Manufacture of ethylene-derived chemicals having a bio-based carbon content from bio-naphtha

Abstract

A process for the manufacture of one or more ethylene-derived chemical(s) having a bio- based carbon content comprises the steps of (a) providing a first ethylene stream by (a-i) providing a cracker feed stream containing bio-naphtha and fossil-based hydrocarbons, (a-ii) subjecting the cracker feed to steam cracking to obtain a cracker effluent, (a-iii) recovering from the cracker effluent the first ethylene stream; (b) providing a second ethylene stream having a bio-based carbon content; (c) combining the first ethylene stream and the second ethylene stream to obtain a combined ethylene stream; (d) converting the combined ethylene stream to at least a first generation ethylene-derived chemical selected from (α) ethylene oxide, (β) ethylbenzene, (y) ethylene dichloride; and (δ) propionaldehyde; and (e) optionally subjecting the first generation ethylene-derived chemical to a chemical conversion or a sequence of chemical conversions to obtain a downstream ethylene-derived chemical. The process allows for efficient operation of the steam cracker while allowing for the production of ethylene-derived chemicals with a predetermined bio-based carbon content.

Description

[0001] Manufacture of Ethylene-Derived Chemicals Having a Bio-Based Carbon Content From Bio-Naphtha

[0002] The invention relates to a process for the manufacture of one or more ethylene-derived chemical(s) having a bio-based carbon content.

[0003] Chemical recycling aims to convert plastic waste into chemicals. It is a process where the chemical structure of the polymer is changed and converted into chemical building blocks including monomers that are then used again as a raw material in chemical processes. Through a pyrolysis process, waste plastics can be converted to gas and liquid products. These liquid products contain paraffins, iso-paraffins, olefins, naphthenes, and aromatic components. As such, the liquid products of a pyrolysis process (pyrolysis oils) can be used as a feedstock for steam crackers.

[0004] Ethylene is a key building block in the chemical industry. A major route for ethylene production is based on the cracking of hydrocarbons, for example steam cracking. Important ethylene derivatives (at the end of their respective chains) include (meth)acrylic acid, (meth)acrylic esters, isononanol, ethylhexanol, and ethylene glycols. One of the problems faced by the manufacture of chemicals and intermediates from ethylene is that the starting raw materials are from fossil fuels, such as natural gas or crude oil, which are non-renewable feedstocks.

[0005] Extensive efforts have been taken in recent years to increase the sustainability of cracker products. One approach is the partial substitution of fossil based hydrocarbons such as naphtha by pyrolysis oil or bio-naphtha.

[0006] The use of co-feeds derived from pyrolysis oil that is obtained from the pyrolysis of recycled plastic waste is disclosed in WO 2022 / 067251 A1. The production of ethylenederived products such as alkylene oxides and alkanolamines based on pyrolysis of a recycled waste is disclosed in WO 2021 / 092320 A1. The combination of renewable raw materials and / or recycled raw materials into a mainstream of conventional raw materials originated from petroleum, the conversion of such streams to ethylene and the manufacture of specific dialkylphosphinic salts being produced from such ethylene is disclosed in WO 2023 / 280613 A1 (Clariant). The production of bio-naphtha is for instance disclosed in US 2012 / 0053379 A1 (Stora Enso), along with subjecting the hydrocarbons to steam cracking to obtain inter alia ethylene and to produce ethylene derivatives therefrom.

[0007] The demand for ethylene-derived chemicals having a certain bio-based carbon content has been increasing throughout the last decade and is expected to further increase. One way to achieve such increased bio-based carbon content is the development of alternative synthesis routes based on bio-feedstocks. This approach comes with certain drawbacks. In many cases the synthesis route deviates significantly from the well- established fossil-based manufacturing route. Thus, the existing productions facilities cannot be used, but new ones would have to be built which is economically, environmentally, and technically challenging. Moreover, the chemical industry, currently using naphtha and methane as its major carbon sources, would have to change to an economy that is based on a variety of different feedstocks increasing the complexity of chemical production.

[0008] As stated above, the technical possibilities of increasing the bio-based carbon content in cracker products (ethylene) is limited. Therefore, there is a need for a process which allows for efficient operation of the steam cracker while allowing for the production of ethylene-derived chemicals with a predetermined bio-based carbon content.

[0009] The invention relates to a process for the manufacture of one or more ethylene-derived chemical(s) having a bio-based carbon content, the process comprising the steps of:

[0010] (a) providing a first ethylene stream by

[0011] (a-i) providing a cracker feed stream containing bio-naphtha and fossil-based hydrocarbons,

[0012] (a-ii) subjecting the cracker feed to steam cracking to obtain a cracker effluent, (a-iii) recovering from the cracker effluent the first ethylene stream;

[0013] (b) providing a second ethylene stream having a bio-based carbon content by subjecting a feedstock comprising bioethanol to dehydration;

[0014] (c) combining the first ethylene stream and the second ethylene stream to obtain a combined ethylene stream;

[0015] (d) converting the combined ethylene stream to at least a first generation ethylenederived chemical selected from

[0016] (a) ethylene oxide,

[0017] (P) ethylbenzene,

[0018] (y) ethylene dichloride; and

[0019] (5) propionaldehyde; and

[0020] (e) optionally subjecting the first generation ethylene-derived chemical to a chemical conversion or a sequence of chemical conversions to obtain a downstream ethylene-derived chemical.

[0021] According to the invention, a cracker-based ethylene stream (first ethylene stream) is combined with an ethylene stream having a known bio-based carbon content (second ethylene stream). By the combination of the ethylene streams one obtains an ethylene stream having a defined amount of bio-based carbon that may be adjusted by varying the blending ratio of the two ethylene streams, thereby enabling the downstream production of ethylene-derived products having a predetermined bio-based carbon content. By using a second ethylene stream high in bio-based carbon content, the combined ethylene stream has a defined minimum bio-based carbon content, and thus a minimum bio-based carbon content in any downstream cracker-based ethylenederived product can be guaranteed. To define more clearly the terms used herein, the following definitions are provided, and unless explicitly provided otherwise are applicable throughout this disclosure.

[0022] The terms “renewable" or “renewably-sourced" in relation to a chemical compound are used synonymously and mean a chemical compound comprising a quantity of renewable carbon, i.e. , having a reduced or no carbon content of fossil origin. Renewable carbon entails all carbon sources that avoid or substitute the use of any additional fossil carbon from the geosphere. Renewable carbon can come from the biosphere, atmosphere or technosphere - but not from the geosphere. Thus, the expression “renewable” or “renewably-sourced” includes, in particular, biomass-derived chemical compounds. It also includes compounds derived from waste such as polymer residues, or from waste streams of chemical production processes.

[0023] The term “bio-based” means containing organic carbon of renewably origin like agricultural, plant, animal, fungi, microorganisms, marine, or forestry materials living in a natural environment in equilibrium with the atmosphere.

[0024] The term “bio-based carbon content” means the amount of bio-based carbon in the material or product as a percentage of the total organic carbon (TOC) in the material or product.

[0025] The bio-based carbon content of a material may be measured using the ASTM D6866 method, which allows the determination of the bio-based content of materials using radiocarbon analysis by accelerator mass spectrometry, liquid scintillation counting, and isotope mass spectrometry. When nitrogen in the atmosphere is struck by an ultraviolet light produced neutron, it loses a proton and forms carbon that has a molecular weight of 14, which is radioactive. This14C is immediately oxidized into carbon dioxide, and represents a small, but measurable fraction of atmospheric carbon. Atmospheric carbon dioxide is cycled by green plants to make organic molecules during photosynthesis. The cycle is completed when the green plants or other forms of life metabolize the organic molecules producing carbon dioxide which is then able to return back to the atmosphere. Therefore, the14C that exists in the atmosphere becomes part of all life forms and their biological products.

[0026] The application of ASTM D6866 to derive a “bio-based carbon content” is built on the same concepts as radiocarbon dating, but without use of the age equations. The analysis is performed by deriving a ratio of the amount of radiocarbon (14C) in an unknown sample to that of a modern reference standard. The ratio is reported as a percentage, with the units “pMC” (percent modern carbon). If the material being analyzed is a mixture of present day radiocarbon and fossil carbon (containing no radiocarbon), then the pMC value obtained correlates directly to the amount of bio-based material present in the sample. The modern reference standard used in radiocarbon dating is a NIST (National Institute of Standards and Technology) standard with a known radiocarbon content equivalent approximately to the year AD 1950. The year AD 1950 was chosen because it represented a time prior to thermonuclear weapons testing which introduced large amounts of excess radiocarbon into the atmosphere with each explosion (termed “bomb carbon”). The AD 1950 reference represents 100 pMC. “Bomb carbon” in the atmosphere reached almost twice normal levels in 1963 at the peak of testing and prior to the treaty halting the testing. Its distribution within the atmosphere has been approximated since its appearance, showing values that are greater than 100 pMC for plants and animals living since AD 1950. The distribution of bomb carbon has gradually decreased over time, with today's value being near 107.5 pMC. As a result, a fresh biomass material, such as corn, could result in a radiocarbon signature near 107.5 pMC.

[0027] Petroleum-based carbon does not have the signature radiocarbon ratio of atmospheric carbon dioxide. Research has noted that fossil fuels and petrochemicals have less than about 1 pMC, and typically less than about 0.1 pMC, for example, less than about 0.03 pMC. However, compounds derived entirely from renewable resources have at least about 95 percent modern carbon (pMC), they may have at least about 99 pMC, including about 100 pMC.

[0028] Combining fossil carbon with present day carbon into a material will result in a dilution of the present day pMC content. By presuming that 107.5 pMC represents present day biobased materials and 0 pMC represents petroleum derivatives, the measured pMC value for that material will reflect the proportions of the two component types. A material derived 100% from present day biomass would give a radiocarbon signature near 107.5 pMC. If that material were diluted with 50% petroleum derivatives, it would give a radiocarbon signature near 54 pMC.

[0029] A bio-based content result is derived by assigning 100% equal to 107.5 pMC and 0% equal to 0 pMC. In this regard, a sample measuring 99 pMC will give an equivalent biobased content result of 93%.

[0030] The term “bioethanol” means ethanol obtained from a biomass feedstock, such as plant or non-crop feedstock containing a carbon source that is convertible to ethanol, for example by microbial metabolism.

[0031] A “first generation ethylene-derived chemical” denotes a primary reaction product of ethylene which may be subject to a chemical conversion or a sequence of chemical conversions to obtain a downstream ethylene-derived chemical.

[0032] The term “downstream ethylene-derived chemicals” collectively refers to any desired compound appearing in a value chain starting out from a first generation ethylenederived chemical. Thus, the expression includes any intermediates and final products. In certain cases, a chemical compound can be an intermediate and final product at the same time. First Ethylene Stream

[0033] According to the process of the invention, a first ethylene stream is provided by subjecting a cracker feed stream to steam cracking. From the cracker effluent a first ethylene stream is recovered.

[0034] Cracker Feed Stream

[0035] The cracker feed stream contains bio-naphtha and fossil-based hydrocarbons. In certain embodiments, the cracker feed stream additionally contains pyrolysis oil.

[0036] In an embodiment, cracker feed stream comprises, relative to the total weight of the cracker feed:

[0037] 0.1 to 20 wt.% bio-naphtha; and

[0038] 80 to 99.9 wt.-% fossil-based hydrocarbons; preferably

[0039] 0.1 to 10 wt.% bio-naphtha; and

[0040] 90 to 99.9 wt.-% fossil-based hydrocarbons.

[0041] Fossil-based hydrocarbons being used as a cracker feed are in particular ethane, propane, butane and / or naphtha. Ethane, propane, and butane occur as a component in natural gas and petroleum. Thus, they can be obtained from natural gas processing or petroleum refining, by separation from other hydrocarbons and where required subsequent refining. Naphtha (fossil-based) may originate from upstream refinery processes such as an atmospheric distillation tower, hydrocracker or coker unit. Different types of fossil-based naphtha may be distinguished, e.g., via their boiling point. Thus, “light naphtha” has a boiling point in the range of 30 to 90 °C and comprises a major fraction of molecules with 5 to 6 carbon atoms, whereas “heavy naphtha” has a boiling point in the range of 90 to 200 °C and comprises a major fraction of molecules with 6 to 12 carbon atoms. In an embodiment, the fossil-based naphtha is light naphtha.

[0042] The fossil-based hydrocarbons in the cracker feed stream can be one or a mixture of two or more of ethane, propane, butane, or naphtha. It can also be substantially either of ethane, propane, butane, or naphtha. Preferably the fossil-based hydrocarbons are naphtha.

[0043] In an embodiment, the cracker feed stream comprises, relative to the total weight of the cracker feed, 80 to 99.9 wt.% or 90 to 99 wt.% of fossil-based hydrocarbons. In another embodiment, the cracker feed stream comprises 60 to 99.8 wt.% of fossil-based hydrocarbons. In another embodiment, the cracker feed stream comprises 55 to 99 wt.% of fossil-based hydrocarbons. Bio-Naphtha

[0044] Bio-naphtha may be produced from complex mixtures of fats and oils, such as vegetable oils, industrial fats and waste oils. Thus, bio-naphtha is a renewable source of energy.

[0045] In an embodiment, bio-naphtha may be added to fossil naphtha in order to provide a first ethylene stream having a bio-based carbon content of greater than zero.

[0046] In an embodiment, the bio-naphtha is at least partially obtained from the hydrogenation of fatty acids, fatty acid derivatives, mono-, di- or, triglycerides, or a combination thereof. Bio-naphtha is known as such and its production is, for example, disclosed in US20120053379 A1. The starting material for producing bio-naphtha may be tall oil based. Tall oil is an oil product obtained from wood such as pine and other softwood trees. In general, the starting material comprises at least 75 wt.% of fatty acids of tall oil and no more than 25 wt.% resin acids of tall oil. The starting material may comprise other suitable vegetable oils, e.g. palm oil. The starting material is subjected to hydrodeoxygenation by a method known as such which is, for example described in US20120053379 A1. The hydrodeoxygenation product is a hydrocarbon mixture which suitable to be subjected to steam cracking.

[0047] In an embodiment, the cracker feed stream comprises, relative to the total weight of the cracker feed stream, up to 10 wt.% bio-naphtha. In another embodiment, the cracker feed stream comprises, relative to the total weight of the cracker feed stream, 0.1 to 10 wt.% bio-naphtha.

[0048] Pyrolysis Oil

[0049] In an embodiment, the cracker feed stream may additionally comprise pyrolysis oil.

[0050] In the context of the present invention, the term “pyrolysis” relates to a thermal decomposition or degradation of end of life solid organic feedstock, such as plastics or rubber, under inert conditions and results in a gas, a liquid and a solid char fraction. During the pyrolysis, the plastics and rubber are converted into a great variety of chemicals including gases such as H2, Ci-C4-alkanes, C2-C4-alkenes, ethyne, propyne, 1-butyne, pyrolysis oil having a boiling temperature of 25 to 500 °C, and char. The term “pyrolysis” includes slow pyrolysis, fast pyrolysis, flash catalysis and catalytic pyrolysis. These types of pyrolysis differ in the process temperature, heating rate, residence time, feed particle size, etc. resulting in different product quality.

[0051] In the context of the present invention, the term “pyrolysis oil” is understood to mean any oil originating from the pyrolysis of waste solid organic feedstock, such as plastic waste or rubber waste.

[0052] 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. 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 has 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. Accordingly the term “plastic waste” includes industrial and domestic plastic waste including used tires and agricultural and horticultural plastic material. The term “plastic waste” also includes used petroleum-based hydrocarbon material such as used motor oil, machine oil, greases, waxes, etc.

[0053] Typically, plastic waste is a mixture of different plastic material, 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., nitrogen-containing plastics, such as polyamides (PA), polyurethanes (Pll), acrylonitrile butadiene styrene (ABS), etc., oxygen-containing plastics such as polyesters, e.g. polyethylene terephthalate (PET), polycarbonate (PC), etc.), silicones and / or rubber, such as sulfur bridges crosslinked rubbers. PET plastic waste is often sorted out before pyrolysis, since PET has a profitable resale value. Accordingly, the plastic waste to be pyrolyzed often contains less than about 10% by weight, preferably less than about 5% by weight and most preferably substantially no PET based on the dry weight of the plastic material. One of the major components of waste from electric and electronic equipment are polychlorinated biphenyls (PCB). 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 amout of less than 50% by weight, preferably less than 30% by weight, more preferably less than 20% by weight, even more preferably less than 10% by weight based on the total weight of the dry weight plastic.

[0054] Depending on the waste plastic material subjected to the pyrolysis, the crude pyrolysis oil may have varying contents of sulfur, nitrogen, halogen and, if present, heavy metal. If desired, pyrolysis oil may be purified prior to its use in a cracker feed stream.

[0055] The term “rubber material” as used herein is meant to indicate a polymeric material that constitutes the elastomeric, partially cross-linked (e.g., vulcanized) polymer materials that may be stretched at room temperature to at least twice their original length and, after having been stretched and the stress removed, returns its force to approximately its original length in a short time. The rubber materials, due to their partially cross-linked structure, show improved thermal stability, compared to the thermoplastic materials (plastics). The rubber cannot be molten but, at higher temperatures, it undergoes thermal degradation, wherein the temperature of degradation and the degradation rate depend, inter alia, on the crosslinking degree of the rubber material. Thus, during pyrolysis, the heat cannot be evenly distributed within the rubber mass and this leads to a wide large temperature gradients inside the pyrolysis reactor. A system for pyrolysis of the rubber materials should have improved heat and mass transfer properties, as compared to the one that is used for pyrolysis of the plastic (thermoplastic) materials.

[0056] The rubber materials which may be processed by pyrolysis may be of different types: waste rubber such as natural or synthetic rubber comprising polymers, such as for example polyisoprene, polychloroprene, polybutadiene, polyisobutylene, or copolymers such as: poly(styrene-butadiene-styrene). The term “rubber material” is meant to indicate natural rubber (1 ,4-polyisoprene) and synthetic rubbers such as: styrene-butadiene rubbers (SBR), butyl rubbers (consisting of polyisobutylene with addition of diolefin e.g. isoprene) or neoprene (2-chlorobutadiene-1 ,3).

[0057] The rubber materials to be pyrolysed may further comprise different additives, plastificators or fillers. Exemplary rubber materials that may be pyrolysed are worn tires.

[0058] Useful pyrolysis oil may be characterized by their heating value and / or bromine number. The heating value can be assessed in accordance with DIN 51900. Olefin content may be determined with reference to a bromine number. “Bromine number” refers to g of bromine reacting with 100 g of a material, ASTM Method D1159.

[0059] In an embodiment, pyrolysis oil exhibits at least one of the following parameters: a heating value in the range of 35 to 46 kJ / g; a bromine number in the range of 2 to 160 g Br2 / 100g.

[0060] Generally, the cracker feed stream comprises, relative to the total weight of the cracker feed, 0.1 to 45, preferably 42 wt% pyrolysis oil. In another embodiment, the cracker feed stream comprises 1 to 40 wt% pyrolysis oil.

[0061] In another embodiment, the cracker feed stream comprises, relative to the total weight of the cracker feed:

[0062] 0.1 to 20 wt.-% bio-naphtha

[0063] 58 to 99.8 wt.-% fossil-based hydrocarbons; and

[0064] 0.1 to 41.9 wt.-% pyrolysis oil; or 0.1 to 10 wt.-% bio-naphtha,

[0065] 60 to 99.8 wt.-% fossil-based hydrocarbons, and 0.1 to 39.9 wt.% pyrolysis oil; or

[0066] 0.1 to 5 wt.-% bio-naphtha,

[0067] 60 to 99.4 wt.-% fossil-based hydrocarbons, and

[0068] 0.5 to 39.9 wt.% pyrolysis oil.

[0069] In the present process, pyrolysis oil from waste solid organic feedstock including plastics and / or rubber is recycled back as starting materials for high value chemical products, including virgin plastics, to establish a circular economy by combining distinct industrial processes. Benefits accrue if the waste solid organic feedstock has a bio-based carbon content of greater than zero. In this way, high value chemical products with steadily increased bio-based carbon content may be obtained.

[0070] Hence, in an embodiment the pyrolysis oil is obtained from the pyrolysis of a waste solid organic feedstock having a bio-based carbon content of greater than zero, e.g., having a bio-based carbon content of 1 % or more, or 3 % or more. In general, the waste has a bio-based carbon content 10 % or less.

[0071] Steam Cracking

[0072] Steam cracking is a petrochemical process wherein saturated hydrocarbons having long molecular structures are broken down, i.e. cracked, into smaller saturated or unsaturated molecules. Generally, steam crackers aim at producing light alkenes as valuable products, especially ethylene and propylene.

[0073] Conventional steam cracking utilizes a pyrolysis furnace which has two main sections: a convection section and a radiant section. The hydrocarbon feedstock typically enters the convection section of the furnace as a liquid, or, in a case where light feedstocks are used, as a vapor, wherein it is typically heated and, if necessary, vaporized by indirect contact with hot off-gas from the radiant section and by direct contact with steam. The vaporized feedstock and steam mixture is then introduced into the radiant section where the cracking takes place.

[0074] The resulting stream having a temperature typically in the range of from 500 to 650 °C enters a fired tubular reactor and is heated to a temperature typically in the range of from 750 to 875 °C for 0.1 to 0.5 s, wherein the residence time, temperature profile and partial pressure is controlled. During this short reaction time, hydrocarbons in the feedstock are cracked into smaller molecules yielding light olefins such as ethylene, propylene, butylenes, other small olefins, and diolefins as major products besides methane. These reaction products suitably typically leave the radiant tube at a temperature in the range of 800 to 850 °C and are preferably cooled to a temperature typically in the range of from 550 to 650 °C within 0.02 to 0.1 s in order to prevent degradation of the highly reactive compounds by secondary reactions. Then, the resulting reaction products leave the furnace for further downstream processing.

[0075] Processing of the Cracked Gas

[0076] Herein, the designator “Cx” refers to a hydrocarbon including x carbon atoms, “Cx+” refers to a hydrocarbon or mixture of hydrocarbons including x or greater carbon atoms, and “Cxminus” refers to a hydrocarbon of mixture of hydrocarbons including x or fewer carbon atoms.

[0077] Usually, the cracker effluent mixture comprising light olefins such as ethylene, propylene, butylenes, other small olefins, and diolefins besides methane is separated by using a sequence of separation and chemical-treatment steps. The process typically also generates light side products such as hydrogen, carbon oxides, light saturated hydrocarbons, and water.

[0078] The hot cracked gas leaving the cracker is cooled down quickly in order to prevent unwanted follow-up reactions. This is usually done in several steps. In a first step, the cracked gas is cooled down to about 450° C by heat exchangers. A further cooling step occurs via direct contact between the cracked gas and a high boiling liquid, usually referred to as quench oil. The quench results in a partial condensation of the cracked gas. In this step, a heavy stream rich in Ci0+hydrocarbons is separated from the cracked gas. A further cooling step of the cracked gas takes place in a water quench column for primary fractionation, cooling down the gas to around 30 °C. In this step, a C5-9 fraction, commonly referred to as pyrolysis gasoline, is separated from C^inus components.

[0079] The recovery of the various olefin products from cracked gas is usually carried out by fractional distillation using a series of distillation steps or columns to separate out the various components. The unit which separates hydrocarbons with one carbon atom (Ci) and lighter fraction is referred to as “demethanizer”. The unit which separates hydrocarbons with two carbon atoms (C2) from the heavier components is referred to as “deethanizer”. The unit which separates the hydrocarbon fraction with three carbon atoms (C3) from the heavier components is referred to as “depropanizer”. The unit which separates the hydrocarbon fraction with four carbon atoms (C4) from the heavier components is referred to as “debutanizer”.

[0080] The residual heavier components having a higher carbon number fraction (C5+) may be used as gasoline or recycled back to the cracker.

[0081] The various fractionation units may be arranged in a variety of sequences in order to provide desired results based upon various feedstocks. To that end, a sequence which uses the demethanizer first is commonly referred to as the “front-end demethanizer” sequence. Similarly, when the deethanizer is used first, it is commonly referred to as the “front-end deethanizer” sequence. And, when the depropanizer is used first, it is commonly referred to as “front-end depropanizer” sequence.

[0082] In the conventional front-end demethanizer sequence, the cracked gas containing hydrocarbons having one to five or more carbon atoms per molecule (Ci to C5+) first enters a demethanizer, where methane and lighter fractions (hydrogen) are separated as an over-head stream. The demethanizer operates at relatively low temperatures, typically ranging from about -100 °C to about 25 °C.

[0083] The heavy ends exiting the demethanizer consist mainly of C2 to C5+ molecules. These heavy ends then are routed to a deethanizer where the C2hydrocarbons are taken over the top and the C3to C5+compounds leave as bottoms. The C2components leaving the top of the deethanizer may be fed to an acetylene converter or acetylene removal unit. As some methane remains dissolved in the heavy ends exiting the demethanizer and ends up in the C2components leaving the deethanizer, the C2components stream may be subsequently sent to a demethanizer for removal of the remaining methane.

[0084] The C2components from which methane has been removed are then sent to a C2splitter which produces ethylene as the light product and ethane as the heavy product. The C3to C5+stream leaving the bottom of the deethanizer is routed to a depropanizer, which sends the C3components overhead and the C4to C5+components below.

[0085] The C3product may be hydrotreated to remove C3acetylene and dienes before being fed to a C3splitter, where it is separated into propylene at the top and propane at the bottom.

[0086] The C4to C5+stream is fed to a debutanizer, which produces C4components at the top with the balance of C5+components leaving as bottoms. Both the C4and the C5+streams may be separately hydrotreated to remove undesirable acetylenes and dienes.

[0087] In conventional front-end deethanizer sequences, the cracked gas containing Ci to C5+components first enters a deethanizer. The light ends exiting the deethanizer consist of C2and Ci components along with any hydrogen (C2minus fraction). These light ends are fed to a demethanizer (C2minus demethanizer) where the hydrogen and Ci are removed as light ends and the C2components are removed as heavy ends. The C2stream leaving the bottom of the demethanizer may be fed to an acetylene converter and then to a C2splitter which produces ethylene as the light product and ethane as the heavy product. The heavy ends exiting the deethanizer which consist of C3to C5+components are routed to a depropanizer which sends the C3components over-head and the C4to C5+ components below. The C3product is fed to a C3splitter where it is separated into propylene at the top and propane at the bottom, while the C4to C5+ stream is fed to a debutanizer which produces C4compounds at the top with the balance leaving as bottoms to be used for gasoline or to be recirculated as feed into the cracking process. As with the front-end demethanizer sequence, the C3, C4, and C5+streams may be separately hydrotreated to remove undesirable acetylenes and dienes.

[0088] In conventional front-end depropanizer sequences, the quenched and acid-free gases containing hydrocarbons having from one to five or more carbon atoms per molecule (Ci to C5+) first enter a depropanizer. The heavy ends exiting the depropanizer consist of C4to C5+components. These are routed to a debutanizer where the C4components and lighter species are taken over the top with the rest of the feed leaving as bottoms which can be used for gasoline or other chemical recovery. These streams may be separately hydrotreated to remove undesired acetylenes and dienes. The tops of the depropanizer, containing Ci to C3components, may be fed to an acetylene converter and then to a demethanizer system, where the Ci components and any remaining hydrogen are removed as an over-head. The heavy ends exiting the demethanizer system, which contains C2and C3components, are introduced into a deethanizer wherein C2components are taken off the top and C3compounds are taken from the bottom. The C2components are, in turn, fed to a C2splitter which produces ethylene as the light product and ethane as the heavy product. The C3stream is fed to a C3splitter which separates the C3species, sending propylene to the top and propane to the bottom.

[0089] As with the front-end demethanizer sequence, the saturated C2hydrocarbons and / or the saturated C3hydrocarbons obtained in the front-end deethanizer sequence or the frontend depropanizer sequence or a partial stream thereof may be recycled as feed into the cracking process.

[0090] The ethylene recovered from the cracker effluent in this way is provided as the first ethylene stream. In an embodiment, the first ethylene stream is provided with a flow rate (first flow rate) in the range of 10 t / h to 1000 t / h.

[0091] Second Ethylene Stream

[0092] The second ethylene stream is obtained by dehydration of renewably sourced ethanol, namely bioethanol.

[0093] Production of Bioethanol

[0094] In the present invention, bioethanol refers to the ethanol obtained from a biomass feedstock, such as plant or non-crop feedstock containing a carbon source that is convertible to ethanol, for example by microbial metabolism. Typical carbon source examples are starch, sugars like pentoses or hexoses, such as glucose, fructose, sucrose, xylose, arabinose, or degradation products of plants, hydrolysis products of cellulose or juice of sugar canes, beet and the like containing large amounts of the above components. Biomass feedstock can originate from several sources. Bioethanol production may be based on food crop feedstocks such as corn and sugar cane, sugarcane bagasse, cassava (first generation biofeedstock).

[0095] Another source of biomass feedstock is lignocellulosic materials from agricultural crops (second-generation biofeedstock). Potential feedstocks include agricultural residue byproducts such as rice, straw (such as wheat, oat and barley straw), rice husk, and corn stover. Biomass feedstock may also be waste material from the forest products industry (wood waste) and saw dust or produced on purpose as an ethanol crop. Switchgrass and napier grass may be used as on-purpose crops for conversion to ethanol.

[0096] The first-generation bioethanol is produced in four basic steps:

[0097] (1) Enzymatic saccharification or hydrolysis of starch into sugars

[0098] (2) Microbial fermentation of sugars

[0099] (3) Purification by distillation to give hydrous ethanol

[0100] (4) Dehydration (water removal) to produce anhydrous ethanol

[0101] Second-generation feedstocks are considered as renewable and sustainable carbon source. Pretreatment of this feedstock is an essential prerequisite before it is subjected to enzymatic hydrolysis, fermentation, distillation, and dehydration. Pretreatment involves milling and exposure to acid and heat to reduce the size of the plant fibers and hydrolyze a portion of the material to yield fermentable sugars. Saccharification utilizes enzymes to hydrolyze another portion to sugar. Finally, fermentation by bioengineered microorganisms converts the various sugars (pentoses and hexoses) to ethanol. The production of bioethanol is well-known and carried out on an industrial large scale.

[0102] Renewably-sourced ethanol can also be obtained from carbon-containing waste materials like waste products from the chemical industry, garbage and sewage sludge. The production of ethanol from waste materials can be done by gasification to syngas and catalytic conversion thereof the ethanol, see for example Recent Advances in Thermo-Chemical Conversion of Biomass, 2015, Pages 213-250, https: / / doi.org / 10.1016 / B978-0-444-63289-0.00008-9, and Nat Commun 11, 827 (2020), https: / / doi.Org / 10.1038 / S41467-020-14672-8.

[0103] Dehydration of Renewably-Sourced Ethanol

[0104] The production of ethylene by catalytic dehydration of ethanol is a well-known process. The reaction is commonly carried out at 300 to 400 °C and moderate pressure in the presence of a catalyst. Catalytic effects are reviewed in Ind & Eng Chem Research, 52, 28, 9505-9514 (2013), Materials 6, 101-115 (2013) and ACS Omega, 2, 4287-4296 (2017). Examples for catalysts are activated alumina or silica, phosphoric acid impregnated on coke, heteropoly acids (HPA salts), silica-alumina, molecular sieves such as zeoliths of the ZSM-5 type or SAPO-11 type, other zeolites or modified zeolites of various molecular structures with zeoliths and HPA salts being preferred.

[0105] Ethanol dehydration is, for example described in WO 2009 / 098268, WO 2010 / 066830, WO 2009 / 070858 and the prior art discussed therein, WO 2011 / 085223 and the prior art discussed therein, US 4,234,752, US 4,396,789, US 4,529,827 and WO 2004 / 078336.

[0106] The ethanol dehydration reaction is in general carried out in the vapor phase in contact with a heterogeneous catalyst bed using either fixed bed or fluidized bed reactors. For fixed bed reactors, the operation can be either isothermal (with external heating system) or adiabatic (in the presence of a heat carrying fluid). The feedstock is vaporized and heated to the desired reaction temperature; the temperature drops as the reaction proceeds in the reactor. Multiple reactor beds are usually used in series to maintain the temperature drop in each bed to a manageable range. The cooled effluent from each bed is further heated to bring it to the desired inlet temperature of the subsequent beds. Moreover, a portion of the water is recirculated along with fresh and unreacted ethanol. The presence of water helps in moderating the temperature decrease in each bed.

[0107] Prior to dehydration, the renewably-sourced ethanol feedstock may be sent to a pretreatment section to remove mineral contaminants, which would otherwise be detrimental to the downstream catalytic reaction. The pretreatment may involve contacting the renewably-sourced ethanol feedstock with cation and / or anion exchange resins. After a certain period of operation, the resins may be regenerated by passing a regenerant solution through the resin bed(s) to restore their ion exchange capacity. Two sets of beds are preferably operated in parallel to maintain continuous operation. One set of resin beds is suitably regenerated while the other set is being used for pretreatment.

[0108] In the isothermal design, the catalyst is placed inside the tubes of multitubular fixed-bed reactors which arranged vertically and surrounded by a shell (tube and shell design). A heat transfer medium, such as molten salts or oil, is circulated inside the shell to provide the required heat. Baffles may be provided on the shell side to facilitate heat transfer. The cooled heating medium is heated externally and is recirculated. The temperature drop on the process side can be reduced as compared to the adiabatic reactor. A better control on the temperature results in increased selectivity for the ethylene formation and reduction in the amount of undesireable by-products. The temperature is maintained at approximately constant levels within the range of 300° to 350°C. Ethanol conversion is between 98 and 99%, and the selectivity to ethylene is between 94 and 97 mol%. Because of the rate of coke deposition, the catalyst must be regenerated frequently. Depending on the type of catalyst used, the cycle life is between 3 weeks and 4 months, followed by regeneration, for example for 3 days.

[0109] In the adiabatic design, the endothermic heat of reaction is supplied by a preheated inert diluent such as steam. Three fixed-bed reactors may typically be used, with intermediate furnaces to reheat the ethanol / steam mixed feed stream to each reactor. Feeding steam with ethanol results in less coke formation, longer catalyst activity, and higher yields.

[0110] A further process is a fluidized-bed process. The fluidized-bed system offers excellent temperature control in the reactor, thereby minimizing by-product formation. The heat distribution rate of the fluidized bed operation approaches isothermal conditions. The endothermic heat of reaction is supplied by the hot recycled silica-alumina catalyst returning from the catalyst regenerator. Thus, external heating of the reactor is not necessary.

[0111] After dehydration, the reaction mixture is subjected to a separation step. The general separation scheme consists of quickly cooling the reaction gas, for example in a water quench tower, which separates most of the by-product water and the unreacted ethanol from ethylene and other light components which, for example exit from the top of the quench tower. In one type of separation scheme, the water-washed ethylene stream is immediately caustic-washed, for example in a column, to remove traces of CO2. The gaseous stream may enter a compressor directly or pass to a surge gas holder first and then to a gas compressor. After compression, the gas is cooled with refrigeration and then passed through an adsorber with, for example activated carbon, to remove traces of heavy components, (e.g., C4s), if they are present. The adsorber is followed by a desiccant drying and dust filtering step before the ethylene product leaves the plant. This separation scheme produces 99%+ purity ethylene. If desired, the ethylene is further purified by caustic washing and desiccant-drying, and fractionated in a low-temperature column to obtain the final product.

[0112] Several commercial processes are currently in operation, developed by Braskem, Chematur, British Petroleum (BP), and Axens together with Total and IFPEN. The processes differ, e.g., in their process conditions, catalysts and adopted heat integration scheme. The process by BP (now Technip) is called Hummingbird. In this process, a heteropoly acid is used as catalyst, and the reactor operates at 160 to 270 °C and 1 to 45 bar. The unreacted ethanol in recirculated to the reactor. The process developed by Axens is called Atol. Two fixed bed adiabatic reactors, operating at 400 to 500 °C, are used. Chematur’s process operates with four adiabatic tubular reactors. Syndol catalysts, with the main components of AhCh-MgO / SiCh, are employed in this process that was developed by American Halcon Scientific Design, Inc. in the 1980s. In the Braskem process, the adiabatic reactor feed is diluted with steam to a large extent. In such a process, the reactor operates at 180 to 600 °C, preferably 300 to 500 °C, and at 1.9 to 19.6 bar. An alumina or silica-alumina catalyst is used. The Braskem process is described in more detail in US 4,232, 179. A process control in accordance with the Braskem process is particularly preferred.

[0113] In an embodiment, the second ethylene stream is provided with a flow rate (second flow rate) in the range of 10t / h to 1000t / h. Blending of the First and Second Ethylene Stream

[0114] The first and the second ethylene stream are mixed in a ratio as desired for the biobased carbon content in the ethylene-derived chemical(s). The bio-based carbon content in the ethylene-derived chemical(s) can be calculated by the following equation: with

[0115] A: ratio between the second ethylene stream and the first ethylene stream

[0116] Bi : bio-based carbon content of the first ethylene stream

[0117] B2: bio-based carbon content of the second ethylene stream

[0118] C: ratio of the number of carbon atoms originating from ethylene to the total number of carbon atoms in the molecule of an ethylene-derived chemical

[0119] Q: bio-based carbon content in the ethylene-derived chemical(s).

[0120] In an embodiment, the ratio of the first and the second ethylene stream is adjusted, e.g., by adjusting the ratio of the flow rate of the second ethylene stream (second flow) rate to the flow rate of the first ethylene stream (first flow rate), so that Q is 3 % or higher. In an embodiment, Q is 5 % or higher, in particular 10 or higher.

[0121] Chemical Conversion of the Combined Ethylene Stream

[0122] According to the invention, the combined ethylene stream is converted to at least a first generation ethylene-derived chemical selected from

[0123] (a) ethylene oxide,

[0124] (P) ethylbenzene,

[0125] (y) ethylene dichloride; and

[0126] (5) propionaldehyde.

[0127] Optionally, the first generation ethylene-derived chemical is subjected to a chemical conversion or a sequence of chemical conversions to obtain a downstream ethylenederived chemical.

[0128] The first generation ethylene-derived chemical as well as downstream ethylene-derived chemicals have a defined a bio-based carbon content.

[0129] The chemical conversion or a sequence of chemical conversions may include (a) reaction(s) with (a) carbon-containing reagent(s) with the consequence that the carbon atoms constituting the molecule of the first generation ethylene-derived chemical and / or the downstream ethylene-derived chemical are of mixed origin. In preferred embodiments, the first generation ethylene-derived chemical and / or the downstream ethylene-derived chemical has / have a ratio of the number of carbon atoms originating from the combined ethylene stream to the total number of carbon atoms in the molecule of > 0.25.

[0130] Ethylene Oxide

[0131] In an embodiment, the first generation ethylene-derived chemical is ethylene oxide. Thus, in one embodiment step d) comprises an epoxidation reaction of the combined ethylene stream to produce ethylene oxide having a bio-based carbon content.

[0132] Ethylene oxide is produced in large volumes and is primarily used as an intermediate in the production of several industrial chemicals. Suitable epoxidation catalysts are generally obtained by depositing metallic silver on a support. Highly selective silverbased epoxidation catalysts have been developed, which comprise, in addition to silver as the active component, promoting species for improving the catalytic properties of the catalyst, as described in, e.g., WO 2007 / 122090 A2 and WO 2010 / 123856 A1. Examples of promoting species include alkali metal compounds and / or alkaline earth metal compounds, as well as transition metals such as rhenium, tungsten or molybdenum.

[0133] Suitable catalysts typically comprise 20 to 35 % or 25 to 45 wt.-% of silver, relative to the weight of the catalyst.

[0134] As support material, it is possible to use various porous refractory materials such as activated carbon, titania, zirconia, silica, alumina or ceramic compositions or mixtures of these materials. Preferably, the refractory support is an aluminum oxide support. The supports preferably has a BET surface area of 0.5 to 3.0 m2 / g.

[0135] A suitable catalyst may be obtained by i) impregnating a refractory support with a silver impregnation solution, preferably under reduced pressure; and optionally subjecting the impregnated refractory support to drying; and ii) subjecting the impregnated refractory support to a calcination process; wherein steps i) and ii) are optionally repeated.

[0136] The epoxidation of ethylene preferably comprises reacting ethylene and oxygen in the presence of an epoxidation catalyst as described above. The epoxidation can be carried out by all processes known to those skilled in the art. It is possible to use all reactors which can be used in the ethylene oxide production processes of the prior art; for example externally cooled shell-and-tube reactors (cf. Ullmann's Encyclopedia of Industrial Chemistry, 5th edition, vol. A-10, pp. 117-135, 123-125, VCH- Verlagsgesellschaft, Weinheim 1987) or reactors having a loose catalyst bed and cooling tubes, for example the reactors described in DE 34 14 717 A1, EP 0 082 609 A1 and EP 0 339 748 A2. The epoxidation is preferably carried out in at least one tube reactor, preferably in a shell - and-tube reactor. On a commercial scale, ethylene epoxidation is preferably carried out in a multi-tube reactor that contains several thousand tubes. The catalyst is filled into the tubes, which are placed in a shell that is filled with a coolant. In commercial applications, the internal tube diameter is typically in the range of 20 to 40 mm (see, e.g., US 4,921 ,681 A) or more than 40 mm (see, e.g., WO 2006 / 102189 A1).

[0137] To prepare ethylene oxide from ethylene and oxygen, it is possible to carry out the reaction under conventional reaction conditions as described, e.g., in DE 25 21 906 A, EP 0 014457 A2, DE 23 00 512 A1, EP 0 172 565 A2, DE 24 54 972 A1, EP 0 357 293 A1 , EP 0 266 015 A1 , EP 0 085 237 A1, EP 0 082 609 A 1 and EP 0 339 748 A2. Inert gases such as nitrogen or gases which are inert under the reaction conditions, e.g. steam, methane, and also optionally reaction moderators, for example halogenated hydrocarbons such as ethyl chloride, vinyl chloride or 1,2-dichloroethane can additionally be mixed into the reaction gas comprising ethylene and molecular oxygen.

[0138] The reaction gas preferably comprises a chlorine-comprising reaction moderator such as ethyl chloride, vinyl chloride or 1,2-dichloroethane in an amount of from 0 to 15 ppm by weight, preferably in an amount of from 0.1 to 8 ppm by weight, based on the total weight of the reaction gas. The remainder of the reaction gas generally comprises hydrocarbons such as methane and also inert gases such as nitrogen. In addition, other materials such as steam, carbon dioxide or noble gases can also be comprised in the reaction gas.

[0139] The concentration of carbon dioxide in the feed (i.e. the gas mixture fed to the reactor) typically depends on the catalyst selectivity and the efficiency of the carbon dioxide removal equipment. Carbon dioxide concentration in the feed is preferably at most 3 vol.-%, more preferably less than 2 vol.-%, most preferably less than 1 vol.-%, relative to the total volume of the feed. An example of carbon dioxide removal equipment is provided in US 6,452,027 B1.

[0140] The epoxidation of ethylene to ethylene oxide is usually carried out at elevated catalyst temperatures. Preference is given to catalyst temperatures in the range of 150 to 350 °C, more preferably 180 to 300 °C, particularly preferably 190 to 280 °C and especially preferably 200 to 280 °C.

[0141] The epoxidation is preferably carried out at pressures in the range of 5 to 30 bar. All pressures herein are absolute pressures, unless noted otherwise. The epoxidation is more preferably carried out at a pressure in the range of 5 to 25 bar, such as 10 bar to 24 bar and in particular 14 bar to 23 bar.

[0142] The epoxidation of ethylene is preferably carried out under conditions conducive to obtain a reaction mixture containing at least 2.3 vol. % of ethylene oxide. In other words, the ethylene oxide outlet concentration (ethylene oxide concentration at the reactor outlet) is preferably at least 2.3 vol. %. The ethylene oxide outlet concentration is more preferably in the range of 2.5 to 4.0 vol. %, most preferably in the range of 2.7 to 3.5 vol. %.

[0143] The epoxidation is preferably carried out in a continuous process. The epoxidation of ethylene can advantageously be carried out in a recycle process. After each pass, the newly formed ethylene oxide and the by-products formed in the reaction are removed from the product gas stream. The remaining gas stream is supplemented with the required amounts of ethylene, oxygen and reaction moderators and reintroduced into the reactor. The separation of the ethylene oxide from the product gas stream and its workup can be carried out by customary methods of the prior art (cf. Ullmann's Encyclopedia of Industrial Chemistry, 5th edition, vol. A-10, pp. 117-135, 123-125, VCH- Verlagsgesellschaft, Weinheim 1987).

[0144] The epoxidation of ethylene proceeds with less than 100% selectivity and is accompanied by the generation of carbon dioxide. It should be appreciated that emission of the carbon dioxide side product does not contribute to the carbon footprint of this process, as the starting ethylene is carbon neutral.

[0145] Hydrolysis Reaction of Ethylene Oxide

[0146] In an embodiment, the downstream ethylene-derived chemical is selected from ethylene glycol, polyethylene glycol, and ethylene glycol ethers.

[0147] In one embodiment, step e) comprises a hydrolysis reaction of the ethylene oxide to produce ethylene glycol and / or ethylene glycol ethers. The ethylene glycol and the ethylene glycol ethers may be used in a large variety of industrial applications, for example in the fields of food, beverages, tobacco, cosmetics, thermoplastic polymers, curable resin systems, detergents and heat transfer systems.

[0148] The hydrolysis reaction of the ethylene oxide as such is known and typically comprises reacting the ethylene oxide with water, suitably using an acidic or a basic catalyst. For example, for obtaining predominantly ethylene glycol (1 ,2-ethanediol) and less ethylene glycol ethers, the ethylene oxide may be reacted with a ten fold molar excess of water, in a liquid phase reaction in presence of an acid catalyst, e.g., 0.5 to 1.0 wt.-% sulfuric acid, based on the total reaction mixture, at 50 to 70 °C and at 1 bar absolute, or in a gas phase reaction at 130 to 240 °C and 20 to 40 bar absolute, preferably in the absence of a catalyst.

[0149] If the proportion of water is lowered, the proportion of ethylene glycol ethers in the reaction mixture is increased. The ethylene glycol ethers thus produced may be a diether, tri-ether, tetra-ether or a subsequent ether. Alternative ethylene glycol ethers may be prepared by converting the ethylene oxide with an alcohol, in particular a primary alcohol, such as methanol or ethanol, by replacing at least a portion of the water by the alcohol. Higher ethylene glycol ethers (polyethylene glycols) are prepared by anionic polymerization of ethylene oxide. For mole masses up to about 40.000 g / mole bases such as sodium ethanolate or potassium tert-butanolate are used for initiation. Polyethylene glycols having mole masses up to 3.000.000 g / mole are obtained with basic catalysts such as alkaline earth oxides or carbonates.

[0150] Amination Reaction of Ethylene Oxide

[0151] In another embodiment, step e) comprises an amination reaction of the ethylene oxide to produce ethanolamines and / or ethylene amines as downstream ethylene-derived chemicals. Ethanolamine may be used, e.g., in the treating (“sweetening”) of natural gas. Ethylene amines are used as solvents, stabilizers, starting materials for the synthesis of chelating agents, fungicides, micronutrients, synthetic resins, fibres, medicaments, inhibitors, and interface-active substances.

[0152] The amination of ethylene oxide in a first step provides ethanolamines, such as monoethanol amine and diethanol amine, which in a subsequent step may be aminated to give the desired ethylene amine. These reactions take place at a high pressure and a high temperature and lead to the formation of a number of side products as well.

[0153] To obtain ethanolamines, the amination reaction typically comprises reacting the ethylene oxide with ammonia, alkylamines such as monoalkylamines and dialkylamines, alkanolamines, or aromatic amines, preferred is ammonia. Anhydrous or aqueous ammonia may be used, although anhydrous ammonia is typically used to favor the production of monoethanolamine. For methods applicable in the conversion of the ethylene oxide into the ethanolamine, reference may be made to, for example US 4,845,296. The obtained ethanolamine preferably is monethanolamine or diethanolamine or a mixture of these two. Most preferably, the ethanolamine is monoethanolamine.

[0154] Amination of ethylene oxide with ammonia yields a stream comprising ammonia, monoethanolamine, diethanolamine and triethanolamine. Ethanolamines may be separated from this stream. Alternatively, the stream may be fed at least partially to a subsequent amination reaction with, e.g., ammonia, to obtain ethylene amines, such as ethylenediamine.

[0155] Suitable catalysts may contain a catalytically active compound on a solid support. Usually the catalyst contains as the catalytically active part at least one metal selected from the group consisting of nickel, chromium, cobalt, copper, ruthenium, iron, calcium, magnesium, strontium, lithium, sodium, potassium, barium, cesium, tungsten, silver, zinc, uranium, titanium, rhodium, palladium, platinum, iridium, osmium, gold, molybdenum, rhenium, cadmium, lead, rubidium, boron, and manganese, or mixtures thereof. The temperature used during amination is generally between 120 and 300 °C, preferably in the range between 175 and 225 °C. The pressure used during amination is generally in the range of 8 to 40 MPa, preferably 15 to 30 MPa.

[0156] Alkylation of Benzene with Ethylene

[0157] In another embodiment, the first generation ethylene-derived chemical is ethylbenzene. Thus, in an embodiment, step d) of the invention comprises reacting the combined ethylene stream with benzene in an alkylation reaction to produce ethylbenzene.

[0158] Benzene can be alkylated with ethane preferably in liquid phase to produce ethylbenzene. In general, the alkylation is carried out at a temperature of 80 to 130 °C and in the presence of a Lewis acid catalyst such as AICI3, AIBr3, FeCI3, ZrCI4, and BF3 with AICI3 being preferred. Ethyl chloride or hydrogen chloride may be used as a catalyst promoter. Further details can be taken from Ullmann’s Encyclopedia of Industrial Chemistry, 5th ed., vol. A10, 35-40, 1987.

[0159] Dehydrogenation of Ethylbenzene to Styrene and Polymerization

[0160] In another embodiment, the ethylbenzene is subjected to a dehydrogenation reaction to produce styrene as a downstream ethylene-derived chemical. To produce styrene the obtained ethylbenzene is dehydrogenated in the vapor phase with steam over a catalyst comprising iron oxide. The dehydrogenation can be carried out adiabatically or isothermally. Further details can be taken from Ullmann’s Encyclopedia of Industrial Chemistry, 6th ed., vol. 34, 386-390, 2003.

[0161] The obtained styrene can be polymerized to polystyrene or polystyrene copolymers, such as styrene-butadiene copolymers in a conventional manner.

[0162] Dichloroethane, Vinylchloride and Polymerization

[0163] In another embodiment, step d) comprises conversion of the combined ethylene stream to ethylene dichloride (1,2-dichloroethane) as the first generation ethylene-derived chemical. Production of 1 ,2-dichloroethane is primarily achieved through the iron(lll) chloride-catalysed reaction of ethylene and chlorine. It is also generated by the copper(ll) chloride-catalysed oxychlori nation of ethylene.

[0164] A known process for oxychlorination of ethylene to produce 1,2-dichloroethane involves reaction of a mixture of ethylene, hydrogen chloride and oxygen or an oxygen containing gas, e.g. , air, in the vapor phase over a fixed catalyst bed or a fluidized catalyst bed. The conditions are generally described in U.S. Pat. No. 3,488,398. The typical catalyst used in oxychlorination reactions comprises a copper compound, preferably copper chloride, as the active catalytic ingredient, uniformly deposited on a support body or fine particles of a fluidizable support. The support is preferably alumina. 1 ,2-Dichloroethane is primarily used for the industrial production of vinyl chloride by dehydrochlorination via thermal cracking under elimination of hydrogen chloride. For details of the cracking procedure reference is made to Ullmann’s Encyclopedia of Industrial Chemistry, 6th ed., vol. 8, 59-62. Industrially, vinyl chloride is used essentially exclusively for the industrial polymerization to poly(vinyl chloride). A variety of polymerization methods for obtaining poly(vinylchloride) is known. For details of the polymerization method reference is made to Ullmann’s Encyclopedia of Industrial Chemistry, 6th ed., vol. 29, 1-29.

[0165] Hydroformylation of Ethylene

[0166] In another embodiment, step d) comprises converting the combined ethylene stream to propionaldehyde as the first generation ethylene-derived chemical. In one embodiment, ethylene is subjected to hydroformylation to produce propionaldehyde.

[0167] Hydroformylation or the oxo process is an important large-scale industrial process for preparing aldehydes from olefins, carbon monoxide and hydrogen. These aldehydes can optionally be hydrogenated with hydrogen in the same operation or subsequently in a separate hydrogenation step, to produce the corresponding alcohols. In general, hydroformylation is carried out in the presence of catalysts which are homogeneously dissolved in the reaction medium. Catalysts used are generally the carbonyl complexes of metals of transition group VIII, in particular Co, Rh, Ir, Pd, Pt or Ru, which may be unmodified or modified with, for example, amine-containing or phosphine-containing ligands. A summarizing account of the processes practiced on a large scale in industry is found in J. Falbe, “New Syntheses with Carbon Monoxide”, Springer Verlag 1980, p. 162 ff_, US 3,527,809; 3,917,661 ; 4, 148,830; 4,742, 178, 4,769,984; 4,885,401 ; 6,049,011.

[0168] Ethylene is preferably hydroformylated using ligand-modified rhodium carbonyls as the catalyst. Hydroformylation of ethylene can be carried out at temperatures in the range of 50 °C to 200 °C, preferably 60 °C to 150 °C, and more preferably 70 °C to 120 °C.

[0169] In one embodiment, the hydroformylation reaction is conducted at a low pressure, e.g., a pressure in the range of 0.05 to 50 MPa (absolute), and preferably in the range of about 0.1 MPa to 30 MPa, most preferably at a pressure below 5 MPa. Desirably, the partial pressure of carbon monoxide is not greater than 50% of the total pressure.

[0170] The proportions of carbon monoxide, hydrogen, and ethylene in the hydroformylation reaction medium can be selected within a wide range. In some embodiments, based on the total amount of CO, hydrogen, and ethylene, CO is from about 1 to 50 mol-%, preferably about 1 to 35 mol-%; H2is from about 1 to 98 mol-%, preferably about 10 to 90 mol-%; and ethylene is from about 0.1 to 35 mol-%, preferably about 1 to 35 mol-%. The hydroformylation reaction preferably takes place in the presence of both liquid and gas phases. The reactants generally are in the gas phase. The catalyst typically is in the liquid phase. Because the reactants are gaseous compounds, a high contact surface area between the gas and liquid phases is desirable to enhance good mass transfer. A high contact surface area between the catalyst solution and the gas phase may be provided in any suitable manner. In a batch process, the batch contents are thoroughly mixed during the course of the reaction. In a continuous operation the reactor feed gas can be contacted with the catalyst solution in, for example, a continuous-flow stirred autoclave where the gas is introduced and dispersed at the bottom of the vessel, preferably through a perforated inlet (e.g., a sparger). High contact between the catalyst and the gas feed may also be provided by dispersing the solution of the Rh catalyst on a high surface area support, a technique well known in the art as supported liquid phase catalysis, or providing the Rh as part of a permeable gel.

[0171] The reaction may be conducted either in a batch mode or, preferably, on a continuous basis. One or more reactors may be used in continuous modes to carry out the reaction in one or more stages.

[0172] The ratio of H2to CO in the syngas used for hydroformylation is desirably in the range from 1.1 :1 to 1.01 : 1, preferably 1.06: 1 to 1.02: 1. Often, syngas may be made or otherwise initially provided in a manner such that the ratio of hydrogen to CO is much higher than this. The excess hydrogen can be separated and used in other reaction stages as desired. For example, the excess hydrogen may be used to reduce propionaldehyde to propanol. In some modes of practice, syngas in the practice of the present invention is anhydrous.

[0173] Conversion of Propionaldehyde to Downstream Ethylene-Derived Chemicals

[0174] In one embodiment, step e) comprises subjecting propionaldehyde to hydrogenation to produce n-propanol as downstream ethylene-derived chemical.

[0175] Propionaldehyde can optionally be reacted with hydrogen in the hydroformylation reaction step, or subsequently in a separate hydrogenation step, to produce n-propanol. This hydrogenation is a well-known reaction and can be conducted by any suitable known process.

[0176] In one embodiment, the hydrogenation is carried out with hydrogen in the liquid or gas phase in the presence of a hydrogenation catalyst. Homogeneous or heterogeneous catalysts can be used. Copper catalysts have proved to be the most suitable. Typically, the reaction is carried out in the liquid phase on fixed-bed catalysts at 20 to 200 °C and pressures of up to 30 MPa. Hydrogenation in the gas phase is preferably carried out continuously. Further details can be taken from Ullmann’s Encyclopedia of Industrial Chemistry, 2018, Chapter Propanal, DOI: 10.1002 / 14356007. a22_157. pub3. In another embodiment, step e) comprises subjecting propionaldehyde to oxidation to produce propionic acid as downstream ethylene-derived chemical. The oxidation can be carried out in accordance with any known method. In an embodiment, the oxidation is carried out by catalytic liquid phase oxidation using atmospheric oxygen. The reaction is carried out at a temperature of 30-100 °C and 1-3 bar using manganese(ll) propionate as catalyst and propionic acid as solvent. Further details are given in Technische Organische Chemie - Grundstoffe, Zwischenprodukte, Finalprodukte, Polymere. 1. Auflage. Deutscher Verlag fur Grundstoffindustrie, Leipzig 1992, page 133.

[0177] In another embodiment, step e) comprises conversion of propionaldehyde to trimethylolethane as a downstream ethylene-derived chemical. Trimethylolethane is made by condensation of propionaldehyde with an excess of formaldehyde (US2790837; WO2012110436). Trimethylolethane is a versatile component for polyester resins.

[0178] Environmental Attribute Data

[0179] The products manufactured based on the process according to the present invention may be associated with one or more environmental attribute(s). Environmental attribute(s) refer to any property or characteristic related to the environmental impact of a chemical. The environmental attribute may indicate an environmental performance of a starting material or the manufacturing process. The environmental attribute may relate to a product carbon footprint (PCF). The environmental attribute may also relate to a renewable, a bio-based and / or a recycled content, e.g. of an input material and / or a chemical product.

[0180] The association of an environmental attribute to a respective product follows specific rules and regulations. For instance, bio content and recycle content attributes may be handed in accordance with respective standards (e.g. ISCC PLUS or REDcert2). In principle one can distinguish two kinds of so-called balancing approaches a material and a mass balance content. A material content for instances specifies the actual content of bio-based carbons in a product. It needs to be verifiable (e.g. by C14 analysis or using bil l-of-material). How to determine a biocarbon content via bill of material is for instance taught in DIN EN 16785-2.

[0181] A mass balance approach (as for instance provided by ISCC PLUS or REDcert2) can be applied to bio as well a recycle contents. The term “mass balance” refers to a process by which inputs and outputs, and associated information, are transferred, monitored, and controlled as they move through the relevant supply chain. Such a process is called a chain of custody model. The increasing focus on converting to sustainable renewable or recycled feedstocks, make it increasingly important for companies to be able to follow and control the chain of custody that they are directly active in, but also to be able to transparently communicate and credibly verify it. A verified chain of custody can, for instance, show the origin and sustainability of feedstocks used, the different conversion and transportation steps in the chain, and the efficiency of these steps. The handling of environmental attributes is complex and requires digital solutions. For example, the respective environmental attributes associated with input material (in particular the bio content of bio-ethanol or the bio- or recycle content of a pyrolysis oil, bio-naphtha or syngas) can be allocated to a, preferably digital, balancing account associated with the respective environmental attribute. From such balancing account they can be assigned to one or more products manufactured in accordance with the present invention.

[0182] Any respective product manufactured in accordance with the present invention can be further associated with a digital identifier. Such digital identifier may be based on decentral identifiers and / or block chain technology. A digital identifier is particularly designed to monitor and control environmental attributes through the entire value chain including, where applicable, subsequent recycling. Such identifiers may (digitally) persist while the respective chemical product to which they are associated is further processed. In general, they help to verify a chain of custody.

[0183] Respective digital methods designed to handle environmental attributes are described in more detail in WO 2023 / 117903 A1 , WO 2023 / 117897, WO 2023 / 117950 A1, WO 2023 / 117972 A1 , and WO 2023 / 112013 A1 (all BASF SE), all of which are herewith incorporated by reference.

[0184] It is also possible to combine a chemical product manufactured in accordance with the present invention with one or more environmental attributes and a determined (e.g. measured via C14 or calculated via bill of material) biocarbon content value. Respective digital methods are described in more detail in EP application 23171760.4, which is herewith incorporated by reference.

Claims

Claims1. A process for the manufacture of one or more ethylene-derived chemical(s) having a bio-based carbon content, the process comprising the steps of:(a) providing a first ethylene stream by(a-i) providing a cracker feed stream containing bio-naphtha and fossil-based hydrocarbons,(a-ii) subjecting the cracker feed to steam cracking to obtain a cracker effluent,(a-iii) recovering from the cracker effluent the first ethylene stream;(b) providing a second ethylene stream having a bio-based carbon content by subjecting a feedstock comprising bioethanol to dehydration;(c) combining the first ethylene stream and the second ethylene stream to obtain a combined ethylene stream;(d) converting the combined ethylene stream to at least a first generation ethylene-derived chemical selected from(a) ethylene oxide,(P) ethylbenzene,(y) ethylene dichloride; and(5) propionaldehyde; and(e) optionally subjecting the first generation ethylene-derived chemical to a chemical conversion or a sequence of chemical conversions to obtain a downstream ethylene-derived chemical.

2. The process according to claim 1, wherein the first generation ethylene-derived chemical is ethylene oxide and a downstream ethylene-derived chemical is selected from ethylene glycol, polyethylene glycol, ethylene glycol ethers, and ethanolamines; the first generation ethylene-derived chemical is ethylbenzene, and the downstream ethylene-derived chemical is styrene; the first generation ethylene-derived chemical is ethylene dichloride, and the downstream ethylene-derived chemical is vinyl chloride; or the first generation ethylene-derived chemical is propionaldehyde, and the downstream ethylene-derived chemical is selected from propanol, propionic acid and trimethylolethane.

3. The process according to claim 2, wherein the downstream ethylene-derived chemical is selected from ethanolamines, step (e) further comprising conversion of the ethanolamine(s) to an ethylene amine; the downstream ethylene-derived chemical is styrene, step (e) further comprising conversion of the styrene to polystyrene; or the downstream ethylene-derived chemical is vinyl chloride, step (e) further comprising conversion of the vinyl chloride to polyvinylchloride.

4. The process according to any of the preceding claims, wherein the cracker feed stream comprises, relative to the total weight of the cracker feed:0.1 to 20 wt.% bio-naphtha; and80 to 99.9 wt.-% fossil-based hydrocarbons; preferably0.1 to 10 wt.% bio-naphtha; and90 to 99.9 wt.-% fossil-based hydrocarbons.

5. The process according to any one of claims 1 to 3, wherein the cracker feed stream additionally comprises pyrolysis oil.

6. The process according to claim 5, wherein the cracker feed stream comprises, relative to the total weight of the cracker feed, 0.1 to 45 wt.-% pyrolysis oil.

7. The process according to claim 6, wherein the cracker feed stream comprises, relative to the total weight of the cracker feed:0.1 to 20 wt.-% bio-naphtha58 to 99.8 wt.-% fossil-based hydrocarbons;0.1 to 41.9 wt.-% pyrolysis oil; or0.1 to 10 wt.-% bio-naphtha,60 to 99.8 wt.-% fossil-based hydrocarbons, and0.1 to 39.9 wt.% pyrolysis oil; or0.1 to 5 wt.-% bio-naphtha,60 to 99.4 wt.-% fossil-based hydrocarbons, and0.5 to 39.9 wt.% pyrolysis oil.

8. The process according to any of claims 5 to 7, wherein the pyrolysis oil is obtained from the pyrolysis of a waste comprising at least one material having a bio-based carbon content greater than zero.

9. The process according to claim 8, wherein the at least one material is selected from a plastic and a rubber.

10. The process according to any of claims 5 to 9, wherein the pyrolysis oil exhibits at least one of the following parameters:- a heating value in the range of 35 to 46 kJ / g; and- a bromine number in the range of 2 to 160 g Br2 / 100g.

11. The process according to any of the preceding claims, wherein the bio-naphtha is at least partially obtained from the hydrogenation of fatty acids, fatty acid derivatives, mono-, di- or, triglycerides, or a combination thereof.

12. The process according to any of the preceding claims, wherein the second ethylene stream has a bio-based carbon content in the range of 50 to 100%.

13. The process according to any of the preceding claims, wherein the downstream ethylene-derived chemical(s) has / have a ratio of the number of carbon atoms originating from the combined ethylene stream to the total number of carbon atoms in the molecule of > 0.25.

14. The process according to any of the preceding claims, wherein the weight ratio of the first ethylene stream to the second ethylene stream is chosen such that the bio-based carbon content of the one or more ethylene-derived chemical(s) is at least 3%.

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