optionally one of the streams selected from the group consisting of the cooled down product stream S8b, the cooled down product stream optionally comprising washing water S8c, and the further cooled down product stream optionally comprising washing water S8d, in a condensation unit CU and thereby forming a product stream S9, wherein the product stream S9 comprises a liquid phase and a gas phase,

[0023] (xii) separating the liquid product stream S9 in a separation unit SU into a liquid product stream S10, a recycle gas stream S11 and optionally a waste water stream S17 wherein the recycle gas stream S11 comprises hydrogen and wherein at least a portion of the recycle gas stream S11 is fed into the evaporation unit EU,

[0024] (xiii) optionally feeding the refined product stream S10 into a distillation unit DU in which the liquid product stream S10 is separated into a stabilized product stream S12 and a gaseous stream S13 and

[0025] (xiv) optionally converting stream S12 by steam cracking into a C2-C4 olefin and / or converting stream S4 by a partial oxidation reaction into a mixture of CO and H2 and optionally separate said CO and said H2.

[0026] These problems are further solved by a chemical plant for separating a steam cracker feedstock from a feedstock stream comprising at least one plastic pyrolysis oil, the chemical plant comprising

[0027] (i) an evaporation unit EU,

[0028] (ii) optionally a superheater SH downstream of the evaporation unit EU,

[0029] (iii) a first hydroprocessing unit HU1, the first hydroprocessing unit HU1 comprising at least one inlet and at least one outlet, the first hydroprocessing unit HU1 downstream of the evaporation unit EU or the optional superheater SH and the at least one inlet of the first hydroprocessing unit HU1 fluidically connected to the evaporation unit EU or the optional superheater SH,

[0030] (iv) a heating unit HD having at least one inlet and at least one outlet, the heating unit HD downstream of and at least one inlet of the heating unit HD fluidically connected to the at least one outlet of the first hydroprocessing unit HU1,

[0031] (v) a second hydroprocessing unit HU2 having at least one inlet and at least one outlet, the second hydroprocessing unit HU2 downstream of the heating unit HD and the at least one inlet of the hydroprocessing unit HU2 fluidically connected to the at least one outlet of the heating device HD,

[0032] (vi) a condensation unit CU having at least one inlet and at least one outlet, the condensation unit CU downstream of the second hydroprocessing unit HU2 and the at least one inlet of the condensation unit CU fluidically connected to the at least one outlet of the second hydroprocessing unit HU2,

[0033] (vii) a separation unit SU having at least one inlet and at least one outlet, the separation unit SU downstream of and the at least one inlet of the separation unit SU fluidically connected to the at least one outlet of the condensation unit CU and

[0034] (viii) optionally a distillation unit DU comprising at least one inlet and at least one outlet which is a head outlet, the optional distillation unit DU downstream of and the at least one inlet of the optional distillation unit DU fluidical- ly connected to the at least one outlet of the separation unit SU, optionally a steam cracking unit SCU, downstream of and fluidically connected to the at least one head outlet of the optional distillation unit DU.

[0035] Figure 1 shows a method in which a liquid recycle stream from a second hydroprocessing unit into a first hydroprocessing unit is utilized. Such a recycle stream is employed in the method disclosed in AU 2021 / 222788 A1 and was used therefore as comparative example below.

[0036] Figure 2 shows the method and the chemical plant for separating steam cracker feedstock from a feedstock stream comprising at least one plastic pyrolysis oil according to the present invention.

[0037] Figure 3 shows the method and the chemical plant for separating a steam cracker feedstock from a feedstock stream comprising at least one plastic pyrolysis oil according to the present invention including an optional superheater SU and optional step (iv).

[0038] Figure 4 shows the method and the chemical plant for separating a steam cracker feedstock from a feedstock stream comprising at least one plastic pyrolysis oil according to the present invention including optional steps (iv), (viii) and (x).

[0039] Detailed description of the invention

[0040] The present invention is further described below with reference to the embodiments, but the present invention is not limited to these embodiments, and any modifications of these embodiments, combinations of these embodiments or substitutions within the basic spirit of the present invention are still within the scope of the present invention as claimed.

[0041] Definitions:

[0042] In the context of the present description and the accompanying claims, the term "about” preferably means a deviation of the thus described value of ±10 %. In the context of the present invention, the term “combinations thereof' is inclusive of one or more of the recited elements. In the context of the present invention, the term “mixture thereof” is inclusive of one or more of the recited elements.

[0043] In the context of the present invention, the term “pyrolysis” relates to a thermal decomposition or degradation of a feedstock such as plastic waste under inert conditions and results in a gas, a liquid, and a solid char fraction. During the pyrolysis, the feedstock is converted in a pyrolysis unit into a great variety of chemicals including gases such as H2, Ci- to C4-alkanes, C2- to C4-alkenes, ethyne, propyne, 1 -butyne, plastic pyrolysis oil having a boiling temperature of 25 °C to 500 °C and char. In addition, water is formed during the pyrolysis which may be partially dispersed in the plastic pyrolysis oil and may be partially contacted with the plastic pyrolysis oil in a separate phase. The water formed during pyrolysis comprises various organic compounds and / or salts thereof which were also formed during the pyrolysis. The term “pyrolysis” includes slow pyrolysis, fast pyrolysis, flash catalysis and catalytic pyrolysis. These pyrolysis types differ regarding process temperature, heating rate, residence time, feed particle size, etc. resulting in different product quality. The pyrolysis unit may be operated adiabatically, isothermally, nonadiabatically, non- isothermal ly, or combinations thereof. The pyrolysis reactions of this disclosure may be carried out in a single stage or in multiple stages. For example, the pyrolysis unit can comprise two reactor vessels fluidly connected in series.

[0044] In the context of the present invention, the term "plastic pyrolysis oil” is understood to mean any oil originating from the pyrolysis of plastic waste. The term "plastic waste” includes rubber waste such as end-of-life tires and feedstocks comprising plastic waste. The plastic pyrolysis oil is obtained and / or obtainable from pyrolysis such plastic waste.

[0045] In the context of the present invention, the term "plastic waste” refers to any plastic material discarded after use, i.e. , the plastic material has reached the end of its useful life and is considered post-consumer waste. The plastic waste can be pure polymeric plastic waste, mixed plastic waste or film waste, including soiling, adhesive materials, fillers, residues etc. The plastic waste may have an oxygen content, a nitrogen content, sulfur content, halogen content and optionally also a heavy metal content. The plastic waste can originate from any plastic material containing source.

[0046] Accordingly, the term "plastic waste” includes industrial and domestic plastic waste and including used tires and agricultural and horticultural plastic material.

[0047] Typically, plastic waste is a mixture of different plastic materials, including hydrocarbon plastics, e.g., polyolefins such as polyethylene (HDPE, LDPE) and polypropylene, polystyrene, and copolymers thereof, etc., and polymers composed of carbon, hydrogen, and other elements such as chlorine, fluorine, oxygen, nitrogen, sulfur, silicone, etc., for example chlorinated plastics, such as polyvinylchloride (PVC), polyvinylidene chloride (PVDC), etc., nitrogencontaining plastics, such as polyamides (PA), polyurethanes (PU), acrylonitrile butadiene styrene (ABS), etc., oxy- gen-containing plastics such as polyesters, e.g., polyethylene terephthalate (PET), polycarbonate (PC), etc., silicones and / or sulfur bridges crosslinked rubbers.

[0048] Typically, the plastic material comprises additives, such as processing aids, plasticizers, flame retardants, pigments, light stabilizers, lubricants, impact modifiers, antistatic agents, antioxidants, etc. These additives may comprise elements other than carbon and hydrogen. For example, bromine is mainly found in connection to flame retardants. Heavy metal compounds may be used as lightfast pigments and / or stabilizers in plastics. Cadmium, zinc, and lead may be present in heat stabilizers and slip agents used in plastics manufacturing. The plastic waste can also contain residues. Residues in the sense of the invention are contaminants adhering to the plastic waste. The additives and residues are usually present in an amount of less than 50 wt.-%, preferably less than 30 wt.-%, more preferably less than 20 wt.-%, even more preferably less than 10 wt.-%, based on the total weight of the dry weight plastic.

[0049] Examples of rubber waste (which is also considered "plastic waste” in the sense of the present invention) include end-of-life tires, rubber waste produced during manufacturing processes and discarded rubber containing products such as latex examining gloves and gaskets. End-of-life tires comprise further ingredients such as textiles and organic and inorganic additives which may be separated from the rubber portion of end-of-life tires prior to pyrolysis. Plastic pyrolysis oils obtained by pyrolysis of (predominantly) end-of-life tires are also known as tire pyrolysis oils (TPO). Examples of bio waste which can be comprised in "plastic waste” include green waste, food waste, human waste, manure, sewage, sewage sludge and slaughterhouse waste.

[0050] To obtain the plastic pyrolysis oil according to the present invention, the feedstock is inserted into a pyrolysis reactor using a dosing unit such as a screw or an extruder or a rotary valve or a pneumatic conveyor or a liquid injector. The feedstock is optionally pre-heated in e.g., a heat exchanger prior to insertion into the pyrolysis reactor and / or subjected to a pre-pyrolysis at a temperature in the range of, for example, from about 200 °C to about 360 °C. Next, the feedstock is heated in the pyrolysis reactor to a temperature in the range of from about 350 °C to about 900 °C, more preferably in the range of from 400 °C to about 550 °C, and a pressure in the range of from about 0.5 bar to about 2 bar (abs.), more preferably in the range of from 0.9 bar to about 1.5 bar (abs.). The pyrolysis reactor is preferably selected from the group comprising fluidized bed reactors, moving bed reactors, entrained flow reactors, screw reactors, extruders, stirred tank reactors and rotary kiln reactor. Preferably, the pyrolysis is performed in the pyrolysis reactor under an inert atmosphere exempt of oxygen or air.

[0051] Pyrolysis processes as such are known. They are described, e.g., in EP 0713906 A1 and WO 95 / 03375 A1. Suitable plastic pyrolysis oils are also commercially available. The plastic pyrolysis oil is typically a liquid at 15 °C or a wax at said temperature. "Liquid at 15 °C” in the terms of the present invention means that the plastic pyrolysis oil has a density of at most 1.3 g / ml, e.g., a density in the range from 0.65 to 0.98 g / ml, at 15 °C and 1013 mbar, as determined according to DIN EN ISO 12185.

[0052] The liquid stream S1 preferably comprises at least one plastic pyrolysis oil manufactured by the above-described methods. The liquid stream S1 further comprises organic compounds comprising at least one heteroatom and compounds having 0-0 double (olefins, dienes) and / or 0-0 triple bonds. "Further comprises” means here that such components are comprised in the at least one plastic pyrolysis oil and / or another liquid hydrocarbon which is mixed with the at least one plastic pyrolysis oil to form the liquid stream S1.

[0053] The at least one plastic pyrolysis oil comprised in the liquid stream S1 preferably has a bromine number of about 2 g Br2 / 100g to about 150 g E / IOOg (determined by ASTM 1159) and / or a C5 hydrocarbon content of about 0.03 wt.-% to about 12.2 wt.-% (determined by ASTM D 5134) and / or a naphthalene content of about 0.5 wt.-% to about 18.4 wt.-% (determined by ASTM D 5134) and / or a styrene content of about 0.02 wt.-% to about 29.5 wt.-% (determined by ASTM D 5134) and / or a toluene content of about 4.3 wt.-% to about 71.5 wt.-% (determined by ASTM D 5134). Such plastic pyrolysis oils or mixture of plastic pyrolysis oils in the liquid stream S1 are particularly suited for the method and the chemical plant according to the present invention.

[0054] Optionally, the at least one plastic pyrolysis oil is subjected to one or more methods selected from filtration, centrifugation, adsorption, washing, extraction before used as liquid stream S1 or portion thereof in the method according to the present invention and / or as liquid stream S1 or portion thereof for the chemical plant according to the present invention. Such optional pre-treatment methods are for example described in WO 2021 / 224287 A1, WO 2023 / 061834 A1, EP 0713906 A1, and WO 95 / 03375 A1 which are incorporated herein by reference. A skilled person knows how and in which cases to use pre-treatment methods disclosed in said documents and comparable pretreatment methods disclosed elsewhere.

[0055] A liquid stream S1 comprising at least one plastic pyrolysis oil, manufactured from the above-described feedstocks and the above-described methods or mixtures of such plastic pyrolysis oils is provided in step (I). The liquid stream S1 further comprises organic compounds comprising at least one heteroatom and compounds having C-C double and / or C-C triple bonds.

[0056] The liquid stream S1 may further comprise at least one further hydrocarbon liquid that is different from a plastic pyrolysis oil obtained by plastic pyrolysis oil of plastic waste. Suitable examples comprise bio-oils which are manufactured from biomass as source. Such optional further hydrocarbon liquids are explained in the following section:

[0057] Biomass is biological material derived from living, or recently living organisms. The biomass used for the manufacture of bio-oils may be any material of plant or animal origin that is in principle suitable to be converted at least into bio-oils. In particular, the term biomass comprises plants or parts thereof like crops, wood, or residues thereof, marine organisms like algae, and bio waste such as organic food waste, e.g., animal fat from meat industry waste, fish fat from fish processing waste, or used cooking oil. The bio-oils can also be manufactured from more than one of the above-mentioned sources. The biomass is of plant or animal origin or a mixture thereof, preferably it is of plant origin.

[0058] Preferably, said biomass of plant origin comprises or is derived from algae, oil crops, oil palms, soybeans, rapeseed, mustard, flax, cottonseed, sunflower, corn, hemp, field pennycress, pongamia, jatropha, mahua, camelina, salicornia, carinata, lignocellulose, wood, forestry residues, agricultural residues, crop residues, residues from vegetable oil production, green waste, food waste, and used vegetable cooking oil, more preferably it comprises or is derived from algae, oil crops, oil palms, soybeans, rapeseed, pongamia, jatropha, camelina, and carinata.

[0059] In case the biomass is of animal origin, it preferably comprises or is derived from animal fat, livestock-related products like tallow, fish fat, or food waste.

[0060] The biomass is converted to a liquid hydrocarbon feedstock which is different from plastic pyrolysis oils obtained by pyrolysis of plastic waste and can be comprised in the liquid stream S1. Such conversion may comprise both mechanical and physical operations, like harvesting and collecting as well as crushing, cracking, cutting, shredding, grinding, chipping, milling, extrusion, irradiation, squeezing, pressing, filtering, sieving, adsorption, and thermal treatments such as drying and torrefaction, and chemical processes, like extraction, distillation, thermochemical conversions like pyrolysis or hydrothermal liquefaction, hydrolysis, saponification, neutralization, or ketonization. Also, the mechanical, physical, and / or chemical separation of the products and by-products of said operations and processes, in particular the separation of gaseous, liquid, and solid fractions, forms part of the biomass processing. In essence, said processing comprises the removal of all by-products from the biomass conversion product stream that are not suitable or are detrimental for further use in the stream S1. The right choice of suitable process steps and operating conditions is mainly dependent on the biomass to be processed; but the one skilled in the art will be familiar with such considerations.

[0061] The product stream obtained by said biomass processing comprises, preferably consists of bio-oil. Bio-oil designates a liquid compound mixture mainly comprising highly oxygenated compounds (e.g., glycerides, esters, carboxylic acids, phenols, alcohols, ketones, aldehydes, furans, and sugars) and water, while its exact composition depends on the biomass feedstocks and the processing steps applied. The term bio-oil includes in particular vegetable oils like rapeseed oil, sunflower oil, soybean oil, corn oil, and palm oil, waste cooking oil, tall oil, animal fats, and oils obtained by thermochemical conversion of biomass, e.g., biomass-derived pyrolysis or hydrothermal liquefaction oils.

[0062] Thus, according to one embodiment of the present invention, the processing of biomass in the manufacture of the feedstock provided in step (I) comprises mechanical and physical operations and chemical processes, optionally also the separation of the obtained products and any by-products.

[0063] According to another embodiment of the present invention, the processing of biomass in the manufacture of the feedstock for use in the stream S1 comprises extraction, pyrolysis, and / or hydrothermal liquefaction of the biomass.

[0064] Such further liquid hydrocarbon feedstock (in case more than one liquid hydrocarbon feedstocks the sum of all liquid hydrocarbon feedstocks) can be comprised in the liquid stream S1 for example in a quantity of 0 wt.-%, 5 wt.-%, 10 wt.-%, 15 wt.-%, 20 wt.-%, 25 wt.-%, 30 wt.-%, 35 wt.-%, 40 wt.-%, 45 wt.-%, 50 wt.-%, 55 wt.-%, 60 wt.-%, 65 wt.-%, 70 wt.-%, 75 wt.-%, 80 wt.-% or more with the proviso that at least 2 wt.-% of the liquid stream S1 are comprised of at least one plastic pyrolysis oil manufactured by pyrolysis of plastic waste.

[0065] A stream S2 comprising H2 is provided in step (II) of the method according to the present invention. The stream S2 can consist essentially of H2 or comprise H2 together with at least one other gas. Preferably the H2 content of the stream S2 is higher than about 50 Vol.-%, more preferably higher than 80 Vol.-% and most preferably higher than about 99 Vol.-%. This minimizes the amount of purge-gas needed to keep the H2 partial pressure high and saves H2. Furthermore, a high H2 partial pressure promotes the catalyst activity and allows low reaction temperatures.

[0066] The advantage of low reaction temperatures is that undesired polymerization of components in stream S3 is suppressed. Furthermore, the stream S2 and stream S11 dilutes reactive components such as compounds having C-C double bonds (e.g., dienes), compounds comprising C-C triple bonds and styrene comprised in the in the liquid stream S1 which further minimizes undesired polymerization of said reactive components in devices and units used in the method according to the present invention, particularly in the evaporation unit EU and / or in the optional superheater SH and / or in the first hydroprocessing unit HU1. In addition to minimizing said undesired polymerization, the dilution also reduces the partial pressure of said reactive components in stream S1 and thereby lowers the dew point of said reactive components in stream S1 . Hence, desired high evaporation rates of the components in stream S1 at a reduced temperature in the evaporation unit EU are achieved compared to undiluted reactive components in stream S1. The dilution during evaporation further suppresses the undesired polymerization of said reactive components in stream S1 .

[0067] Hydrogen (H2) used in the method and system according to the present invention is preferably "green hydrogen” which is generated for example by electrolysis of water using electricity at least partially generated from renewable energy sources (e.g., solar energy, wind energy, tidal energy, and nuclear energy) and / or low-carbon energy sources and / or a methane pyrolysis, preferably a methane pyrolysis using at least partially methane from a renewable source. Methane from a renewable source comprises biomethane.

[0068] Optionally at least a portion of the hydrogen used in the method according to the present invention is hydrogen formed during the pyrolysis reaction and separated from the volatile pyrolysis reaction products.

[0069] Next, in step (ill) of the method according to the present invention, the liquid stream S1 and the stream S2 are fed, together with a recycle gas stream S11 into an evaporation unit EU in which at least a portion of the liquid stream S1 is evaporated and leaving the evaporation unit EU, mixed with stream S2 and together with a recycle gas stream S11 , as gaseous stream S3. Those portions of the liquid stream S1 not evaporated in the evaporation unit EU leave the evaporation unit EU as liquid stream S4.

[0070] Preferably, the liquid stream S1 provided in step (I) and the stream S2 provided in step (ii) are mixed before entering the evaporation unit EU and / or mixed inside the evaporation unit EU.

[0071] Preferably, the evaporation of the liquid stream S1 is a mild evaporation, for example not in one stage but in more than one evaporation stages. The desired mild evaporation of the liquid stream S1 is also achieved by adding a recycle gas stream S11 to the liquid stream S1 prior and / or during evaporation.

[0072] The desired mild evaporation of the liquid stream S1 is more preferably achieved by evaporating the liquid stream S1 in more than one evaporation stages and adding a recycle gas stream S11 to the liquid stream S1 prior and / or during evaporation.

[0073] The advantage of such a mild evaporation of the liquid stream S1 is a reduced polymerization of components present in the liquid stream S1 such as olefins, dienes and other polymerizable organic compounds such as styrene and organic compounds comprising C-C triple bonds. In case the evaporation conditions are too harsh, undesired fouling in units, tubes and other equipment used for the method according to the present invention occurs. Such undesired fouling is caused by the above-described polymerization.

[0074] The evaporation unit EU comprises at least one evaporator selected from the group comprising pre-evaporators, stage evaporators, and combinations thereof. Such evaporators can be rotary evaporators, circulation evaporators, falling film evaporators, rising film evaporators, climbing film plate evaporators, falling film plate evaporators, multipleeffect evaporators, agitated falling film evaporators, and micro-structured evaporators.

[0075] In one aspect of the present invention, the evaporation unit EU comprises at least one stage evaporator. Preferably, the evaporation unit EU comprising at least one stage evaporator and further comprises at least one pre-evaporator which is upstream of and fluidically connected to the at least one stage evaporator.

[0076] In another aspect the evaporation unit EU comprises at least one pre-evaporator or for example a series of preevaporators in which the liquid stream S1 is heated stepwise and thereby undesired polymerization of compounds having C-C double bonds (e.g., dienes, olefins), compounds comprising C-C triple bonds and styrene comprised in the in the liquid stream S1 is reduced.

[0077] In another aspect of the present invention, the evaporation unit EU comprises at least one falling film evaporator which is particularly suited for the desired mild evaporation of the liquid stream S1.

[0078] Multistage evaporation and suitable devices are for example described in R. Billet, Ullmann's Encyclopedia of Industrial Chemistry, 2012, Vol. 13, Chapter "Evaporation”, pages 588 to 591 and 597 to 599 which is incorporated herein by reference.

[0079] The temperature for evaporating at least a portion of the liquid stream S1 preferably ranges from about 140 °C to about 220°C, more preferably from about 160°C to about 200 °C and most preferably from about 170 °C to about 190 °C.

[0080] At least one evaporator comprised in the evaporation unit EU optionally further comprises at least a second fluidic passage through which another stream than stream S1 , stream S2, stream S3, stream S4 and recycle gas stream S11 can flow and thereby transfer heat to the liquid stream S1 and the stream S2 and the recycle gas stream S11 which flow to first fluidic passage comprised said at least one evaporator. The first fluidic passage and the at least one second fluidic passage have no fluidic connection between each other. Preferably, the sole reason for the optional presence of at least a second fluidic passage in at least one evaporator of the evaporation unit EU is the heat transfer from a stream which flows to said at least one second fluidic passage to the stream(s) flowing through the first fluidic passage. Heat may be transferred from the stream S8c to the liquid stream S1 and / or an already partially vaporized stream S1 and / or stream S2 and to the recycle gas stream S11 . Stream S8c will be explained in detail further below.

[0081] Accordingly, at least a portion of the thermal energy required for the evaporation of the liquid stream S1 in step (iii) of the method according to the present invention is optionally provided by heat transfer from the stream S8c to the liquid stream S1 and / or an already partially vaporized stream S1 and / or stream S2 and to the recycle gas stream S11 . This embodiment is shown in figure 3. Next, in optional step (iv) of the method according to the present invention the gaseous stream S3 is superheated in at least one optional superheater SH and thereby a superheated and / or dry stream S5 is formed. The advantage of applying optional step (iv) in the method according to the present invention is as follows: in case the gaseous stream S3 having a temperature lower than the dew point, vapor and liquid phase enters directly the first hydroprocessing unit HU1 which is not desired. Small amounts of liquid can be separated at the bottom of the at least one reactor in the first hydroprocessing unit HU1 if necessary. The first hydroprocessing unit HU1 is optimized for gas phase hydrogenation, hence the gaseous stream S3 is preferably completely vaporized before entering the first hydroprocessing unit HU1 to avoid polymerization and therefore plugging. Due to heat loss on the way from the evaporation unit EU to the first hydroprocessing unit HU1 a liquid phase may be formed by condensation which should preferably not enter the first hydroprocessing unit HU1 because of the reasons explained above.

[0082] Therefore, the gaseous stream S3 is optionally and preferably superheated in at least one optional superheater SH to raise the temperature of the gaseous stream S3 preferably by about 2 °C to about 50 °C, more preferably by about 5 °C to about 40 °C and most preferably by about 10 °C to about 30 °C in respect to the temperature at which the gaseous stream S3 leaves the evaporation unit EU.

[0083] The at least one optional superheater SH more preferably comprises at least one first fluidic passage into which the gaseous stream S3 is fed, superheated, and is leaving the optional superheater SH as superheated stream S5. The superheated stream S5 has a higher temperature than the gaseous stream S3.

[0084] The at least one optional superheater SH is preferably a radiant superheater, a convection superheater, or a separately fired superheater. Preferably, the at least one optional superheater SH is a shell and tube heat exchanger with gaseous stream S3 inside the tubes. In one aspect of the present invention, at least a portion of the thermal energy transferred to the gaseous stream S3 in the at least one optional superheater SH is provided by electrical heating, preferably with electricity from a renewable source such as wind energy, solar energy and / or tidal energy.

[0085] Preferably, the optional superheater SH further comprises at least one heat exchanger such as a shell and tube heat exchanger which comprises at least a first fluidic passage into which the gaseous stream S3 is fed (preferably the tubes), superheated and is leaving the optional superheater SH as superheated stream S5 and at least one second fluidic passage (preferably the shell) through which another stream than the gaseous stream S3 can flow and thereby transfer heat to the gaseous stream S3 which flows through the first fluidic passage. This embodiment is shown in Figure 3.

[0086] The first fluidic passage and the optional at least one second fluidic passage have no fluidic connection between each other. Preferably, heat is transferred from the stream S8 to the gaseous stream S3. Stream S8 will be explained in detail further below. More preferably, at least a portion of the thermal energy required for conversion of the gaseous stream S3 into the superheated stream S5 in the at least one optional superheater SH is provided by transferring heat form the stream S8 to the gaseous stream S3.

[0087] Most preferably, up to 100 % of the thermal energy required for conversion of the gaseous stream S3 into the superheated stream S5 in the at least one optional superheater SH is provided by transferring heat form the stream S8 to the gaseous stream S3.

[0088] Stream S8 leaves the at least one optional super heater SH as stream S8b in the aspect of the present invention also shown in Figure 4.

[0089] In method step (v) of the method according to the invention, the gaseous stream S3 (Figure 2) or the superheated stream S5 (in case optional step (iv) is applied, Figure 3) is fed into a first hydroprocessing unit HU1 in which compounds comprising C-C double bonds (e.g., dienes) and / or C-C triple bonds present in the gaseous stream S3 or the superheated stream S5 are hydrogenated in a first hydroprocessing unit HU1. Thereby, C-C single bonds are formed.

[0090] The first hydroprocessing unit HU1 comprising at least one stage, in which C-C double and / or C-C triple bonds present in the gaseous stream S3 or the superheated stream S5 are hydrogenated.

[0091] The first hydroprocessing unit HU1 may be any vessel preferably configured to contain a hydroprocessing catalyst. The vessel is preferably configured for gas phase operation. The first hydroprocessing unit HU1 may include one or more beds of the hydroprocessing catalyst, preferably in fixed bed configuration. The first hydroprocessing unit HU1 can be operated adiabatically, isothermally, non-adiabatically, non-isothermally, or combinations thereof. The first hydroprocessing unit HU1 may comprises more than one vessel. Each of such vessels is considered a hydrogenation reactor ("reactor”).

[0092] The gaseous stream S3 or the superheated stream S5 can be contacted with the hydroprocessing catalyst in upward flow, downward flow, radial flow, or combinations thereof.

[0093] Preferably, the first hydroprocessing unit HU1 comprises one single reactor having one single catalyst bed. Thereby, the geometric shape of the first hydroprocessing unit HU1 is minimized, and a cost-efficient reactor design is assured.

[0094] The process temperature depends on catalyst type used and the degree of activity of the catalyst. The process temperature in the first hydroprocessing unit HU1 preferably ranges from about 140 °C to about 250 °C, more preferably from about 150 °C to about 200 °C and most preferably from about 170 °C to about 190 °C. The deactivation of the catalyst can optionally be compensated by raising the process temperature. The pressure in the first hydroprocessing unit HU1 preferably ranges from about 1.0 MPa to about 10 MPa abs. in the process. The hydrogen partial pressure in front of the first hydroprocessing unit HU1 preferably ranges from about 5 bar to about 50 bar, more preferably from about 10 bar to about 30 bar and most preferably from about 14 bar to about 20 bar.

[0095] The weight hourly space velocity (WHSV) calculated with reference to the stream S1 preferably ranges from about 0.5 t / (m3Kat 'h) to about 5 t / (m3Kat h), more preferably from about 1.0 t / (m3Kat / h) to about 3.0 t / (m3Kat / h) and most preferably from about 1.5 t / (m3Kat / h) to about 2.0 t / (m3Kat / h).

[0096] The amount of hydrogen exhibits a large excess comprised in the first hydroprocessing unit HU1. The process conditions for hydrogen partial pressure, temperature and WHSV as disclosed above ensure a sufficient hydrogenation of the undesired C-C double bonds (e.g. , olefins, dienes) and C-C triple bonds present in the gaseous stream S3 or optionally the superheated stream S5.

[0097] The hydroprocessing catalyst may be any catalyst used for hydrogenation of C-C double bonds (e.g., olefins, dienes), and C-C triple bonds (e.g., commercially available hydroprocessing catalysts). Suitable hydroprocessing catalysts for this purpose are heterogeneous catalyst selected from the group comprising or consisting of molybdenum catalysts ("Mo catalysts”), cobalt-molybdenum catalysts ("Co-Mo catalysts”), nickel-molybdenum catalysts ("Ni-Mo catalysts”), tungsten-molybdenum catalysts (“W-Mo catalysts”), cobalt-molybdenum oxides, nickelmolybdenum oxides, tungsten-molybdenum oxides, cobalt-molybdenum sulfides, nickel-molybdenum sulfides, tungsten-molybdenum sulfides, molybdenum sulfides. Suitable heterogeneous catalysts further comprise a support, preferably an inorganic support selected from the group comprising or consisting of silica, alumina, silica-aluminas, magnesia, clays, and mixtures thereof. Further suitable hydroprocessing catalysts are for example zeolites comprising one or more metals.

[0098] Most preferably, the at least one heterogeneous catalyst is selected from the group consisting of nickel-molybdenum catalysts and nickel-tungsten catalysts further comprising a support, preferably an inorganic support selected from the group comprising or consisting of silica, alumina, silica-aluminas, magnesia, clays, and mixtures thereof. These catalysts are the most suited ones for the desired hydrotreatment reactions in the first hydroprocessing unit HU1 (step (v) of the method according to the present invention).

[0099] More than one of the aforementioned hydroprocessing catalysts can be used together in the first hydroprocessing unit HU1.

[0100] In one aspect of the present invention, at least a portion of the catalyst comprises recycled catalysts. In the context of the present invention, the at least one catalyst for the first hydroprocessing unit HU1 preferably is in the form of extrudates, pellets, rings, spherical particles or spheres, more preferably spherical particles or extrudates.

[0101] The at least one reactor in the first hydroprocessing unit HU1 comprises the at least one catalyst preferably in form of at least one catalyst bed.

[0102] The height and diameter of the at least one catalyst bed is chosen on reaction kinetics and optimal I iquid / gas flowpattern and pressure drop. The at least one catalyst bed may consist of one or more layers of different solid absorption materials, and one or more different hydrogenation catalysts. The catalyst layers in the at least one catalyst bed may differ from each other by particle size or shape or activity or active sites of material. Inert particles may be used above and below each bed to improve fluid distribution in case more than one catalyst bed is used.

[0103] In case the at least one hydrogenation reactor in the first hydroprocessing unit HU 1 has at least two stages, the catalyst preferably has different particle size in at least two stages and / or optionally different shape in the at least two stages.

[0104] The particle size means here particle size distribution, which is measured for example by sieve methods, laser diffraction methods or other methods known in the art. A catalyst having a desired particle size and optionally desired shape may be manufactured and used.

[0105] The hydrogenation reaction is an exothermic reaction and therefore each reaction stage may optionally be cooled.

[0106] Preferably, the gaseous stream S3 or the superheated stream S5 enters the at least one reactor of the first hydroprocessing unit HU1 from the bottom section and leaves the at least one reactor of the first hydroprocessing unit HU1 in the top section. Thereby, undesired fouling such as polymerization of reactive compounds (e.g., organic compounds having C-C double and / or triple bonds) is reduced and / or undesired polymerization products formed in the bottom section of the at least one reactor are drawn further down and away from the bottom section of the catalyst bed by gravity. Such undesired polymerization products can then be removed from the bottom section of the reactor without blocking further sections of the at least one catalyst bed in the at least one reactor.

[0107] About 80 % or more, such as 85 % or 95 % of the dienes present in the gaseous stream S3 or the superheated stream S5 are converted in step (v) of the method according to the present invention.

[0108] Next, in step (vi) of the method according to the present invention, the temperature of the gaseous stream S6 is increased in a heating device HD to form a heated gaseous stream S7. The temperature increasement is required because the hydrotreatment in the second hydroprocessing unit HU2 requires a higher temperature of the gaseous stream to be hydrotreated than the first hydrotreatment in the first hydroprocessing unit HU1. The gaseous stream S6 preferably has a temperature in the range of about 160 °C to about 280 °C, more preferably of about 180 °C to about 230 °C and most preferably of about 180 °C to about 200 °C.

[0109] The heated gaseous stream S7 preferably has a temperature in the range of about 200 °C to about 400 °C, more preferably of about 260 °C to about 380 °C and most preferably of about 280 °C to about 340 °C.

[0110] The at least one heating device HD provides heat to the gaseous stream S6 by direct heating, indirect heating, or a combination thereof (e.g., direct heating with a first heating device HDa and indirect heating with a second heating device HDb or vice versa).

[0111] The at least one heating device HD is preferably selected from the group comprising direct fired heaters, furnaces powered by electrical energy, and heat exchangers.

[0112] In case the at least one heating device HD comprises a furnace powered by electrical energy, the electricity is preferably provided by a renewable source such as wind energy, solar energy, and tidal energy. Such heating devices HD are more sustainable than e.g., direct fired furnaces and are therefore preferred.

[0113] Direct fired furnaces as heating device HD can be for example provide heat to the gaseous stream by combustion of a gaseous or liquid fuel such as natural gas and an oxidant such as oxygen and / or air.

[0114] Furnaces suitable as heating devices HD may comprise for example at least one radiant section, at least one convection section, at least one radiant coil, at least one burner and an insulation.

[0115] The heating device HD is downstream of and fluidically connected to the at least one outlet of the first hydroprocessing unit HD1.

[0116] Next, in step (vii) of the method according to the present invention, the heated gaseous stream S7 is inserted into a second hydroprocessing unit HU2 and converted in the second hydroprocessing unit HU2 to a product stream S8. The product stream S8 is depleted in heteroatoms such as nitrogen, oxygen, halogens (fluorine, chlorine, bromine, iodine), and sulfur in respect to the heated gaseous stream S7 by a hydrotreatment in the second hydroprocessing unit HU2. A hydrogenation of aromatic rings may also occur in the second hydroprocessing unit HU2.

[0117] The heteroatoms leave the second hydroprocessing unit HU2 in form of their respective hydrogenated species as part of the product stream S8. The respective hydrogenated species of heteroatoms comprise NH3, H2O, H(Hal) (HF, HCI, HBr, HI), and H2S. NH3and H(Hal) may form salts of type NH4Hal (NH4F, NH4CI, NH4Br, NH4I) and NH3and H2S may form the salt NH4SH. Such salts may be formed already in the gas phase in the second hydroprocessing unit HU2 and can then form undesired deposits on metal surfaces by resublimation when stream S8 is cooled down. NH4CI, NH4F, NH4Br, NH4I and NH4SH of which at least one may be formed mainly in the second hydroprocessing unit HU2 (a minor portion may also be formed in the first hydroprocessing unit HU1) are preferably removed from the second hydroprocessing unit HU2 by water. More preferably, NH4F, NH4CI, NH4Br, NH4I and / or the respective cations and anions are removed quantitatively with water and NH4SH and / or the respective cation and anion is / are partly removed from the second hydroprocessing unit HU2 with a water stream S15.

[0118] A water stream S15 is fed to the product stream S8. Thereby, a product stream comprising water S8a is formed (aspect of the present invention shown in figure 2) or a water stream S15 is fed to a product stream S8b and thereby a product stream S8c is formed (aspect of the present invention shown in figure 3). The addition of a water stream S15 to a product stream S8 or a product stream S8b is further explained below.

[0119] Accordingly, the reactions in the second hydroprocessing unit comprise hydrodenitrogenation, hydrodeoxygenation, hydrodehalogenation and hydrodesulfurization. Furthermore, the reactions comprise hydrodemetallization and, preferably, also hydrogenation of the remaining C-C double bonds (olefins and dienes) and C-C triple bonds.

[0120] The second hydroprocessing unit HU2 is downstream of and the at least one inlet of the second hydroprocessing unit HU2 is fluidically connected to the heating device HD.

[0121] The second hydroprocessing unit HU2 may be any vessel configured to contain the at least one hydroprocessing catalyst disclosed herein. The vessel is preferably configured for gas phase operation. The second hydroprocessing unit HU2 may include one or more beds of the hydroprocessing catalyst, preferably in fixed bed configuration. The second hydroprocessing unit HU2 can be operated adiabatically, isothermally, non-adiabatically, non-isothermally, or combinations thereof. The second hydroprocessing unit HU2 may comprises more than one vessel. Each of such vessels is considered a hydrogenation reactor.

[0122] The heated gaseous stream S7 can be contacted with the at least one hydroprocessing catalyst in upward flow, downward flow, radial flow, or combinations thereof. Preferably, the heated gaseous stream S7 is contacted with the at least one hydroprocessing catalyst in downward flow.

[0123] Preferably, the heated gaseous stream S7 enters the at least one hydrogenation reactor in the second hydroprocessing unit HU2 from the top section.

[0124] The at least one hydroprocessing catalyst may be any catalyst used for hydrogenation of C-C double bonds (e.g., olefins, dienes) and heteroatom hydrogenation (e.g., commercially available hydroprocessing catalysts). Suitable hydroprocessing catalysts for this purpose are selected from the group comprising or consisting of molybdenum catalysts ("Mo catalysts”), cobalt-molybdenum catalysts ("Co-Mo catalysts”), nickel-molybdenum catalysts ("Ni-Mo catalysts”), tungsten-molybdenum catalysts ("W-Mo catalysts”), cobalt-molybdenum oxides, nickel-molybdenum oxides, tungsten-molybdenum oxides, cobalt-molybdenum sulfides, nickel-molybdenum sulfides, tungsten- molybdenum sulfides, molybdenum sulfides. Suitable catalysts further comprise a support, preferably an inorganic support selected from the group comprising or consisting of silica, alumina, silica-aluminas, magnesia, clays, and mixtures thereof. Further suitable hydroprocessing catalysts are for example zeolites comprising one or more metals.

[0125] More preferably, the at least one hydroprocessing catalyst is selected from the group consisting of molybdenum catalysts, nickel-molybdenum catalysts, and nickel-tungsten catalysts. These catalysts are the most suited ones for the desired hydrotreatment reactions in the second hydroprocessing unit HU2 (step (vii) of the method according to the present invention). Most preferably, a nickel-molybdenum catalyst is used in the at least one hydrogenation reactor in the second hydroprocessing unit HU2, preferably in case the heated gaseous stream S7 enters the at least one hydrogenation reactor in the second hydroprocessing unit HU2 from the top section.

[0126] More than one of the aforementioned hydroprocessing catalysts can be used together in the second hydroprocessing unit HU2, for example mixed together or as separate catalyst stacks in which each of said stacks comprises one type of catalyst, e.g., in an order stack a (with catalyst A) I stack b (with catalyst B).

[0127] In one aspect of the present invention, at least a portion of the catalyst comprises recycled catalysts.

[0128] The height and diameter of the at least one catalyst bed is chosen on reaction kinetics and optimal gas flow-pattern and pressure drop. The at least one catalyst bed may consist of one or more layers of different solid absorption materials, and one or more layers of the same or different hydrogenation catalysts. The catalyst layers in the at least one catalyst bed may differ from each other by particle size or shape or activity or active sites of material. Inert particles may be used above and below each bed to improve fluid distribution in case more than one catalyst bed is used.

[0129] In the context of the present invention, the at least one hydroprocessing catalyst for the second hydroprocessing unit HU2 preferably is in the form of extrudates, pellets, rings, spherical particles or spheres, more preferably in the form of spherical particles or extrudates.

[0130] In case the at least one hydrogenation reactor (vessel) in the second hydroprocessing unit HU2 has at least two stages, the at least one hydroprocessing catalyst preferably has different particle size in at least two stages and / or optionally different shape in the at least two stages.

[0131] The particle size means here particle size distribution, which is measured for example by sieve methods, laser diffraction methods or other methods known in the art. A catalyst having a desired particle size and optionally desired shape may be manufactured and used.

[0132] The hydrogenation reaction is an exothermic reaction and therefore each reaction stage may optionally be cooled. An external cooling medium and / or mixing of stream S7 with at least a portion of the cold recycle gas (stream S6") can be utilized for said cooling. The second hydroprocessing unit HU2 can be operated at various process conditions. For example, the heated gaseous stream S7 is contacted with the at least one hydroprocessing catalyst at a temperature of preferably from about 200 °C to about 400 °C, more preferably from about 250 °C to about 380 °C and most preferably from about 280 °C to about 360 °C.

[0133] The temperature in the second hydroprocessing unit HU2 is attained by using a heated gaseous stream S7 which was further heated using the heating unit HU which is upstream and fluidically connected to the second hydroprocessing unit HU2.

[0134] The pressure in the second hydroprocessing unit HU2 preferably ranges from about 1.0 to about 10 MPa abs. in the process. The hydrogen partial pressure in front of the second hydroprocessing unit HU2 ranges from about 5 bar to about 50 bar more preferably from about 10 bar to about 30 bar and most preferably from about 14 bar to about 20 bar.

[0135] The weight hourly space velocity (WHSV) referring the stream S1 and the catalyst in the hydroprocessing unit HU2 preferably ranges from about 0.1 t / (m3Kat / h) to about 5.0 t / (m3Kat h), more preferably from about 0.5 t / (m3Kat / h) to about 1.0 t / (m3Kat / h).

[0136] The organic compounds comprising at least one heteroatom in stream S3 are depleted in the second hydroprocessing unit HU2 in respect to stream S1 , preferably the organic compounds comprising sulfur in stream S8 are depleted by at least 90 % in respect to stream S1 and / or the organic compounds in stream S8 comprising halogens are depleted by at least 97 % in respect to stream S1 and / or the organic compounds in stream S8 comprising nitrogen are depleted by at least 99 % in respect to stream S1.

[0137] More preferably, the product stream S8, or a portion thereof is not recycled (inserted again) into the first hydroprocessing unit HU1 and / or into the second hydroprocessing unit HU2.

[0138] There is no need to recycle a portion of the product stream S8 or a portion thereof into the first hydroprocessing unit HU1 because the gaseous stream S6 is stable enough in respect to undesired polymerization and therefore, the gaseous stream S6 can be further heated up in the heating device HD for insertion into the second hydroprocessing unit HU2. Preferably, stream S8 or a portion thereof is not recycled into the first hydroprocessing unit HU1. This enables to build the first hydroprocessing unit HU1 (liquid recycle stream S3' included) and the second hydroprocessing unit HU2 (recycle-gas included) for "once through capacity” which means that the stream S1 (and the streams obtained thereof by conversion in the individual process units) only flow(s) once through the first hydroprocessing unit HU1 (which it leaves as stream S6) and the second hydroprocessing unit HU2 and then leaves the second hydroprocessing unit HU2, converted, as stream S6. The method according to the present invention further comprising the optional step (iv) is shown in Figure 3.

[0139] Next, in optional step (viii) of the method according to the present invention, the product stream S8 flows to a section of the at least one optional superheater (SH) which is suited for transferring heat from the product stream S8 to the gaseous stream S3 which flows in a fluidically separated sections of the at least one optional superheater (SH) which is suited for transferring heat from the product stream S8 to the gaseous stream S3.

[0140] Thereby, the product stream S8 is converted to the cooled down product stream S8b and the gaseous stream S3 is converted into the superheated gaseous stream S5.

[0141] The method according to the present invention further comprising the optional steps (iv), (viii) and (x) is shown in Figure 4.

[0142] A washing water stream S15 is preferably feed to the product stream S8 or the product stream S8b. Thereby, NH4CI, NH4F, NH4Br, NH4I and NH4SH of which at least one may be formed in the second hydroprocessing unit HU2 is / are transferred from the product stream S8 into stream S8a (Figures 2 and 3) or stream S8b (Figure 4). Said streams S8a or S8b comprise at least one of NH4CI, NH4F, NH4Br, NH4I and NH4SH and / or the corresponding cations and anions. The portions of streams S8a or S8b comprising at least one of NH4CI, NH4F, N H4Br, NH4I and NH4SH and / or the corresponding cations and anions are later separated from the liquid product stream S9 in the separation unit SU as waste water stream S17 (Figures 2 to 4).

[0143] The water stream S15 can be added to the product stream S8 or the product stream S8b continuously or discontinuously. In case the water stream S15 is added to the product stream S8 or the product stream S8b discontinuously, stream S15 is for example added in case the characteristics of the heat transfer inside the condensation unit CU and / or the separation unit SU change, which change is indicating the formation of undesired deposits of at least one of NH4CI, NH4F, NH4Br, NH4I and NH4SH inside the second hydroprocessing unit HU2 and / or the condensation unit CU and / or the separation unit SU, and / or said undesired deposits are recognized by another means such as based on a fixed maintenance schedule which is derived on experience by ongoing use of the chemical plant. Furthermore, undesired corrosion on and / or of metal surfaces is reduced when the deposition of the above-described salt thereon is avoided.

[0144] Next, in optional step (ix) a washing water stream S15 is fed to the cooled down product stream S8b and thereby a product stream comprising washing water S8c is formed (Figure 4). The washing water of the washing water stream S15 is required to remove the above-mentioned salts which can be formed as side-product(s) in the second hydroprocessing unit HU2. Such salts and / or the corresponding cations and anions can then be comprised in the product stream S8 and product stream S8a or in product stream S8 and the successively cooled down product streams S8b, S8c and S8d from said product streams and can be separated in the at least one separation unit SU (step (xii) of the method according to the present invention) from the liquid product stream S9 as a waste water stream S17 in which said salt(s) are comprised.

[0145] Next, in optional step (x) of the method according to the present invention, the cooled down product stream comprising washing water S8c flows to a section of the evaporation unit EU which is suited for transferring heat from the cooled down product stream comprising washing water S8c to the liquid stream S1 (comprising gaseous stream S2 and at least a portion of the optional recycle gas stream S11) which flows to a fluidically separated section of the evaporation unit EU. Thereby, stream S3 is formed (= the evaporated liquid stream S1 comprising the gaseous stream S2 and at least a portion of the optional recycle stream S11). This optional method step is shown in Figure 4.

[0146] Thereby, the cooled down product stream comprising washing water S8c is converted to the further cooled down product stream S8d and the liquid stream S1 comprising gaseous stream S2 and at least a portion of the optional recycle gas stream S11 is converted into the gaseous stream S3.

[0147] Optional step (viii) and optional step (x) can be applied in the method according to the present invention or can be both omitted or either step (viii) or step (x) can be applied.

[0148] Next, in step (xi) of the method according to the present invention, the product stream S8 or optionally, one of the streams selected from the group consisting of the cooled down product stream S8b, the cooled down product stream comprising washing water S8c, and the further cooled down product stream S8d, is condensed in at least one condensation unit CU to a liquid product stream S9. This step is required to enable the separation of a recycle gas stream S11 which comprises hydrogen not converted in the first hydroprocessing unit HU1 and / or the second hydroprocessing unit HU2.

[0149] The condensation unit CU can be for example a device in which the product stream S8 or optionally, one of the streams selected from the group consisting of the cooled down product stream S8b, the cooled down product stream comprising washing water S8c, and the further cooled down product stream S8d is cooled down by directly and / or indirectly contacting said product stream S8 or optionally, one of the streams selected from the group consisting of the cooled down product stream S8b, the cooled down product stream comprising washing water S8c, and the further cooled down product stream S8d with another stream which has a lower temperature than said product stream S8 or optionally, one of the streams selected from the group consisting of the cooled down product stream S8b, the cooled down product stream comprising washing water S8c, and the further cooled down product stream S8d before both streams are brought in contact. Suitable condensation units CU comprise, heat exchangers, with cooling media such as air, cooling water, and other media having a suitable low temperature.

[0150] Most preferably, the at least one condensation unit CU is selected from the group comprising air-cooler and watercooler. The at least one condensation unit CU is downstream of and fluidically connected to the at least one outlet of the second hydroprocessing unit HU2 (Figures 2 and 3) or to the at least one evaporation unit EU (Figure 4).

[0151] Next, in step (xii) of the method according to the present invention, the product stream S9 is separated into a refined product stream S10 which comprises the valued components having the desired boiling point range for the later application as a steam cracker feedstock, a recycle gas stream S11 which comprises hydrogen not converted in the first hydroprocessing unit HU1 and the second hydroprocessing unit HU2, and a waste water stream S17.

[0152] The recycle gas stream S11 is then inserted into the evaporation unit EU and the hydrogen comprised therein is utilized as for hydrogenation reactions in the first hydroprogessing unit HU1 and the second hydroprocessing unit HU2 together with hydrogen comprised in the gaseous stream S2.

[0153] It's beneficial to feed the recycle gas stream S11 back to the evaporation unit EU to save large amounts of hydrogen. Such a use of a recycle-gas stream S11 as described above is also beneficial to evaporate the components of feed stream S1 .

[0154] The "recycle-gas stream S11 to stream S1” ratio is preferably between about 300 Nm3 / t to about 2000 Nm3 / t, more preferably between 600 Nm3 / t to about 1400 Nm3 / t.

[0155] To maintain a high H2 partial pressure in the first hydroprocessing unit HU1 and the second hydroprocessing unit HU2, a purge-gas stream from the recycle gas stream S11 may be used, preferably, when the H2 concentration in stream S2 is lower than 99.9 Vol.-%, to avoid accumulation of inert gaseous components such as N2, CH4, and C2H6 in the recycle gas stream S11 . The purge-gas stream is a portion of the recycle gas stream S11 which is optionally removed from the recycle gas stream S11 to prevent an undesired accumulation (concentration increase) of said inert gaseous components.

[0156] The waste water stream S17 comprises at least one salt selected from the group comprising NH4F, NH4CI, NH4Br, NH4I, and NH4SH which can be formed in the second hydroprocessing unit HU2 as side-product(s).

[0157] The waste water stream S17 is the preferably subjected to a waste water treatment, for example a separation of the dissolved H2S and NH3 in a sour water stripper unit and transferring the waste water then to waste water treatment plant.

[0158] The separation unit SU is downstream of and fluidically connected to the at least one condensation unit CU.

[0159] The separation unit SU can be for example a liquid-liquid-vapor separation unit, preferably using one or more of hydrocyclone, settler tank, centrifuge, more preferably using one or more of settler tank and / or centrifuge. Next, in step (xiii) of the method according to the present invention the refined product stream S10 is subjected to a distillation in a distillation unit DU for separating the refined product stream S10 into a stabilized product stream S12.

[0160] In the distillation unit DU, the dissolved gases (H2, CH4, C2H6, C3H8, H2S and NH3) are separated as stream S13 from the valued product fraction (stream S12). Thereby, the dissolved gases are removed to obtain a stable feed for the steam cracker with no outgassing of under ambient pressure.

[0161] The gaseous stream S13 leaves the distillation unit DU as a head product and comprises at least one of the following gases: H2, CH4, C2H6, C3H8, H2S, NH3, HF, HCI, HBr, HI.

[0162] The stabilized product stream S12 leaves the distillation unit DU as a second product stream and is suited as a steam cracker feedstock.

[0163] The distillation unit DU can be for example at least one distillation column, at least one thin film evaporator or a combination thereof. Preferably, in case the distillation unit DU comprises one distillation column. Said one distillation column can also be a dividing-wall column or a column with liquid or vapor side stream. The distillation DU preferably comprises at least one inlet and at least one outlet which is a head outlet.

[0164] The distillation unit DU is downstream of and fluidically connected to the separation unit SU.

[0165] In case the distillation unit DU comprises one column, the stabilized product stream S12 preferably leaves said column as a liquid side stream. In case the distillation unit DU comprises two columns, the stabilized product stream S12 preferably leaves the second column over-head, i.e., as head product.

[0166] The distillation is carried out at a temperature in the range of about 0 °C to about 600 °C, more preferably from about 20 °C to about 400 °C, most preferably from about 80 °C to about 250 °C (the temperature ranges refer to atmospheric pressure of 1.013 bar). The corresponding operating pressure of the at least one distillation column preferably ranges from about 0.1 bar (abs.) to about 20 bar (abs.), more preferably from about 0.5 bar to about 16 bar (abs.), most preferably from about 1 bar to about 14 bar (abs.). The temperature is adjusted accordingly in case the pressure is + 1.013 bar.

[0167] In optional step xiv) stream S12 is converted by steam cracking into a C2-C4 olefin and / or stream S4 is converted by a partial oxidation reaction into a mixture of CO and H2.

[0168] The liquid stream S4 which comprises the portion of liquid stream S1 which is not evaporated in the evaporation unit EU can be for example converted in at least one partial oxidation reaction unit POU into syngas which comprises a mixture of H2, CO and CO2. Such partial oxidation reactions are known in the art and are for example disclosed in Ullmann's Encyclopedia of Industrial Chemistry, Vol. 16, Chapter: Gas Production, 2. Processes”, pages 443-455, 2012 which is incorporated herein by reference. The skilled person can select suitable reactors and reaction conditions to convert the liquid stream S4 into syngas by a partial oxidation reaction and / or gasification. The optional partial oxidation unit POU is preferably located downstream of the evaporation unit EU and fluidically connected to stream S4.

[0169] The stream S12 can be further used as a feedstock in a cracking process, preferably a steam cracking process and is thereby converted into a stream comprising at least one olefin and / or at least one C6-C8 aromatic hydrocarbon, the at least one olefin is preferably selected from the group consisting of ethene, propene, n-butene, 2-butene and butadiene. The steam cracking process is preferably conducted in a steam cracking unit SCU. Steam cracking processes and steam cracking units SCU are for example described in H. Zimmermann, R. Walzl, Ullmann's Encyclopedia of Industrial Chemistry, chapter "Ethylene”, Vol. 13, 2013, pages 469 to 515. The optional steam cracking unit SCU is preferably located downstream of and fluidically connected to the at least one head outlet of the optional distillation unit DU.

[0170] The present invention is further illustrated by the following set of embodiments and combinations of embodiments resulting from the dependencies and back-references as indicated. In particular, it is noted that in each instance where a range of embodiments is mentioned, for example in the context of a term such as "The method of any of embodiments 1 to 3", every embodiment in this range is meant to be explicitly disclosed for the skilled person, i.e. the wording of this term is to be understood by the skilled person as being synonymous to "The method of any of embodiments 1, 2 and 3". Further, it is explicitly noted that the following set of embodiments represents a suitably structured part of the general description directed to preferred aspects of the present invention, and thus, suitably supports the claims of the present invention.

[0171] 1. Method for separating a steam cracker feedstock from a feedstock stream comprising at least one plastic pyrolysis oil, the method comprising the steps

[0172] (I) providing a liquid stream S1 comprising at least one plastic pyrolysis oil, the liquid stream S1 further comprising organic compounds comprising at least one heteroatom and compounds comprising C-C double and / or C-C triple bonds,

[0173] (ii) providing a stream S2, the stream S2 comprising hydrogen,

[0174] (ill) evaporating at least a portion of the liquid stream S1 in the presence of the stream S2 and a recycle gas stream S11 in an evaporation unit EU and thereby forming a gaseous stream S3 which comprises the evaporated portion of the liquid stream S1 , and a liquid stream S4 which comprises the portion of liquid stream S1 which is not evaporated in the evaporation unit EU,

[0175] (iv) optionally superheating the gaseous stream S3 in a superheater SH and thereby form a superheated stream S5,

[0176] (v) feeding the gaseous stream S3 or, optionally the superheated stream S5 into a first hydrogenation unit HU1 in which at least a portion of the gaseous stream S3 or, optionally at least a portion of the superheated stream S5 is converted into a stream S6, wherein the stream S6 is depleted in compounds comprising C-C double and / or C-C triple bonds in respect to gaseous stream S3, (vi) heating the gaseous stream S6 in at least one heating device HD and thereby forming a heated gaseous stream S7,

[0177] (vii) subjecting the heated gaseous stream S7 to a second hydrogenation unit HU2 in which a product stream S8 is formed, wherein the product stream S8 is depleted in organic compounds comprising at least one heteroatom in respect to gaseous stream S6,

[0178] (viii) optionally transferring heat from the product stream S8 to the gaseous stream S3 in the superheater SH and thereby forming a cooled down product stream S8b,

[0179] (ix) continuously or discontinuously feeding a washing water stream S15 to the product stream S8 and thereby forming a stream comprising washing water S8a or optionally continuously or discontinuously feeding a washing water stream S15 to the cooled down product stream S8b and thereby forming a cooled down product stream optionally comprising washing water S8c,

[0180] (x) optionally transferring heat from the cooled down product stream comprising washing water S8c to the liquid stream S1 , stream S2 and stream S11 in the evaporation unit EU and thereby forming a further cooled down product stream S8d,

[0181] (xi) condensing the product stream comprising washing water S8a or optionally one of the streams selected from the group consisting of the cooled down product stream S8b, the cooled down product stream optionally comprising washing water S8c, and the further cooled down product stream optionally comprising washing water S8d, in a condensation unit CU and thereby forming a product stream S9, wherein the product stream S9 comprises a liquid phase and a gas phase,

[0182] (xii) separating the liquid product stream S9 in a separation unit SU into a liquid product stream S10, a recycle gas stream S11 and optionally a waste water stream S17 wherein the recycle gas stream S11 comprises hydrogen and wherein at least a portion of the recycle gas stream S11 is fed into the evaporation unit EU,

[0183] (xiii) optionally feeding the refined product stream S10 into a distillation unit DU in which the liquid product stream S10 is separated into a stabilized product stream S12 and a gaseous stream S13 and

[0184] (xiv) optionally converting stream S12 by steam cracking into a C2-C4 olefin and / or converting stream S4 by a partial oxidation reaction into a mixture of CO and H2. Method according to embodiment 1 wherein the at least one plastic pyrolysis oil is manufactured by a pyrolysis of plastic waste. Method according to embodiment 1 or 2 wherein the organic compounds comprising at least one heteroatom are selected from organic compounds comprising at least one of the following heteroatoms: nitrogen, oxygen, sulfur, chlorine, bromine, fluorine, iodine. Method according to any one of embodiments 1 to 3 wherein the at least one plastic pyrolysis oil in the liquid stream S1 has a bromine number of about 2 g Br2 / 100g to about 150 g Br2 / 100g (determined by ASTM 1159) and / or a C5 hydrocarbon content of about 0.03 wt.-% to about 12.2 wt.-% (determined by ASTM D 5134) and / or a naphthalene content of about 0.5 wt.-% to about 18.4 wt.-% (determined by ASTM D 5134) and / or a styrene content of about 0.02 wt.-% to about 29.5 wt.-% (determined by ASTM D 5134) and / or a toluene content of about 4.3 wt.-% to about 71 .5 wt.-% (determined by ASTM D 5134).

[0185] 5. Method according to any one of embodiments 1 to 4 wherein the hydrogen comprised in stream S2 was formed by water electrolysis using electrical energy, said electrical energy preferably generated from renewable sources and / or low-carbon energy sources and / or a methane pyrolysis, preferably a methane pyrolysis using methane from a renewable source.

[0186] 6. Method according to any one of embodiments 1 to 5 wherein the liquid stream S1 , recycle gas stream S11 and the stream S2 are mixed before fed into the evaporation unit EU and / or mixed in the evaporation unit EU.

[0187] 7. Method according to any one of embodiments 1 to 6 wherein the evaporation unit EU comprises at least one device selected from the group comprising stage evaporator, falling film evaporator, pre-evaporator, preferably wherein the evaporation unit EU consists of at least one pre-evaporator and at least one stage evaporator.

[0188] 8. Method according to any one of embodiments 1 to 7 wherein the liquid stream S1 is evaporated with a recycle gas stream S11 which is added to the liquid stream S1 prior and / or during evaporation.

[0189] 9. Method according to any one of embodiments 1 to 8 wherein the liquid stream S4 is converted in at least one gasifier and / or by a partial oxidation reaction unit into syngas.

[0190] 10. Method according to any one of embodiments 1 to 9 wherein superheater SH is preferably a heat exchanger, more preferably a shell and tube heat exchanger or a spiral heat exchanger.

[0191] 11 . Method according to any one of embodiments 1 to 10 wherein the gaseous stream S3 is superheated in a superheater SH to raise the temperature of the gaseous stream S3 preferably by about 2 °C to about 50 °C, more preferably by about 5 °C to about 40 °C and most preferably by about 10 °C to about 30 °C in respect to the temperature at which the gaseous stream S3 leaves the evaporation unit EU.

[0192] 12. Method according to any one of embodiments 1 to 11 wherein the first hydroprocessing unit HU1 comprises at least one heterogeneous catalyst.

[0193] 13. Method according to any one of embodiments 1 to 12 wherein the at least one heterogeneous catalyst is selected from the group comprising or consisting of nickel-molybdenum catalysts and nickel-tungsten catalysts further comprising a support, preferably an inorganic support selected from the group comprising or consisting of silica, alumina, silica-aluminas, magnesia, clays, and mixtures thereof. 14. Method according to any one of embodiments 1 to 13 wherein the process temperature in the first hydroprocessing unit HU 1 preferably ranges from about 140 °C to about 250 °C, more preferably from about 150 °C to about 200 °C and most preferably from about 170 °C to about 190 °C.

[0194] 15. Method according to any one of embodiments 1 to 14 wherein the heated gaseous stream S7 preferably has a temperature in the range of about 200 °C to about 400 °C, more preferably of about 260 °C to about 360 °C and most preferably of about 280 °C to about 340 °C.

[0195] 16. Method according to any one of embodiments 1 to 15 wherein the at least one heating device is selected from the group comprising direct fired heaters, furnaces powered by electrical energy, heat exchangers, and combinations thereof.

[0196] 17. Method according to any one of embodiments 1 to 16 wherein the wherein the second hydroprocessing unit HU2 comprises at least one fixed-bed reactor.

[0197] 18. Method according to any one of embodiments 1 to 17 wherein the second hydroprocessing unit HU2 comprises at least one heterogeneous catalyst, preferably, wherein the at least one hetereogeneous cataylst is selected from the group comprising or preferably consisting of nickel catalysts, nickel-molybdenum catalysts, and nickel-tungsten catalysts and molybdenum catalysts, cobalt-molybdenum catalysts, and cobalt-tungsten catalysts.

[0198] 19. Method according to any one of embodiments 1 to 18 wherein the temperature of the hydrogenation reaction in the second hydroprocessing unit HU2 preferably ranges from about 200 °C to about 400 °C, more preferably from about 250 °C to about 380 °C, most preferably from about 280 °C to about 360 °C.

[0199] 20. Method according to any one of embodiments 1 to 19 wherein the pressure of the hydrogenation reaction in the second hydroprocessing unit HU2 preferably ranges from about 1 bar to about 200 bar, more preferably from about 10 bar to about 150 bar and most preferably from 15 bar to 60 bar and / or the hydrogen partial pressure in front of hydroprocessing unit HU1 ranges from about 5 bar to about 50 bar, more preferably from about 10 to about 30 bar and most preferably from about 14 bar to about 20 bar.

[0200] 21 . Method according to any one of embodiments 1 to 20 wherein the weight hourly space velocity (WHSV) referring the stream S1 and the catalyst in the hydroprocessing unit HU2 preferably ranges from about 0.1 t / (m3Kat / h) to about 5.0 t / (m3Kaf h), more preferably from about 0.5 t / (m3Kat / h) to about 1.0 t / (m3Kat / h).

[0201] 22. Method according to any one of embodiments 1 to 21 wherein the organic compounds comprising at least one heteroatom in stream S8 are depleted in the second hydroprocessing unit HU2. Method according to any one of embodiments 1 to 22 wherein the organic compounds comprising at least one heteroatom in stream S8 are depleted in the second hydroprocessing unit HU2, preferably wherein the organic compounds comprising sulfur in stream S8 are depleted by at least 90 % in respect to stream S1 and / or the organic compounds in stream S8 comprising halogens are depleted by at least 97 % in respect to stream S1 and / or the organic compounds in stream S8 comprising nitrogen are depleted by at least 99 % in respect to stream S1 . Method according to any one of embodiments 1 to 23 wherein the at least one condensation unit CU is selected from the group comprising heat exchangers, with cooling media like air, cooling water, other media with suitable low temperatures. Method according to any one of embodiments 1 to 24 wherein the at least one separation unit SU is selected from the group comprising hydrocyclones, settler tanks, centrifuges, and combination thereof, more preferably from settler tanks and / or centrifuges. Method according to any one of embodiments 1 to 25 wherein the distillation unit DU preferably comprises one distillation column. Method according to any one of embodiments 1 to 25 wherein the distillation in the distillation unit DU is carried out at a temperature in the range of about 0 °C to about 600 °C, more preferably from about 20 °C to about 400 °C, most preferably from about 80 °C to about 250 °C (the temperature ranges referring to atmospheric pressure of 1 .013 bar)a and preferably a pressure in the range of about 0,1 bar (abs.) to about 20 bar (abs.), more preferably from about 0,5 bar to about 16 bar (abs.), most preferably from about 1 bar to about 14 bar (abs.). Method according to any one of embodiments 1 to 27 wherein stream S14 is further subjected to a steam cracking process and / or a partial oxidation process or a gasification process. Chemical plant for separating a steam cracker feedstock from a feedstock stream comprising at least one plastic pyrolysis oil, the chemical plant comprising

[0202] (I) an evaporation unit EU,

[0203] (ii) optionally a superheater SH downstream of the evaporation unit EU,

[0204] (ill) a first hydroprocessing unit HU1, the first hydroprocessing unit HU1 comprising at least one inlet and at least one outlet, the first hydroprocessing unit HU1 downstream of the evaporation unit EU or the optional superheater SH and the at least one inlet of the first hydroprocessing unit HU1 fluidically connected to the evaporation unit EU or the optional superheater SH, (iv) a heating unit HD having at least one inlet and at least one outlet, the heating unit HD downstream of and at least one inlet of the heating unit HD fluidically connected to the at least one outlet of the first hydroprocessing unit HU1,

[0205] (v) a second hydroprocessing unit HU2 having at least one inlet and at least one outlet, the second hydroprocessing unit HU2 downstream of the heating unit HD and the at least one inlet of the hydroprocessing unit HU2 fluidically connected to the at least one outlet of the heating device HD,

[0206] (vi) a condensation unit CU having at least one inlet and at least one outlet, the condensation unit CU downstream of the second hydroprocessing unit HU2 and the at least one inlet of the condensation unit CU fluidically connected to the at least one outlet of the second hydroprocessing unit HU2,

[0207] (vii) a separation unit SU having at least one inlet and at least one outlet, the separation unit SU downstream of and the at least one inlet of the separation unit SU fluidically connected to the at least one outlet of the condensation unit CU and

[0208] (viii) optionally a distillation unit DU comprising at least one inlet and at least one outlet which is a head outlet, the optional distillation unit DU downstream of and the at least one inlet of the optional distillation unit DU fluidically connected to the at least one outlet of the separation unit SU, optionally a steam cracking unit SCU, downstream of and fluidically connected to the at least one head outlet of the optional distillation unit DU.

[0209] 30. Use of a chemical plant according to embodiment 29 for the method according to any one of embodiments 1 to 28.

[0210] 31 . A computer program comprising instructions which, when the program is executed by the chemical plant according to embodiment 29, cause the system to perform the method according to any one of embodiments 1 to 28.

[0211] It is explicitly noted that the above set of embodiments represents a suitably structured part of the general description directed to preferred aspects of the present invention, and thus, suitably supports, but does not represent the claims of the present invention.

[0212] The invention further relates to a method according to the method described herein, comprising the further step:

[0213] (xv) converting the stream S4 and / or the stream S12 obtainable by or obtained by a process described herein and / or any other chemical material obtainable by or obtained by a process as described herein to obtain a monomer, polymer or polymer product.

[0214] The converting step(s) to obtain the chemical material, 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, ..Kunststoffhand- buch", 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 (A1), EP1460094 (A1), W02006034800 (A1 ), EP 1529792 (A1), W02006042674 (A1), EP0364854 (A2), US5506275 (A), EP0897402 (A1), WO2015082316 (A1), WO2021021855 (A1), WO2021126938 (A1), W02021021902 (A1), W02021092311 (A1), W02008155271 (A1), WO2013139827 (A1), each of which is incorporated herein by reference.

[0215] 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 (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'-dichlorodiphenyl sulfone.

[0216] 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- 1,4-isoprene), poly(trans-1 ,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.

[0217] In a preferred embodiment, the polymer and / or the polymer product is / are then converted into or is / are then converted into 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.

[0218] In a preferred embodiment, the content of the stream S1 in the monomer, polymer 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 stream S1 in the monomer, polymer 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.

[0219] The invention will be further explained by the following non-limiting examples. Examples

[0220] Methods for separating a steam cracker feedstock from a feedstock stream comprising a plastic pyrolysis oil (comparative example and method according to the present invention) were simulated using ASPEN Plus™ V11 simulation software in combination with a kinetic model to calculate the conversion in the first hydroporcessing unit HU1 and the second hydroprocessing HU2.

[0221] Comparative example

[0222] The comparative example is a method and a chemical plant for manufacturing a hydrocarbon feed for steam cracking with a specified boiling range from a plastic pyrolysis oil obtained by pyrolysis of plastic waste and schematically shown in Figure 1. The method reflects those disclosed in AU 2021 / 222788 A1 and FR3118629A1 .

[0223] The process conditions used for the first hydroprocessing unit HU1 are summarized in Table 1 :

[0224] he chosen compositions for the streams S1 , S1 S6, S8, S12, S13 are summarized in Table 2:

[0225] The composition of the liquid stream S1 of the hydroprocessing unit HU1 is described in Tab. 2 with a dienic components concentration of 1.55 wt.-% and olefinic components concentration of 15.26 wt.%. The composition of the liquid stream S1 is identic to the liquid stream S1 used in the example according to the invention below. The liquid stream S1 is processed in the hydroprocessing unit HU1 with conditions described in Tab. 1. The chosen compositions for streams S1 , S1 S6, S8, S12, S13 are summarized in Table 2.

[0226] The catalyst in the hydroprocessing unit HU 1 is a Ni-Mo catalyst on an alumina support.

[0227] The pressure at reactor outlet of the first hydroprocessing unit HU 1 is 64 bar (abs.) and the reactor temperature rises from 118 °C (reactor inlet temperature) to 150 °C (reactor outlet temperature) by adiabatic temperature increase. Under these conditions typical trickle-bed flow of the liquid phase over the (solid) catalyst occurs which is desired.

[0228] The ratio "liquid feed S1 : liquid recycle stream S11” from the hydroprocessing unit HU2 (Figure 1) is 1 : 1. Hence, the concentration of dienic components with 1.13 mole.-% in the reactor inlet stream of HU1 is a factor of 4.3 higher than the concentration of dienic components in the example according to the present invention (see below stream S3) in the reactor inlet stream ST. The temperature increase of 32 °C (from the reactor inlet to reactor outlet of the first hydroprocessing unit HU1) is slightly higher in comparison to 21 °C in the example according to the present invention (see below). The much higher dienic components concentration in comparison to the present invention (see below) causes a higher polymer formation potential during processing and so advances plugging which are both undesired. A typical value to evaluate the efficiency of such a selective hydrogenation is the conversion of styrene to ethylbenzene. Under these conditions a sufficient per-pass conversion of < 80 % (83 %) is achieved.

[0229] The WHSV (weight hourly space velocity) of liquid stream S1 is 0.5 t / (m3Kat *h). The chemical hydrogen consumption in the hydroprocessing unit HU1 is 25 Nm3 / t. The molar ratio "stream S2 fed to the hydroprocessing unit HU1 : chemical hydrogen consumption” is 1.08 : 1 . The small excess of hydrogen assures the sufficient activity of the catalyst to effect 83 % conversion of the dienic components and 59 % conversion of the olefinic components (stream S3). Under these operation conditions and the catalyst used (Ni-Mo catalyst on an alumina support), no hydrogenation of the aromatic components will occur. The reactor product of hydroprocessing unit HU1 (stream S6 in Fig. 1) is directly fed to the hydroprocessing unit HU2.

[0230] The process conditions in the second hydroprocessing unit HU2 are summarized in Table 3: The pressure at reactor outlet is 63 bar (abs.). The ratio "HU2 internal recycle-gas S6" : feed stream S6” is 400 Nm3 / t and the reactor inlet temperature of the second hydroprocessing unit HU2 is 300 °C. Under these conditions, the feed stream S6 of the hydroprocessing unit HU2 is partly evaporated.

[0231] Caused by the low content of dienic components of < 0.2 wt.-% in the feed stream S3 of the hydroprocessing unit HU2 no undesired polymerization and fouling occurs during partial evaporation. The reactor temperature rises from an inlet temperature of 300 °C to an outlet temperature of 314 °C by the exotherm hydrogenation reactions mentioned above. The temperature rise is 19 °C because 59 % of the olefins are already hydrogenated in the hydroprocessing unit HU1 and the 1 : 1 dilution by the "liquid feed S1 : liquid recycle stream S11” from the hydroprocessing unit HU2.

[0232] The hydrogen partial pressure at the outlet the reactor of 43 bar (abs.) is sufficient to assure a sufficient hydrogenation activity for HDH, HDN and HDS reactions. The catalyst in the hydroprocessing unit HU2 is a standard Ni-Mo catalyst on an alumina support which shows sufficient dienic- and olefinic-hydrogenation, hydrodesulfurization (HDS), hydrodenitration (HDN) and hydrodehalogenation (HDH) activity. The WHSV of the feed stream S6 is 0.7 t / (m3Kat*h). The reaction product stream S8 of HU2 shows a sulfur content lower than 50 wt.-ppm, a nitrogen content of lower than 10 wt.-ppm and a chlorine content lower than 1 wt.-ppm.

[0233] The cooled down condensed liquid reaction product S8 leaving the second hydroprocessing unit HU2 is fed with a ratio of 1 : 1 together with the liquid feed stream S1 back to the hydroprocessing unit HU1 to dilute the liquid feed stream S1 bevor entering the first hydroprocessing unit HU1 . The necessity and effect of the dilution is described above for the hydroprocessing unit HU1.

[0234] In the following distillation unit DU, the dissolved gases (H2, CH4, C2H6, C3H8, H2S and NH3) are separated as stream S13 from the valued product fraction (stream S12). So, the light boiling components are removed to obtain a stable feed for the steam cracker with no outgassing under ambient pressure. The off-gas, stream S13, of the distillation unit DU is 6 Nm3 / t. The product stream S12 needs no further distillation with a final boiling point of 232°C and is ready for feeding in a steam cracker.

[0235] Example (invention)

[0236] The method according to the present invention was simulated in this example following the schematic representation in Figure 2.

[0237] The process conditions in the evaporation section EU are summarized in Table 4: he chosen compositions for the streams S1 , S3, S4, S6, S8, S10, S12, S13 are summarized in Table 5:

[0238] The composition of the liquid stream S1 of the hydroprocessing unit HU1 is described in Tab. 5 with a dienic components concentration of 1.55 wt.-% and olefinic components concentration of 15.26 wt.-%. The composition of the liquid stream S1 is identic to the liquid stream S1 used in the comparative example above.

[0239] The liquid stream S1 is processed in the evaporation section EU. The stream S1 is evaporated in the mixture of the fresh H2 steam S2 and the recycle gas stream S11 of 1545 Nm3 / t stream S1. The resulting saturated vapor mixture stream S3 have a dew point of 190 °C at 20.7 bar (abs.). 98.3 wt.-% of the feed stream S1 are evaporated. The residue (stream S4) has a boiling range of 108°C to 305°C.

[0240] In the following super heater SU the saturated vapor phase stream S3 is superheated by 10 °C to a temperature of 200 °C to ensure no liquid entrainment is still existent an no condensation occurs by heat-loss in the chemical plant.

[0241] The process conditions in the first hydroprocessing unit HU 1 are summarized in Table 6:

[0242] The catalyst in the first hydroprocessing unit HU 1 is a Ni-Mo catalyst on an alumina support which allows the pointed- out reaction conditions in the vapor phase. With 87.3 vol.-% H2 at 20.6 bar (abs.) the inlet stream H2 partial pressure of the first hydroprocessing unit HU 1 is 18 bar (abs.). This hydrogen partial pressure is sufficient to ensure a high hydrogenation activity and well selectivity of the catalysts in the first and second hydroprocessing units HU 1 and HU2.

[0243] The pressure at the reactor inlet is 20.6 bar (abs.) in the first hydroprocessing unit HU 1 and the reactor temperature rises from 200 °C reactor inlet temperature to 221 °C reactor outlet temperature by adiabatic temperature increase.

[0244] The dilution in the inlet stream S1 with fresh H2 stream S2 and recycle gas stream S11 affects a low dienic components concentration of 0.26 mol-% and olefinic components content of 1.64 mol-%. In the comparative example the dienic components molar concentration is 4.3 times higher. The high dilution in the gas phase pressure together with the low dienic components concentration assures the avoidance of undesired polymer formation and fouling during processing.

[0245] The reactor of the hydroprocessing unit HU 1 is operated in up-flow mode. Accordingly, stream S5 enters the at least one reactor of the first hydroprocessing unit HU 1 in the bottom area of said at least one reactor and leaves said at least one reactor as stream S6 in the top section of said at least one reactor. The WHSV (weight hourly space velocity) of the liquid stream S1 is 2.0 t / (m3Kat*h). The chemical hydrogen consumption in the first hydroprocessing unit HU 1 is 17 Nm3 / t. Under these conditions 84 % conversion of the dienic components and 32 % conversion of the olefinic components (stream S3) and no hydrogenation of the aromatic components will occur.

[0246] A typical value to evaluate the efficiency of such a selective hydrogenation is the conversion of styrene to ethylbenzene. Under these conditions a sufficient per-pass conversion of < 80 % (83 %) is achieved.

[0247] The stream S6 leaving the first hydrogenation unit HU1 is stable enough (no undesired fouling by polymerization will occur) to be heated up in the heating device HD to 310 °C, which is then the reactor inlet temperature of the second hydroprocessing unit HU2.

[0248] The process conditions of the second hydroprocessing unit HU2 are shown in Table 7:

[0249] Here the remaining small amounts of dienic and olefinic components are hydrogenated in the gas-phase to the corresponding saturated hydrocarbons. The sulfur containing components are hydrogenated to the corresponding saturated hydrocarbons and H2S. The sulfur content in the hydroprocessed product stream S6 is < 50 wt.-ppm. The nitrogen containing components are hydrogenated to the corresponding saturated hydrocarbons and NH3. The nitrogen content in the hydroprocessed product stream S6 is < 10 wt.-ppm The halogen-, like chlorine-containing components are hydrogenated to the corresponding saturated hydrocarbons and hydrohalogenic acids such as HCI. The halogens / chlorine content in the hydroprocessed product stream S6 is < 1 wt.-ppm.

[0250] The pressure at reactor inlet is 20.3 bar (abs.). The reactor inlet temperature is 310 °C. Under these conditions, the inlet stream S7 of the second hydroprocessing unit HU2 is complete (as desired) in the vapor phase. Caused by the low content of dienic components of < 0.04 mole.-% in the feed stream S7, no undesired polymerization and fouling occurs during inside the second hydroprocessing unit HU2. The reactor temperature rises from 310 °C inlet temperature to 338 °C outlet temperature by the exotherm hydrogenation reactions. The hydrogen partial pressure in the reactor of the second hydroprocessing unit HU2 of 17.7 bar (abs.) is suited to assure a sufficient hydrogenation activity but to avoid the undesired hydrogenation of aromatic hydrocarbons. The catalyst in the second hydroprocessing unit HU2 is a Ni-Mo catalyst on an alumina support which shows sufficient dienic- and olefinic-hydrogenation, desulfurization, denitration and dehalogenation activity. The WHSV of stream S1 is 0.7 t / (m3Kat*h).

[0251] After leaving the reactor the product stream is successively cooled down, the valued product containing stream S10 is separated from the recycle gas stream S11 .

[0252] In the following distillation unit DU, the dissolved gases (H2, CH4, C2H6, C3H8, H2S and NH3) are separated as stream S13 from the valued product fraction (stream S12).

[0253] So, the light boiling components are removed to obtain a stable feed for the steam cracker with no outgassing of under ambient pressure.

[0254] The off-gas, stream S13, of the distillation unit DU is 9 Nm3 / t.

[0255] The product stream S12 needs no further distillation with a final boiling point of 255 °C and is ready for feeding in a steam cracker.

Claims

Claims1. Method for separating a steam cracker feedstock from a feedstock stream comprising at least one plastic pyrolysis oil, the method comprising the steps(I) providing a liquid stream S1 comprising at least one plastic pyrolysis oil, the liquid stream S1 further comprising organic compounds comprising at least one heteroatom and compounds comprising C-C double and / or C-C triple bonds,(ii) providing a stream S2, the stream S2 comprising hydrogen,(ill) evaporating at least a portion of the liquid stream S1 in the presence of the stream S2 and a recycle gas stream S11 in an evaporation unit EU and thereby forming a gaseous stream S3 which comprises the evaporated portion of the liquid stream S1 , and a liquid stream S4 which comprises the portion of liquid stream S1 which is not evaporated in the evaporation unit EU,(iv) optionally superheating the gaseous stream S3 in a superheater SH and thereby form a superheated stream S5,(v) feeding the gaseous stream S3 or, optionally the superheated stream S5 into a first hydrogenation unit HU1 in which at least a portion of the gaseous stream S3 or, optionally at least a portion of the superheated stream S5 is converted into a stream S6, wherein the stream S6 is depleted in compounds comprising C-C double and / or C-C triple bonds in respect to gaseous stream S3,(vi) heating the gaseous stream S6 in at least one heating device HD and thereby forming a heated gaseous stream S7,(vii) subjecting the heated gaseous stream S7 to a second hydrogenation unit HU2 in which a product stream S8 is formed, wherein the product stream S8 is depleted in organic compounds comprising at least one heteroatom in respect to gaseous stream S6,(viii) optionally transferring heat from the product stream S8 to the gaseous stream S3 in the superheater SH and thereby forming a cooled down product stream S8b,(ix) continuously or discontinuously feeding a washing water stream S15 to the product stream S8 and thereby forming a stream comprising washing water S8a or optionally continuously or discontinuously feeding a washing water stream S15 to the cooled down product stream S8b and thereby forming a cooled down product stream optionally comprising washing water S8c,(x) optionally transferring heat from the cooled down product stream comprising washing water S8c to the liquid stream S1, stream S2 and stream S11 in the evaporation unit EU and thereby forming a further cooled down product stream S8d,(xi) condensing the product stream comprising washing water S8a or optionally one of the streams selected from the group consisting of the cooled down product stream S8b, the cooled down product stream optionally comprising washing water S8c, and the further cooled down product stream optionally comprising washing water S8d, in a condensation unit CU and thereby forming a product stream S9, wherein the product stream S9 comprises a liquid phase and a gas phase,(xii) separating the liquid product stream S9 in a separation unit SU into a liquid product stream S10, a recycle gas stream S11 and optionally a waste water stream S17 wherein the recycle gas stream S11 comprises hydrogen and wherein at least a portion of the recycle gas stream S11 is fed into the evaporation unit EU,(xiii) optionally feeding the refined product stream S10 into a distillation unit DU in which the liquid product stream S10 is separated into a stabilized product stream S12 and a gaseous stream S13 and(xiv) optionally converting stream S12 by steam cracking into a C2-C4 olefin and / or converting stream S4 by a partial oxidation reaction into a mixture of CO and H2.

2. Method according to embodiment 1 wherein the at least one plastic pyrolysis oil is manufactured by a pyrolysis of plastic waste.

3. Method according to claim 1 or 2 wherein the organic compounds comprising at least one heteroatom are selected from organic compounds comprising at least one of the following heteroatoms: nitrogen, oxygen, sulfur, chlorine, bromine, fluorine, iodine.

4. Method according to any one of claims 1 to 3 wherein the at least one plastic pyrolysis oil in the liquid stream S1 has a bromine number of about 2 g Br2 / 100g to about 150 g Br2 / 100g (determined by ASTM 1159) and / or a C5 hydrocarbon content of about 0.03 wt.-% to about 12.2 wt.-% (determined by ASTM D 5134) and / or a naphthalene content of about 0.5 wt.-% to about 18.4 wt.-% (determined by ASTM D 5134) and / or a styrene content of about 0.02 wt.-% to about 29.5 wt.-% (determined by ASTM D 5134) and / or a toluene content of about 4.3 wt.-% to about 71.5 wt.-% (determined by ASTM D 5134).

5. Method according to any one of claims 1 to 4 wherein the hydrogen comprised in stream S2 was formed by water electrolysis using electrical energy from renewable sources and / or a methane pyrolysis, preferably a methane pyrolysis using methane from a renewable source.

6. Method according to any one of claims 1 to 5 wherein the evaporation unit EU comprises at least one device selected from the group comprising stage evaporator, falling film evaporator, pre-evaporator, preferably wherein the evaporation unit EU consists of at least one pre-evaporator and at least one stage evaporator.

7. Method according to any one of claims 1 to 6 wherein the liquid stream S1 is evaporated with a recycle gas stream S11 which is added to the liquid stream S1 prior and / or during evaporation.

8. Method according to any one of claims 1 to 7 wherein the first hydroprocessing unit HU1 comprises at least one heterogeneous catalyst.

9. Method according to any one of claims 1 to 8 wherein the at least one heterogeneous catalyst is selected from the group consisting of nickel-molybdenum catalysts and nickel-tungsten catalysts further comprising a support, preferably an inorganic support selected from the group comprising silica, alumina, silica-aluminas, magnesia, clays, and mixtures thereof.

10. Method according to any one of claims 1 to 9 wherein the process temperature in the first hydroprocessing unit HU 1 preferably ranges from about 140 °C to about 250 °C, more preferably from about 150 °C to about 200 °C and most preferably from about 170 °C to about 190 °C11 . Method according to any one of claims 1 to 10 wherein the second hydroprocessing unit HU2 comprises at least one heterogeneous catalyst, preferably, wherein the at least one hetereogeneous cataylst is selected from the group consisting of molybdenum catalysts, cobalt-molybdenum catalysts, and cobalt-tungsten catalysts.

12. Method according to any one of claims 1 to 11 wherein the weight hourly space velocity (WHSV) referring the feed stream S1 preferably ranges from about 0.1 t / (m3Kat / h) to about 5.0 t / (m3Kat h), more preferably from about 0.5 t / (m3Kat / h) to about 1.0 t / (m3Kat / h).

13. Method according to any one of claims 1 to 12 wherein the organic compounds comprising at least one heteroatom in stream S8 are depleted in the second hydroprocessing unit HU2, preferably wherein the organic compounds comprising sulfur in stream S8 are depleted by at least 90 % in respect to stream S1 and / or the organic compounds in stream S8 comprising halogens are depleted by at least 97 % in respect to stream S1 and / or the organic compounds in stream S8 comprising nitrogen are depleted by at least 99 % in respect to stream S1 .

14. Method according to any one of claims 1 to 13 comprising the further step(xv) converting a stream S4 and / or a stream S12 obtainable by or obtained by the process according to claim 1 and / or any other chemical material obtainable by or obtained by a process according to any one of the foregoing claims to obtain a monomer, polymer or polymer product.

15. Method according to claim 14 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'-dichlorodiphenyl sulfone.

16. Method according to claim 14 or 15 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-1 ,4-isoprene), poly(trans-1,4-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.

17. Method according to any one of claims 14 to 16 wherein the polymer and / or the polymer product is / are then converted into or is / are then converted into 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 bottlefor 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 multilayer), 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.

18. Method according to any one of claims 14 to 17 wherein the content of the stream S1 in the monomer, polymer 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 stream 1 in the monomer, polymer 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.

19. Chemical plant for separating a steam cracker feedstock from a feedstock stream comprising at least one plastic pyrolysis oil, the chemical plant comprising(I) an evaporation unit EU(II) optionally a superheater SH downstream of the evaporation unit EU,(ill) a first hydroprocessing unit HU1, the first hydroprocessing unit HU1 comprising at least one inlet and at least one outlet, the first hydroprocessing unit HU1 downstream of the evaporation unit EU or the optional superheater SH and the at least one inlet of the first hydroprocessing unit HU1 fluidically connected to the evaporation unit EU or the optional superheater SH,(iv) a heating unit HD having at least one inlet and at least one outlet, the heating unit HD downstream of and at least one inlet of the heating unit HD fluidically connected to the at least one outlet of the first hydroprocessing unit HU1,(v) a second hydroprocessing unit HU2 having at least one inlet and at least one outlet, the second hydroprocessing unit HU2 downstream of the heating unit HD and the at least one inlet of the hydroprocessing unit HU2 fluidically connected to the at least one outlet of the heating device HD,(vi) a condensation unit CU having at least one inlet and at least one outlet, the condensation unit CU downstream of the second hydroprocessing unit HU2 and the at least one inlet of the condensation unit CU fluidically connected to the at least one outlet of the second hydroprocessing unit HU2,(vii) a separation unit SU having at least one inlet and at least one outlet, the separation unit SU downstream of and the at least one inlet of the separation unit SU fluidically connected to the at least one outlet of the condensation unit CU and(viii) optionally a distillation unit DU comprising at least one inlet and at least one outlet which is a head out- let, the optional distillation unit DU downstream of and the at least one inlet of the optional distillation unit DU fluidically connected to the at least one outlet of the separation unit SU, optionally a steam cracking unit SCU, downstream of and fluidically connected to the at least one head outlet of the optional distillation unit DU.

20. Use of a chemical plant according to claim 19 for the method according to any one of claims 1 to 18.

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