Method for producing isononanol from ethanol of renewable source

Abstract

A process for the manufacture of isononanol, the process comprising subjecting a feedstock comprising ethanol of a renewable source to dehydration to produce an ethylene stream of a renewable source. The renewable source ethylene stream is subjected to olefin mutual conversion to obtain a renewable source C4-olefin stream comprising n-butene, isobutene, or a mixture of n-butene and isobutene. The interconversion of olefins comprises (i) and, if desired, (ii), or (ii) and (iii): (i) dimerization of ethylene to obtain n-butenes; (ii) isomerizing the n-butenes obtained according to (i) to obtain isobutene; (iii) blending the n-butene obtained according to (i) with the isobutene obtained according to (ii). Subjecting the C4-olefin stream of renewable origin to a series of chemical conversions to obtain isononanol, comprising: oligomerizing the C4-olefin stream of renewable origin to produce dibutene; subjecting these dibutenes to a hydroformylation reaction with synthesis gas to obtain isononanal; and hydrogenating the isononyl aldehyde to produce isononyl alcohol. The method provides a reaction scheme for isononyl alcohol of renewable sources.

Description

BACKGROUND OF THE INVENTION

[0001] The present invention relates to a process for manufacturing isononanol from ethanol of renewable origin.

[0002] Isononanol (INA) is an example of an oxo alcohol with a high global demand. INA is used essentially for the production of plasticizers. 'Green' products from natural or renewable sources have become a trend.

[0003] Ethylene is the cornerstone of the modern petrochemical industry. Important ethylene derivatives (at the ends of their respective chains) include (meth)acrylic acid, (meth)acrylates, isononanol, 2-ethylhexanol, and ethylene glycol. One of the problems faced in manufacturing chemicals and intermediates from ethylene is that the starting materials are derived from fossil fuels such as natural gas or crude oil, which are non-renewable raw materials. Steam cracking using petroleum fractions and natural gas liquids as raw materials is the dominant method for large-scale production of ethylene globally.

[0004] Lower olefins, such as isobutene or propylene, are of great importance for industrial and chemical applications. Isobutylene, also known as isobutene or 2-methylpropene, is a hydrocarbon of great significance, which is widely used as an intermediate in the production of industrially important products, including p-xylene, jet fuel mixtures, gasoline oxygenates, isooctane, methacrolein, methyl methacrylate, and butyl rubber. Propylene is a hydrocarbon of great significance that is widely used as an intermediate in the production of acrylic acid. Historically, lower olefins have been obtained by catalytic or steam cracking of fossil fuel raw materials.

[0005] The Applicants have recognized that the production of ethylene and ethylene derivative compounds would benefit from replacing at least a portion of the carbonaceous feedstock of fossil origin with renewable resources such as carbonaceous materials derived from biomass. Ethanol feedstock produced from renewable resources is of particular interest. This ethanol from renewable sources (also known as "bioethanol" or "hydrous fuel alcohol") can be prepared in large quantities from organic waste or biomass via fermentation. Different raw materials for producing ethanol can be sucrose-containing raw materials such as sugarcane, starch materials such as corn, starch, wheat, cassava, lignocellulosic biomass such as switchgrass, and / or agricultural waste. The purification or separation of bioethanol is often carried out by complex multi-stage distillation.

[0006] Even after the purification process, the advantages of bioethanol are often reduced due to the small amount of impurities it contains. Bioethanol impurities can include oxygenated organic compounds such as other alcohols like isopropanol, n-propanol, and isobutanol, and / or aldehydes such as acetaldehyde. Bioethanol impurities can further include sulfur-containing impurities such as inorganic sulfur compounds dialkyl sulfides, dialkyl sulfoxides, alkyl mercaptans, 3-methylthio-1-propanol, and / or sulfur-containing amino acids.

[0007] There is a desire to integrate ethanol from renewable sources into existing processes designed to convert fossil-derived ethylene or its intermediates. However, some impurities may interfere with the downstream processes of using bioethanol as a feedstock and producing chemical products, especially when some of the downstream steps are catalytic conversions.

[0008] If no effort is made to remove at least some of these impurities, the yields of the desired intermediates and final products, as well as the efficacy of the overall process, may be reduced.

[0009] US2008 / 0312485 discloses a process for the continuous production of propylene by dehydrating ethanol obtained from biomass to obtain ethylene and reacting the ethylene with 1-butene in a metathesis reaction. The 1-butene is prepared by dimerization of ethylene, which is obtained from biomass-derived ethanol

[0033] and

[0061] .

[0010] WO 2010 / 066830 discloses the conversion of bioethanol to ethylene. The bioethanol is produced by fermentation of carbohydrates or from syngas made by gasification of biomass. Subsequently, the ethylene is dimerized or oligomerized to, for example, 1-butene and / or 1-hexene. The dimerized or oligomerized α-olefins are converted to internal olefins, which are then subjected to metathesis with ethylene.

[0011] WO 2011 / 085223 discloses an integrated process for preparing renewable hydrocarbons. The process includes dehydrating renewable isobutanol to form a mixture of linear butenes and isobutene, and dehydrating renewable ethanol to ethylene. Subsequently, the butene mixture and ethylene are reacted to form one or more renewable C 3 -C 16 olefins.

[0012] EP 3 067 340 A discloses a process that includes fermenting a renewable carbon source to produce a mixture of alcohols comprising ethanol, isopropanol, and 1-butanol; co-dehydrating the alcohols to produce a mixture of olefins that mainly comprises ethylene, propylene, and linear butenes in addition to water and by-products, the linear butenes being a mixture of 1-butene and 2-butene (cis- and trans-isomers); removing water, oxygenates, and other by-products from the mixture of olefins to produce a mixture of olefins that mainly comprises ethylene, propylene, and linear butenes; and passing the mixture of olefins through an isomerization bed such that 1-butene is isomerized to 2-butene, and subsequently passing the mixture of olefins that mainly comprises ethylene, propylene, and 2-butene through a metathesis bed to effect the reaction between ethylene and 2-butene to produce additional propylene.

[0013] WO 2009 / 098268 discloses a process for dehydrating an alcohol to produce an olefin. The alcohol can be ethanol obtainable from carbohydrates. For this purpose, a stream comprising ethanol and an inert component is contacted with a catalyst to obtain ethylene. It is shown that ethylene can be dimerized to butene and then isomerized to isobutene, dimerized to 1-butene, isomerized to 2-butene and further converted to propylene by metathesis with ethylene, or converted to ethylene oxide and ethylene glycol. Only experimental details of ethanol dehydration are provided. A similar process is disclosed in WO 2011 / 089235.

[0014] WO 2009 / 098269 discloses a process for converting ethanol to propylene, the ethanol being obtainable from carbohydrates. The ethanol is dehydrated to ethylene which reacts with an olefin having four or more carbon atoms to obtain propylene. A similar process is disclosed in WO2009 / 098267.

[0015] WO 2021 / 067294 discloses a process for simultaneously dehydrating, dimerizing and metathesizing C 2 -C 5 alcohols to produce C 2 -C 7 olefins in one reactor.

[0016] WO 2009 / 070858 discloses an integrated process for producing an ethylene-butene copolymer. The ethylene is obtained by dehydration of ethanol which is produced by fermentation of sugars. One method for obtaining 1-butene for polymerization is indicated to be by dimerization of ethylene produced by dehydration of ethanol which is produced by fermentation of sugars. No details of the dimerization are given.

[0017] In an embodiment, the present invention seeks to propose a reaction scheme which provides light olefins from renewable sources, such as ethylene, butene and isobutene, which light olefins partially or fully replace the light olefins output from a steam cracker. These light olefins are used as building blocks for producing a variety of chemicals of interest. Desirably, the light olefins from renewable sources can be blended with or used interchangeably with fossil-derived intermediates having the same chemical structure without adjustment in downstream processes. This includes that the starting olefins (which have historically been provided by the output of a steam cracker) for all branches of the value chain can be supplied on a renewable basis simultaneously. In this way, at least the greenhouse gas footprint and / or the carbon footprint for producing the chemicals of interest is reduced. Detailed Description

[0018] To this end, the present invention relates to a process for manufacturing isononanol, said process comprising the following steps:

[0019] a) Subject a feedstock comprising ethanol from renewable sources to dehydration to produce an ethylene stream from renewable sources;

[0020] b) Subject the ethylene stream from renewable sources to olefin metathesis to obtain a C 4 - olefin stream from renewable sources, the C 4 - olefin stream from renewable sources comprising 1-butene, isobutene or a mixture of 1-butene and isobutene; the olefin metathesis comprises (i) and, if desired, (ii), or (ii) and (iii):

[0021] (i) Dimerize ethylene to obtain 1-butene;

[0022] (ii) Isomerize the 1-butene obtained according to (i) to obtain isobutene;

[0023] (iii) Blend the 1-butene obtained according to (i) with the isobutene obtained according to (ii); and

[0024] c) Subject the C 4 - olefin stream from renewable sources to a series of chemical conversions to obtain isononanol, including:

[0025] α) Oligomerize the C 4 - olefin stream from renewable sources to produce dibutenes;

[0026] β) Subject these dibutenes to a hydroformylation reaction with syngas to obtain isononanal; and

[0027] γ) Hydrogenate the isononanal to produce isononanol.

[0028] The term "isononanol" should be understood to refer to isomeric nonanols such as n-nonanol and mixtures of mono-branched and / or multi-branched nonanols such as 3,5,5-trimethylhexan-1-ol and methyloctanols.

[0029] The process of the present invention is preferably a continuous process, in the sense that at least the upstream steps of the reaction route that produce the chemical of interest, including at least step a) and any one of steps b-(i) to (iii) (as long as they are involved in the reaction route), are carried out continuously. In an even more preferred embodiment, all steps of the reaction route that produce the chemical of interest are carried out continuously. This does not exclude the presence of buffer volumes between subsequent reaction steps in the reaction route.

[0030] The present invention is based on the idea of eliminating the impurities inherently present in ethanol from renewable sources during the ethylene manufacturing method itself. Thus, the ethylene from renewable sources or the C 4 - olefin stream from renewable sources produced therefrom can be blended with or interchangeably used with fossil-derived intermediates having the same chemical structure without adjustment in downstream processes.

[0031] It is contemplated that the olefins from renewable sources involved in the process according to the present invention may be blended with complementary olefins from other sources. This can ensure the efficient utilization of downstream processes, for example, during a transitional period when the supply of olefins from renewable sources is limited. These complementary olefins (including complementary ethylene, complementary isobutene, and complementary n-butene) may be fossil-based, partially renewable-source-based, or renewable-source-based through another production route.

[0032] Thus, in an embodiment, the method comprises:

[0033] blending the ethylene from renewable sources with complementary ethylene before step b), where the complementary ethylene is not obtained from renewable-source ethanol according to step a); and / or

[0034] blending the n-butene from renewable sources with complementary n-butene before step b-(ii), b-(iii), or c), where the complementary n-butene is not obtained from renewable-source n-butene according to steps a) and b-(i); and / or

[0035] blending the isobutene from renewable sources with complementary isobutene before step b-(iii) or c), where the complementary isobutene is not obtained from renewable-source n-butene according to steps a), b-(i), and b-(ii).

[0036] Examples of complementary ethylene are ethylene obtained by steam cracking of fossil-based feeds such as naphtha, natural gas, or crude oil. Examples of complementary n-butene are n-butene obtained by steam cracking of fossil-based feeds such as naphtha, natural gas, or crude oil. Examples of complementary isobutene are isobutene obtained by steam cracking of fossil-based feeds such as naphtha, natural gas, or crude oil.

[0037] In another aspect, the present invention also relates to a method for enhancing the environmental sustainability of isononanol, the method comprising blending or replacing a fossil-derived C -4 -olefin stream containing a mixture of n-butene, isobutene, or n-butene and isobutene with a renewable-source C 4 -olefin stream of the same composition to obtain a sustainability-enhanced C 4 -olefin stream, and subjecting the sustainability-enhanced C 4 -olefin stream to a series of chemical conversions to obtain isononanol, wherein the renewable-source C 4 -olefin stream is obtained by

[0038] a) subjecting a feedstock containing renewable-source ethanol to dehydration to produce the ethylene stream from renewable sources; and

[0039] b) subject the ethylene stream from the renewable source to olefin interconversion to obtain a C -4 - olefin stream from the renewable source; the olefin interconversion includes (i) and optionally (ii), or (ii) and (iii):

[0040] (i) dimerize ethylene to obtain n - butene;

[0041] (ii) isomerize the n - butene obtained according to (i) to obtain isobutene;

[0042] (iii) blend the n - butene obtained according to (i) with the isobutene obtained according to (ii);

[0043] This series of chemical conversions includes:

[0044] α) oligomerize the C 4 - olefin stream from the renewable source to produce dibutenes;

[0045] β) subject these dibutenes to a hydroformylation reaction with syngas to obtain isononanal; and

[0046] γ) hydrogenate the isononanal to produce isononanol.

[0047] A key advantage of the process according to the invention is that it can be easily integrated into existing production sites where one or more chemicals of interest are manufactured based on fossil raw materials, in particular naphtha. This means that fossil - based ethylene and C 4 - olefins can be completely or partially replaced by their corresponding ethylene and C 4 - olefins from renewable sources. Thereby, the corresponding chemicals of interest are obtained, the carbon atoms of which are completely or partially based on carbon from renewable sources (so - called "green" carbon).

[0048] Reduced carbon dioxide emissions bring further benefits. The chemical conversions involved in the reaction routes for producing individual chemicals of interest typically have a selectivity of less than 100%. The yield losses are manifested in the production of by - products, which vary depending on the type of reaction involved. For example, oxidation reactions of the substrate to the desired product almost always to some extent involve over - oxidation of the substrate to form carbon oxides, especially carbon dioxide. By completely or partially replacing fossil ethylene and C 4 - olefins with their counterparts from renewable sources, the fossil - based carbon dioxide emissions of the entire production site can be reduced, since the corresponding emissions caused by yield losses along the value chain are at least partially based on green carbon. Thus, the carbon dioxide emissions generated do not contribute to the greenhouse emissions of the production site.

[0049] In addition, in non-oxidation reactions, the various substances present can undergo many side reactions that produce color-forming substances, oligomers, and various decomposition products, etc. These are typically removed during post-treatment, for example by distillation, producing light-boiling and / or high-boiling fractions in addition to the desired product. The light-boiling or high-boiling fractions are conventionally used because of their calorific value, i.e., burned as fuel or developed as a hydrocarbon source, such as a steam cracker feed. It should be understood that completely or partially replacing fossil ethylene and C 4 -olefins at the start of the processing chain reduces the emissions of fossil-based carbon dioxide resulting from the combustion of downstream by-products.

[0050] Thus, it is envisaged that for any chemical of interest manufactured via the process according to the invention, direct and indirect benefits are associated with the process of the invention.

[0051] The expressions "renewable" or "renewable source" with respect to chemical compounds are used synonymously and mean chemical compounds that contain a certain amount of renewable carbon, i.e., have a reduced carbon content of fossil origin or no carbon content of fossil origin. Renewable carbon relates to all carbon sources that avoid or replace the use of any additional fossil carbon from the lithosphere. Renewable carbon can come from the biosphere, the atmosphere, or the technosphere – but not from the lithosphere. Thus, the expressions "renewable" or "renewable source" specifically include biomass-derived chemical compounds. It also includes compounds derived from waste (such as polymer residues) or waste streams derived from chemical production processes.

[0052] The expression "chemical of interest" collectively refers to any desired compound that occurs in the value chain starting from and including ethylene. Thus, this expression includes any intermediate and final product. In some cases, a chemical compound can be both an intermediate and a final product. For example, isobutene can be the final product of the value chain, yet can also be an intermediate if further processed when needed.

[0053] All patent and literature documents mentioned hereinafter are incorporated herein by reference in their entirety.

[0054] Bioethanol is a preferred form of ethanol of renewable source, although the scope of the invention is not limited to the use of bioethanol.

[0055] In the present invention, bioethanol refers to ethanol obtained from biomass feedstocks (such as plants or non-crop feedstocks containing carbon sources that can be converted into ethanol, for example, by microbial metabolism). Typical examples of carbon sources are starch, sugars such as pentoses or hexoses, such as glucose, fructose, sucrose, xylose, arabinose, or degradation products of plants, hydrolysis products of cellulose, or juices of sugarcane, sugar beet, etc. that contain large amounts of the above components.

[0056] Biomass raw materials can be sourced from several origins. Bioethanol production can be based on food crop raw materials such as corn and sugarcane, bagasse, cassava (first-generation bio raw materials).

[0057] Another source of biomass raw materials is lignocellulosic materials from crops (second-generation bio raw materials). Potential raw materials include agricultural residue by-products such as rice, straw (such as wheat, oat, and barley straw), rice husks, and corn stover. Biomass raw materials can also be waste from the forest products industry (wood waste) and sawdust or waste specifically produced as ethanol crops. Switchgrass and elephant grass can be used as dedicated crops for conversion to ethanol.

[0058] First-generation bioethanol is produced in four basic steps:

[0059] (1) Amylase-catalyzed saccharification or hydrolysis into sugars

[0060] (2) Microbial fermentation of sugars

[0061] (3) Purification by distillation to obtain hydrous ethanol

[0062] (4) Dehydration (water removal) to produce anhydrous ethanol

[0063] Second-generation raw materials are considered renewable and sustainable carbon sources. Pretreatment of such raw materials is an essential prerequisite before subjecting them to enzymatic hydrolysis, fermentation, distillation, and dehydration. Pretreatment involves grinding and exposure to acids and heat to reduce the size of plant fibers and hydrolyze a portion of the material to produce fermentable sugars. Saccharification uses enzymes to hydrolyze another portion into sugars. Finally, various sugars (pentoses and hexoses) are converted into ethanol through fermentation by bioengineered microorganisms. The production of bioethanol is well-known and carried out on an industrial scale.

[0064] Ethanol from renewable sources can also be obtained from carbon-containing wastes (such as waste from the chemical industry, garbage, and sewage sludge). The production of ethanol from waste can be accomplished by gasifying it into syngas and catalytically converting the syngas into ethanol, see, for example, Recent Advances in Thermo-Chemical Conversion of Biomass, 2015, pp. 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.

[0065] Dehydration of ethanol from renewable sources

[0066] As a first step, the present invention relates to the dehydration of ethanol from renewable sources. The production of ethylene by catalytic dehydration of ethanol is a well-known method. This reaction is typically carried out at 300 °C to 400 °C and moderate pressure in the presence of a catalyst. The catalysis is reviewed in Ind&Eng Chem Research, 52, 28, 9505-9514 (2013), Materials, 6, 101-115 (2013) and ACS Omega, 2, 4287-4296 (2017). Examples of catalysts are activated alumina or silica, phosphoric acid impregnated on coke, heteropolyacids (HPA salts), silica-alumina, molecular sieves such as zeolites of the ZSM-5 type or SAPO-11 type, other zeolites or modified zeolites of various molecular structures, where zeolites and HPA salts are preferred.

[0067] The dehydration of ethanol is described, for example, 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.

[0068] The ethanol dehydration reaction is typically carried out in the gas phase in contact with a heterogeneous catalyst bed using a fixed bed or fluidized bed reactor. For a fixed bed reactor, the operation can be isothermal (with an external heating system) or adiabatic (in the presence of a heat transfer fluid). The feedstock is vaporized and heated to the desired reaction temperature; as the reaction proceeds in the reactor, the temperature drops. Usually, multiple reactor beds are used in series to maintain the temperature drop in each bed within a controllable range. The cooled effluent from each bed is further heated to reach the desired inlet temperature of the subsequent bed. In addition, a portion of the water is recycled together with the fresh and unreacted ethanol. The presence of water helps to moderate the temperature decrease in each bed.

[0069] Prior to dehydration, the ethanol feedstock from renewable sources can be sent to a pretreatment section to remove mineral contaminants, which would otherwise be harmful to the downstream catalytic reaction. The pretreatment can involve contacting the ethanol feedstock from renewable sources with cation and / or anion exchange resins. After a certain period of operation, the resin can be regenerated by passing a regenerant solution through one or more resin beds to restore its ion exchange capacity. Two sets of beds are preferably operated in parallel to maintain continuous operation. One set of resin beds is appropriately regenerated while the other set of resin beds is used for pretreatment.

[0070] In an isothermal design, the catalyst is placed inside the tubes of a shell-and-tube fixed-bed reactor that is vertically arranged and surrounded by a shell (shell-and-tube design). A heat transfer medium (such as molten salt or oil) circulates inside the shell to provide the required heat. Baffles can be provided on the shell side to promote heat transfer. The cooled heating medium is heated externally and recycled. Compared with an adiabatic reactor, the temperature drop on the process side can be reduced. Better control of the temperature leads to an increase in the selectivity for ethylene formation and a reduction in the amount of unwanted by-products. The temperature is maintained at a roughly constant level within the range of 300 °C to 350 °C. The ethanol conversion is between 98% and 99%, and the selectivity for ethylene is between 94 and 97 mol%. Due to 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, lasting 3 days.

[0071] In an adiabatic design, the endothermic heat of the reaction is supplied by a preheated inert diluent (such as steam). Typically, three fixed-bed reactors can be used, where an intermediate furnace is used to reheat the ethanol / steam mixed feed stream to each reactor. Feeding ethanol together with steam results in less coke formation, longer catalyst activity, and higher yields.

[0072] Another method is the fluidized bed method. The fluidized bed system provides excellent temperature control in the reactor, thus minimizing by-product formation. The heat distribution rate of fluidized bed operation is close to isothermal conditions. The endothermic heat of the reaction is supplied by the hot recycled silica-alumina catalyst returned from the catalyst regenerator. Therefore, external heating of the reactor is not required.

[0073] After dehydration, the reaction mixture is subjected to a separation step. A general separation scheme includes rapidly cooling the reaction gas, for example, in a water quench tower, which separates most of the by-product water and unreacted ethanol from ethylene and other light components, which leave from the top of the quench tower, for example. In one type of separation scheme, the washed ethylene stream is immediately subjected to alkali washing, for example, in a tower, to remove trace amounts of CO 2 . The gaseous stream can enter the compressor directly or first pass through a buffer gas holder and then enter the gas compressor. After compression, the gas is cooled by refrigeration and then passed through an adsorber with, for example, activated carbon, to remove trace amounts of heavy components (such as C4) if they are present. Before the ethylene product leaves the equipment, the adsorber is followed by a desiccant drying and dust filtration step. This separation scheme produces ethylene with a purity of 99%+. If required, the ethylene is further purified by alkali washing and desiccant drying and fractionated in a cryogenic tower to obtain the final product.

[0074] Several commercial processes developed jointly by Braskem, Chematur, British Petroleum (BP), and Axens, in cooperation with Total and the French Institute of Petroleum for Renewable Energies (IFPEN), are currently in operation. These processes differ, for example, in their process conditions, catalysts, and heat integration schemes employed. The process of BP (now Technip) is called Hummingbird. In this process, heteropolyacids are used as catalysts, and the reactor operates at 160 °C to 270 °C and 1 to 45 bar. Unreacted ethanol is recycled to the reactor. The process developed by Axens is called Atol. Two fixed-bed adiabatic reactors operating at 400 °C to 500 °C are used. The process of Chematur operates with four adiabatic tubular reactors. In this process developed by American Halcon Scientific Design, Inc. in the 1980s, a Syndol catalyst with a main component of Al 2 O 3 -MgO / SiO 2 is employed. In the process of Braskem, the adiabatic reactor feed is largely diluted with steam. In this process, the reactor operates at 180 °C to 600 °C, preferably 300 °C to 500 °C, and at 1.9 to 19.6 bar. Alumina or silica-alumina catalysts are used. The process of Braskem is described in more detail in US 4,232,179. Process control according to the process of Braskem is particularly preferred.

[0075] Dimerization of ethylene

[0076] The process of the present invention relates to dimerization of ethylene according to step b)-(i) to obtain n-butene. Any known process can be used for dimerization of ethylene to produce n-butene. A review of dimerization and oligomerization chemistry and technology is given in Catalysis Today, Volume 14 (Issue 1), April 10, 1992.

[0077] Suitably, step b)-(i) comprises:

[0078] - contacting the ethylene stream from the renewable source with a dimerization catalyst in a dimerization zone;

[0079] - operating the dimerization zone under conditions effective to produce an effluent consisting essentially of n-butene, a stream consisting essentially of heavier olefins, and optionally an unreacted ethylene stream; and

[0080] - Fractionate the effluent to recover a stream consisting essentially of n-butene, a stream consisting essentially of heavier olefins, and optionally an ethylene stream.

[0081] The dimerization catalyst can be homogeneous or heterogeneous. Typical dimerization catalysts are titanium or nickel compounds activated with an alkylaluminum compound. Generally, the Ti(IV) valence is stabilized by selecting appropriate ligands, alkylaluminum compounds, solvent polarity, and Al / Ti ratio. Nickel compounds that can catalyze the selective production of butenes are typically cationic nickel salts stabilized with phosphines and activated with an alkylaluminum compound.

[0082] In one embodiment, the oligomerization of ethylene is carried out in a liquid phase containing a nickel compound and an aluminum compound in the presence of a catalytic system. Such catalytic systems are described in documents FR 2 443 877 and FR 2794 038. Dimersol E TM The method is based on this technology and leads to the industrial production of olefins.

[0083] Thus, in one embodiment, the oligomerization of ethylene is carried out in the presence of a catalytic system comprising:

[0084] i) at least one divalent nickel compound,

[0085] ii) at least one hydrocarbyl aluminum dihalide having the formula AlRX 2 wherein R is a hydrocarbyl group containing 1 to 12 carbon atoms, such as an alkyl, aryl, aralkyl, alkaryl, or cycloalkyl group, and X is a chlorine or bromine atom, and

[0086] iii) optionally a Bronsted organic acid.

[0087] As the divalent nickel compound, a nickel carboxylate having the general formula (R 1 COO) 2 Ni is preferably used, wherein R 1 is an optionally substituted hydrocarbyl group, such as an alkyl, cycloalkyl, alkenyl, aryl, aralkyl, or alkaryl group, containing up to 20 carbon atoms, preferably a hydrocarbyl group having 5 to 20 carbon atoms, more preferably 6 to 18 carbon atoms. Suitable divalent nickel compounds include: chlorides, bromides, carboxylates such as octanoate, 2-ethylhexanoate, decanoate, oleate, salicylate, hydroxydecanoate, stearate, phenolates, naphthenates, and acetylacetonates. Nickel 2-ethylhexanoate is preferably used.

[0088] The hydrocarbyl aluminum dihalide compound corresponds to the formula AlRX 2, where R is a hydrocarbon group containing 1 to 12 carbon atoms, such as an alkyl group, an aryl group, an aralkyl group, an alkaryl group or a cycloalkyl group, and X is a chlorine or bromine atom. As examples of such compounds, sesquiethylaluminum chloride, dichloroethylaluminum, dichloroisobutylaluminum, chloro-diethylaluminum or mixtures thereof may be mentioned.

[0089] According to a preferred method, a Bronsted organic acid is used. The Bronsted acid compound corresponds to the formula HY, where Y is an organic anion, such as a carboxyl group, a sulfonic acid group or a phenolic group. Preferably, a halogenated carboxylic acid having the formula R 2 COOH, where R 2 is a haloalkyl group, especially those containing at least one α-halogen atom in the group —COOH having a total of 2 to 10 carbon atoms. Preferably, a halogenated acetic acid having the formula CX p H 3-p —COOH is used, where X is fluorine, chlorine, bromine or iodine, and p is an integer from 1 to 3. By way of example, trifluoroacetic acid, difluoroacetic acid, fluoroacetic acid, trichloroacetic acid, dichloroacetic acid and chloroacetic acid may be cited. Arylsulfonic acids, alkylsulfonic acids and fluoroalkylsulfonic acids, as well as picric acid and nitroacetic acid may also be used. Trifluoroacetic acid is preferably used.

[0090] The three components of the catalytic formulation can be mixed in any order. However, it is preferred to first mix the nickel compound with the Bronsted organic acid and then subsequently introduce the aluminum compound. The molar ratio of the hydrocarbyl aluminum dihalide to the nickel compound, expressed by the Al / Ni ratio, is from 2 / 1 to 50 / 1, and preferably from 2 / 1 to 20 / 1. The molar ratio of the Bronsted acid to the nickel compound is from 0.25 / 1 to 10 / 1, and preferably from 0.25 / 1 to 5 / 1.

[0091] According to a preferred method, the hydrocarbyl aluminum dihalide can be rich in aluminum trihalide, and the mixture of these two compounds then corresponds to the formula AlR n X 3-n , where R is a hydrocarbon group containing 1 to 12 carbon atoms, such as an alkyl group, an aryl group, an aralkyl group, an alkaryl group or a cycloalkyl group, X is a chlorine or bromine atom, and n is a number between 0 and 1. Suitable mixtures include: dichloroethylaluminum rich in aluminum chloride, which mixture has the formula AlEt 0.9 Cl 2.1 ; dichloroisobutylaluminum rich in aluminum chloride, which mixture has the formula AliBu 0.9 Cl 2.1 ; and dibromoethylaluminum rich in aluminum bromide, which mixture has the formula AlEt 0.9 Br 2.1 .

[0092] The reaction for the oligomerization of ethylene can be carried out under pressure conditions at a temperature between -20°C and 80°C, preferably between 40°C and 60°C, such that at least most of the reagents remain in the liquid phase or the condensed phase. The pressure is generally between 0.5 and 5 MPa, preferably between 0.5 MPa and 3.5 MPa. The contact time is generally between 0.5 and 20 hours, preferably between 1 and 15 hours.

[0093] The oligomerization stage can be carried out in a reactor having one or more reaction stages in series, where the ethylene feedstock and / or preferably a pre-conditioned catalytic composition are continuously introduced in the first stage or in the first stage and any other of these stages. At the outlet of the reactor, the catalyst can be deactivated, for example, by injecting ammonia and / or an aqueous solution of soda and / or an aqueous solution of sulfuric acid. Then, by a separation stage, for example, by distillation or by means of a washing cycle with caustic soda and / or water, the unreacted olefins and alkanes optionally present in the feedstock are separated from the oligomers.

[0094] The conversion per pass is generally 85% to 98%. The selectivity for the formation of n-butenes is generally between 50% and 80%. The n-butenes consist of butene-2 (cis- and trans-) and butene-1.

[0095] The effluent generally contains less than 0.2% by weight of isobutene, or even less than 0.1% by weight of isobutene.

[0096] Separation of the n-butene-rich stream

[0097] The effluent obtained by the dimerization of ethylene can be subjected to a separation stage in such a way as to obtain a fraction rich in n-butenes.

[0098] The separation can be carried out by evaporation, distillation, extractive distillation, by solvent extraction or by a combination of these techniques. These methods are known to those skilled in the art. Preferably, the separation of the effluent obtained by the oligomerization of ethylene is carried out by distillation.

[0099] Preferably, the oligomerization effluent is sent to a distillation column system comprising one or more columns which, on the one hand, make it possible to separate the n-butenes from the ethylene (which can be returned to the oligomerization reactor) and the heavier olefins having 5 and more carbon atoms.

[0100] The higher olefins can be subjected to hydrogenation in order to obtain naphtha from renewable sources. "Naphtha from renewable sources" shall mean naphtha produced from renewable sources. It is a hydrocarbon composition mainly consisting of paraffins. The molecular weight range of this naphtha from renewable sources can be hydrocarbons having 5 to 8 carbon atoms. The naphtha from renewable sources can be used as a feedstock in steam cracking to produce light olefins, dienes and aromatic compounds from renewable sources.

[0101] Thus, in an embodiment, step b)-(i) comprises:

[0102] - contacting the ethylene stream from the renewable source with a dimerization catalyst in a dimerization zone;

[0103] - operating the dimerization zone under conditions effective to produce an effluent substantially consisting of n-butenes, a stream substantially consisting of heavier olefins, and optionally an unreacted ethylene stream;

[0104] - fractionating the effluent to recover a stream substantially consisting of n-butenes, a stream substantially consisting of heavier olefins, and optionally an ethylene stream; and

[0105] - optionally subjecting the stream substantially consisting of heavier olefins to hydrogenation to obtain naphtha from the renewable source.

[0106] Skeletal isomerization of n-butenes

[0107] In one aspect, the method of the present invention involves isomerizing the n-butenes obtained according to b)-(i) according to step b)-(ii) to obtain isobutene.

[0108] Since isomerization is an equilibrium reaction, the reaction mixture always contains unreacted n-butenes.

[0109] Suitably, step b)-(ii) comprises:

[0110] - contacting the n-butenes with a skeletal isomerization catalyst in an isomerization zone to produce a mixture of n-butenes and isobutene;

[0111] - recovering a stream substantially consisting of n-butenes and a stream substantially consisting of isobutene from the mixture; and

[0112] - recycling the stream substantially consisting of n-butenes to the isomerization zone.

[0113] A suitable recovery scheme utilizes the reaction of isobutene with an alkanol to produce an alkyl tert-butyl ether. The etherification reaction is selective for isobutene, while n-butenes are unreactive in the reaction. Thus, the reaction can be used as a method for separating n-butenes and isobutene.

[0114] Thus, isobutene can be recovered from a mixture of n-butenes and isobutene by the following steps:

[0115] (a) reacting a mixture of n-butenes and isobutene with isobutanol in the presence of an acidic ion exchange resin in an etherification unit to form a mixture of isobutyl tert-butyl ether (IBTBE) and unreacted n-butenes;

[0116] (b) Distill the reaction mixture in a first distillation unit to obtain an overhead product stream consisting essentially of n-butene and a bottom product containing IBTBE;

[0117] (c) Feed the bottom product to an ether cleavage unit to decompose IBTBE to obtain isobutene and isobutanol;

[0118] (d) Distill the mixture of isobutene and isobutanol produced in step (c) in a second distillation unit to obtain an overhead product stream consisting essentially of isobutene and a bottom product containing isobutanol; and

[0119] (e) Recycle the bottom product of step (d) to step (a).

[0120] Skeletal isomerization generally requires an acidic catalyst. Known skeletal isomerization catalysts include alumina and halogenated alumina, especially F- or Cl-promoted alumina.

[0121] Certain zeolites have been shown to be highly effective in the skeletal isomerization of normal olefins. Such zeolites include those selected from the group consisting of zeolites having the framework structures of ZSM-22, ZSM-23, and ZSM-35.

[0122] Examples of highly selective and highly stable catalysts are chlorinated γ-Al 2 O 3 , ferrierite SAPO-11 (silicoaluminophosphate molecular sieve), and MeAPO-11 (Me = Co, Mn, Mg) (molecular sieve). A particularly preferred catalyst is ferrierite. The typical elemental composition of ferrierite zeolite is Na 2 Mg 2 [Al 6 Si 30 O 72 ·18H 2 O, as disclosed, for example, in US 6323384.

[0123] Spent catalyst can be regenerated by heating in an oxygen-containing gas (such as air) at a temperature in the range of about 200 °C to about 700 °C.

[0124] The skeletal isomerization of n-butene to isobutene is an equilibrium-controlled process, where the equilibrium conversion decreases with increasing temperature.

[0125] Skeletal isomerization is carried out by contacting the feed with a catalyst at a temperature at which skeletal isomerization of the n-butene feed occurs using any suitable contacting technique. The feed is preferably maintained in the gas phase during contact. The reactor temperature is preferably in the range of about 300 °C to about 650 °C, more preferably about 400 °C to about 580 °C. The weight hourly space velocity (WHSV) is not very critical and will generally be in the range of about 0.1 to about 40 h -1 , preferably about 1 to about 20 h -1 . Any convenient pressure can be used, with the lowest practical pressure being preferred to minimize side reactions such as polymerization. The preferred pressure is in the range of about 0.1 to about 10 atmospheres, more preferably about 1 to about 4 atmospheres.

[0126] In the case of a single pass of the feed over the catalyst, equilibrium may not be achieved. However, in a particular variant of the process, the product stream leaving the catalyst bed can be split and only a portion is sent directly to the work-up process while the other portion is recycled over the catalyst bed.

[0127] Several commercial processes for n-butene isomerization are known. In one embodiment, the n-butene feedstock is vaporized by heat exchange with the reactor effluent and further heated to the reaction temperature. In the reactor, the vapor reacts with up to 44% of the n-butene to be converted to isobutene with a selectivity greater than 86%. Typically, two reactors are operated in a cyclic manner: one in the reaction mode and the other in the regeneration mode. The reactor effluent is cooled, compressed and fractionated. The heavy fraction is separated and removed as bottoms from the overhead isobutene product.

[0128] For example, operating conditions, processes and catalyst modifications are disclosed in US 6,111,160 and US 6,323,384. Typical operating conditions are: a reaction temperature of 340 °C - 360 °C, a WHSV of 2 h -1 , an olefin partial pressure of 1 - 2 bar, and a total pressure of 1 - 3 bar.

[0129] C 4 -olefin stream from renewable sources

[0130] The present invention relates to a C 4 -olefin stream from renewable sources suitable for undergoing olefin oligomerization. The C 4 -olefin stream can contain n-butene as the only C 4 -olefin, or isobutene as the only C 4 -olefin, or a mixture of n-butene and isobutene. A C 4 -olefin stream containing a mixture of n-butene and isobutene is obtained by blending the n-butene obtained according to (i) with the isobutene obtained according to (ii) above.

[0131] C 4 The presence of isobutene in the C-olefin stream will result in branched higher olefins, which give rise to branched alcohols. Although highly branched alcohols have relatively little commercial value, a specific degree of branching is often desired.

[0132] Technically, a distinction is usually made between so-called "di-n-butene" (i.e., isomeric C8-olefins, prepared from a mixture of 1-butene and / or 2-butene) and so-called diisobutene (obtained by dimerization of isobutene and exhibiting a higher degree of branching). Di-n-butene is generally considered to be more suitable for the preparation of highly linear oxo alcohols that can be used to prepare plasticizers because of their much lower degree of branching.

[0133] The isomer distribution or degree of branching of isononanol directly affects the properties of the plasticizers produced therefrom by esterification. Esterification with carboxylic acids, especially phthalic acid, is well known. In industry, alcohol mixtures are esterified with phthalic acid or phthalic anhydride. The product diisononyl phthalate (DINP) is used as a plasticizer. The structure of the alcohol, in turn, depends to a large extent on the structure of the parent olefin.

[0134] The effects of increased branching include increased viscosity, increased vapor pressure (which is associated with higher volatility), lower plasticizing efficacy, and the adverse effects of lower thermal and light stability.

[0135] Conversely, high branching also has positive effects: better PVC compatibility, low migration, better hydrolysis resistance, low biodegradability (during the use phase), and high electrical resistance.

[0136] Depending on the intended use, a trade-off must be made. Thus, if the plasticizing effect is crucial, plasticizers with minimal branching will be preferred. Conversely, if the goal is to produce cables covered with PVC, products with a slightly higher degree of branching will be preferred because the electrical insulation will be better.

[0137] The present invention allows the desired degree of branching to be obtained according to the intended use by adjusting the concentration of isobutene in the C-olefin stream. In addition, the present invention allows the butene composition in the butene stream from a steam cracking unit to be simulated. Once a formulation has been developed, it is now necessary to ensure that products with consistent properties are produced during the production process. If isononanol is intended as a partial or complete replacement for isononanol from fossil sources, the butene composition in the C-olefin stream from renewable sources can be made similar to the butene composition in the butene stream from a steam cracking unit. 4 - olefin stream. 4 - olefin stream to be similar to the butene composition in the butene stream from a steam cracking unit.

[0138] In an embodiment, the C-olefin stream from renewable sources contains, relative to the C-olefin stream, C-olefins in the C-olefin stream. 4 - olefin stream 4 - in the olefin stream4 - The total concentration of C4-olefins is 0.2% to 8% by weight of isobutene, preferably 0.5% to 6% by weight of isobutene or 0.5% to 3% by weight of isobutene.

[0139] C4-olefins from renewable sources 4 - The C4-olefin stream can be mixed with an inert diluent (e.g., a saturated hydrocarbon such as butane) and then directed to the oligomerization unit. The olefin content of the butene stream from the steam cracking unit is typically about 60% by weight, with the remainder being saturated hydrocarbons such as butane. Usually, in the production of higher olefins, butane is not removed from the butene stream because a once-through or low recycle oligomerization process is used. Instead, butane is separated from the higher olefin product, which is an easier and less costly separation.

[0140] The process of the present invention provides a C4-olefin stream with a high olefin content. 4 - This enables an oligomerization process with high recycle and low single-pass conversion. The high olefin content allows the olefin concentration in the feed to be maintained at an acceptable level. The low single-pass conversion process results in a higher selectivity for the more desired α-olefins. An α-olefin is an olefin containing a carbon-carbon double bond between the first and second carbons.

[0141] Oligomerization of butene

[0142] Step c) includes the oligomerization of a C4-olefin stream from renewable sources 4 - to produce dibutenes.

[0143] When butene undergoes oligomerization, olefins with eight carbon atoms (C8-olefins, "dibutenes"), olefins with twelve carbon atoms (C12-olefins, "tributenes"), and to a lesser extent olefins with more than twelve carbon atoms (Cn-olefins) are obtained. 8 - olefins, "dibutenes"), olefins with twelve carbon atoms (C12-olefins, "tributenes") 12 - olefins) and, to a lesser extent, olefins containing more than twelve carbon atoms (Cn-olefins). 12+ - olefins).

[0144] The obtained olefin oligomers are separated from each other and from the unreacted C4-olefins 4 - The separation is well known to those skilled in the art and can be accomplished, for example, via two-stage distillation.

[0145] C4-olefins 4 - The oligomerization of the C4-olefin stream can be carried out with a fixed-bed catalyst, at superatmospheric pressure and at room temperature or elevated temperature. The oligomerization is preferably carried out under supercritical conditions with respect to the starting materials. For the oligomerization of C4-olefins, a reaction temperature of preferably 20 °C to 280 °C, more preferably above 160 °C and especially 180 °C to 210 °C is used. 4 - The oligomerization of C4-olefins, a reaction temperature of preferably 20 °C to 280 °C, more preferably above 160 °C and especially 180 °C to 210 °C.

[0146] The reaction pressure is generally from 20 to 300 bar, in particular from 60 to 80 bar. In one embodiment, the oligomerization is carried out at a pressure of from 60 to 300 bar, in particular from 60 to 80 bar, and at a temperature of from 160 °C to 280 °C, in particular from 180 °C to 210 °C. In another embodiment, the oligomerization is carried out at a pressure of from 10 to 30 bar, in particular from 15 to 25 bar, and at a temperature of from 20 °C to 140 °C, in particular from 40 °C to 120 °C.

[0147] After deducting the loss on ignition after heating at 900 °C, the catalyst used typically contains, as active components, from 10% to 70% by weight of nickel oxide (calculated as NiO), from 5% to 30% by weight of titanium dioxide or zirconium dioxide, from 0% to 20% by weight of aluminum oxide, from 20% to 40% by weight of silicon dioxide and from 0.01 to 1 wt.-% of alkali metal oxide, where the contents of the individual components in the catalyst total 100 wt.-%.

[0148] Further details regarding the oligomerization process and the catalyst used are provided in WO 95 / 14647A1 and WO 00 / 63151A1.

[0149] Hydroformylation of dibutene

[0150] The hydroformylation reaction of dibutene with synthesis gas produces isononanal.

[0151] The hydroformylation or oxidation process is an important large-scale industrial process for the preparation of 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. Generally, the hydroformylation is carried out in the presence of a catalyst that is homogeneously dissolved in the reaction medium.

[0152] The catalyst used is generally a carbonyl complex of a metal of transition group VIII (in particular Co, Rh, Ir, Pd, Pt or Ru), which can be unmodified or modified with, for example, amine- or phosphine-containing ligands. However, cocatalysts are preferably used for the hydroformylation of dibutene and tributene. If alcohols with a very low degree of branching are desired, the hydroformylation reaction can preferably be carried out using an unmodified cobalt catalyst. A summary description of the processes practiced on an industrial scale can be found in J. Falbe, “New Syntheses with Carbon Monoxide”, Springer Verlag 1980, pages 162 et seq. Further details can be obtained from US 9,115,069, WO 2001 / 014297, WO 2021 / 197953 and US 6,015,928.

[0153] The hydroformylation of butadiene can be carried out at a temperature in the range of 120 °C to 240 °C, preferably 160 °C to 200 °C. The syngas pressure is typically in the range of 150 to 400 bar, especially 250 to 350 bar. The molar ratio of hydrogen to carbon monoxide in the syngas mixture used is preferably in the range of 70:30 to 50:50, especially 65:35 to 55:45.

[0154] In one embodiment, the hydroformylation reaction is carried out at low pressure, for example at a pressure in the range of 0.05 to 50 MPa (absolute), and preferably at a pressure 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 more than 50% of the total pressure.

[0155] The proportions of carbon monoxide, hydrogen and butadiene in the hydroformylation reaction medium can be selected within a wide range. In some embodiments, based on the total amount of CO, hydrogen and butadiene, CO is about 1 to 50 mol-%, preferably about 1 to 35 mol-%; H 2 is about 1 to 98 mol-%, preferably about 10 to 90 mol-%; and butadiene is about 0.1 to 35 mol-%, preferably about 1 to 35 mol-%.

[0156] The hydroformylation reaction is preferably carried out in the presence of both a liquid phase and a gas phase. The reactants are typically in the gas phase. The catalyst is typically in the liquid phase. Since the reactants are gaseous compounds, a high contact surface area between the gas phase and the liquid phase is desirable to enhance good mass transfer. The high contact surface area between the catalyst solution and the gas phase can be provided in any suitable manner. In a batch process, the batch contents are thoroughly mixed during the reaction. In continuous operation, the reactor feed gas can be contacted with the catalyst solution in, for example, a continuously stirred autoclave, where the gas is preferably introduced through a perforated inlet (e.g., a sprayer) and dispersed at the bottom of the vessel. The high contact between the catalyst and the gas feed can also be provided by dispersing the solution of the Rh catalyst on a high surface area support, which is a technique well known in the art as supported liquid phase catalysis, or by providing Rh as part of a permeable gel.

[0157] The reaction can be carried out in batch mode or preferably on a continuous basis. One or more reactors can be used in continuous mode to carry out the reaction in one or more stages.

[0158] Production of syngas

[0159] The syngas used in the hydroformylation reaction of step β) can be obtained by the following methods:

[0160] - subjecting a gasifier feed stream comprising materials from renewable sources to gasification in a gasifier to obtain a gasifier effluent;

[0161] - recovering syngas from the gasifier effluent.

[0162] Preferably, the feedstock for the gasifier is selected from the group comprising: biomass, municipal solid waste (MSW), shredded residues such as automotive shredded residues, textiles, plastic waste, packaging waste, and mixtures thereof. Such feedstocks may also be mixed with fossil feedstocks such as coal, petroleum, and natural gas. The amount of fossil feedstock is typically not more than 10 wt.-%, preferably not more than 5 wt.-%.

[0163] The term "biomass" includes, but is not limited to, wood, wood pellets, wood chips, straw, lignocellulosic biomass, energy crops, algae, bio-based oils, bio-based fats, and mixtures thereof.

[0164] The term "waste" includes fossil-based waste, bio-based waste, and mixtures thereof. Examples of waste suitable as feedstock are agricultural / farming residues such as wood processing residues, waste wood, logging residues, switchgrass, discarded seed corn, corn stover, and other crop residues, municipal solid waste (MSW), textiles, industrial waste, sewage sludge, plastic waste, packaging waste, shredded residues such as automotive shredded residues, and mixtures thereof.

[0165] Optionally, the feedstock is pretreated before entering the gasifier. Suitable pretreatment methods or combinations of pretreatment methods in the pretreatment unit should provide a sufficiently homogeneous carbon-based feedstock for the gasification reaction and should also be capable of continuously producing syngas by gasification of the feedstock.

[0166] One pretreatment method or a combination of more than one pretreatment method in the pretreatment unit preferably results in homogenization of the physical and / or chemical properties and / or requirements for a particular type of gasifier and / or requirements for at least one additional chemical production unit optionally used for producing a chemical compound or a mixture of chemical compounds.

[0167] The pretreatment method for the first feedstock and / or the second feedstock is preferably selected from the group comprising: drying, grinding, sorting, screening, agglomeration, thermochemical methods, and biological methods.

[0168] Suitable gasifiers include countercurrent fixed bed reactors, cocurrent fixed bed reactors, bubbling fluidized bed reactors, circulating fluidized bed reactors, and downflow or upflow entrained flow reactors. The choice of size and reactor type depends on several parameters, including the composition of the (carbonaceous) feedstock, product requirements, moisture content, and availability of the (carbonaceous) feedstock. Preferably, the gasifier is an "oxygen blown" gasifier, i.e., oxygen is preferably used as the oxidant in the suitable gasifiers listed above.

[0169] The gasification reaction in the gasifier typically takes place at a temperature greater than 700 °C in the presence of a substoichiometric amount of oxidant (such as oxygen, air, steam, supercritical water, CO 2 , or a mixture of the above). Preferably, the gasification takes place at a temperature in the range of greater than 700 °C to 1500 °C, more preferably 850 °C to 1400 °C, even more preferably 1100 °C to 1500 °C. Typically, the gasification takes place at an absolute pressure greater than 1 bar. Preferably, it takes place at an absolute pressure in the range of 2 to 80 bar, more preferably 2 to 50 bar. Oxygen is the most common oxidant used for gasification due to its easy availability and low cost. The H 2 :CO ratio depends on the composition of the feedstock and the amount of steam used in the gasification. The H 2 :CO ratio required for hydroformylation can be adjusted, for example, by selecting an appropriate amount of steam in the gasification.

[0170] Another possibility to adjust the H2:CO ratio is to separate CO from the syngas. CO can be separated from the syngas in a syngas separation unit, which is located downstream of the syngas production unit comprising at least one gasifier and is fluidly connected to the syngas production unit. CO can be separated from the syngas by cryogenic separation methods, which are commonly referred to as "cold boxes", which utilize the different boiling points of CO and H 2 . H 2 Selective membrane separation can be used, through which H 2 permeates and is thus separated from the syngas stream. CO and H 2 can also be completely separated via cryogenic separation. 2 The resulting CO and H 2 can be used to produce syngas with the desired ratio.

[0171] When steam acts as the oxidant, the syngas has a higher molar ratio of H 2 :CO than when air is used as the oxidant. For example, the typical molar ratio range of "air: combined feedstock" is 0.3 to less than 1.

[0172] The conversion of the feedstock in the gasifier produces syngas, which mainly consists of H 2 , CO, CO 2, methane, other hydrocarbons, and impurities. The syngas has a specific molar ratio H of from about 0.1:1 to about 3:1 when leaving the gasifier 2 :CO and depends on the type of solid and / or liquid feedstock used, the oxidant applied, and other reaction conditions such as temperature and / or residence time of the reactants in the gasifier.

[0173] Typical impurities in the raw syngas obtained from the gasification reaction in the gasifier include chlorides, sulfur-containing organic compounds such as sulfur dioxide, trace heavy metals (e.g., as the corresponding salts), and particulate residues. Various chemical and / or physical methods for removing such impurities from the raw syngas, such as filtration, washing, hydrotreating, and absorption / adsorption, are known and can be selected and adjusted according to the type and corresponding concentration of the impurities in the raw syngas and the tolerance to such impurities in successive process steps. Some selected methods for removing impurities from the raw syngas will be discussed in more detail. One or more of such methods can also be implemented in at least one syngas purification unit of a syngas production unit including at least one gasifier. However, the selection of such methods does not limit the scope of the present invention.

[0174] Large particulate impurities can be removed from the raw syngas by a cyclone separator and / or a filter, fine particles and chlorides are removed by wet scrubbing, trace heavy metals, catalytic hydrolysis is used to convert sulfur-containing organic compounds to H 2 S and acid gas removal is used to extract sulfur-containing gases such as H 2 S. Large and fine particles in the syngas can also be removed by quenching in a soot water scrubbing unit.

[0175] The gasification reaction typically produces additional reaction products such as solids and / or highly viscous carbonaceous residues (e.g., char and / or tar), which can be further processed in a separate step not related to the system and method according to the present invention.

[0176] Hydrogenation of isononanal

[0177] The hydrogenation of isononanal produces isononanol. The hydrogenation of isononanal to isononanol is a well-known reaction and can be carried out by any suitable known method.

[0178] In one embodiment, the hydrogenation is carried out with hydrogen in the liquid phase or the gas phase in the presence of a hydrogenation catalyst. Homogeneous or heterogeneous catalysts can be used. Copper catalysts have proven to be the most suitable. Typically, the reaction is carried out in the liquid phase on a fixed-bed catalyst at 50 °C to 250 °C and a pressure of up to 300 bar. The hydrogenation in the gas phase is preferably carried out continuously. The desired isononanol fraction in the reaction effluent obtained during the hydrogenation can be separated by fractional distillation from C 8separated from hydrocarbons and higher-boiling products. Further details can be obtained from Ullmann’s Encyclopedia of Industrial Chemistry, 5th Edition, Volume A1, 1984.

[0179] Production of diesters of adipic acid or phthalic acid

[0180] The present invention further provides a process for producing a diester of adipic acid or phthalic acid, which process comprises subjecting adipic acid, phthalic acid or a derivative thereof to an esterification reaction with isononanol obtained according to any one of the preceding claims.

[0181] Diesters obtained from isononanol and adipic acid or phthalic acid are generally known and are important, for example as plasticizers for the preparation of thermoplastic molding compositions.

[0182] Adipic acid and phthalic acid can be esterified with isononanol in a conventional manner to produce the desired diesters.

[0183] The phthalate according to the invention is preferably prepared using phthalic anhydride. The isononanol obtained as described above is preferably reacted in excess with adipic acid, phthalic acid or a derivative thereof, in particular in a molar excess of 5% to 30%, preferably in the presence of an acylation catalyst such as a dialkyl titanate, for example isopropyl butyl titanate, or an acid such as methanesulfonic acid or sulfuric acid.

[0184] The reaction with adipic acid, phthalic acid or a derivative thereof generally takes place at a temperature of 150 °C to 300 °C, preferably 200 °C to 250 °C. In a suitable embodiment, an inert gas (such as nitrogen) is bubbled through the reaction mixture during the reaction, and the water formed in the reaction is gradually removed from the reaction mixture by means of the inert gas stream. Once the reaction is complete, the diester of adipic acid or phthalic acid is separated from the reaction mixture by, for example, distilling off the excess isononanol in vacuo, neutralizing the crude diester with an aqueous alkali solution (such as an aqueous sodium hydroxide solution), forming a two-phase mixture, separating the aqueous phase and washing the organic phase. For further purification, the neutralized and washed diester is preferably steam-stripped in vacuo at an elevated temperature. The purified diester can then be dried in vacuo at an elevated temperature by passing a nitrogen stream through the mixture and, if desired, further purified by contact with an adsorbent (such as activated carbon or bleaching earth).

[0185] The diisononyl adipate according to the invention prepared in this way has a density of 0.900 to 0.940 g / cm 3 、preferably 0.910 to 0.930 g / cm 3 、in particular 0.918 to 0.922 g / cm 3a density, a viscosity of from 15.0 to 25.0 mPa·s, preferably from 16.0 to 22.0 mPa·s, particularly preferably from 17.0 to 20.0 mPa·s, and a refractive index n of from 1.445 to 1.455, preferably from 1.447 to 1.453, particularly preferably from 1.448 to 1.452 D 20 .

[0186] The diisononyl phthalate according to the invention prepared in this way generally has a density of from 0.950 to 0.990 g / cm 3 , preferably from 0.960 to 0.980 g / cm 3 , in particular from 0.967 to 0.973 g / cm 3 a viscosity of from 60.0 to 110.0 mPa·s, preferably from 63.0 to 80.0 mPa·s, in particular from 65.0 to 75.0 mPa·s, and a refractive index n of from 1.470 to 1.495, preferably from 1.476 to 1.490, in particular from 1.480 to 1.486 D 20 .

Claims

1. A method for manufacturing isononanol, the method comprising the following steps: a) subjecting a feedstock comprising ethanol from renewable sources to dehydration to produce an ethylene stream from renewable sources; b) subject the ethylene stream from the renewable source to olefin metathesis to obtain a C 4 - olefin stream from the renewable source, the C 4 - olefin stream comprising 1-butene, isobutene or a mixture of 1-butene and isobutene; the olefin metathesis comprises (i) and, if desired, (ii), or (ii) and (iii): (i) dimerizing ethylene to obtain n-butene; (ii) isomerizing the n-butene obtained according to (i) to obtain isobutene; (iii) blending the n-butene obtained according to (i) with the isobutene obtained according to (ii); and c) subjecting the C 4 -olefin stream from the renewable source to a series of chemical conversions to obtain isononanol, including: 4 - α) oligomerize the C 4 -olefin olefin stream from the renewable source to produce dibutenes; 4 ​ β) subjecting these dibutenes to a hydroformylation reaction with syngas to obtain isononanal; and γ) hydrogenating the isononanal to produce isononanol.

2. The method according to claim 1, wherein, the syngas in step β) is obtained by: - subjecting a gasifier feed stream comprising materials from renewable sources to gasification in a gasifier to obtain a gasifier effluent; and - recovering syngas from the gasifier effluent.

3. The method according to claim 1 or 2, which comprises blending the ethylene from renewable sources with complementary ethylene before step b), the complementary ethylene not being obtained from ethanol from renewable sources according to step a); and / or blending the n-butene from renewable sources with complementary n-butene before step b-(ii), b-(iii) or c), the complementary n-butene not being obtained from n-butene from renewable sources according to steps a) and b-(i); and / or blending the isobutene from renewable sources with complementary isobutene before step b-(iii) or c), the complementary isobutene not being obtained from n-butene from renewable sources according to steps a), b-(i) and b-(ii).

4. The method according to any one of the preceding claims, wherein, step b)-(i) comprises: - contacting the ethylene stream from renewable sources with a dimerization catalyst in a dimerization zone; - operating the dimerization zone under conditions effective to produce an effluent consisting essentially of n-butene, a stream consisting essentially of heavier olefins, and optionally an unreacted ethylene stream; - fractionating the effluent to recover a stream consisting essentially of n-butene, a stream consisting essentially of heavier olefins, and an optional ethylene stream; and - optionally subjecting the stream consisting essentially of heavier olefins to hydrogenation to obtain naphtha from renewable sources.

5. The method according to any one of the preceding claims, wherein, step b)-(ii) comprises: - subjecting the n-butene to skeletal isomerization to produce a mixture of n-butene and isobutene; - recovering a stream consisting essentially of n-butene and a stream consisting essentially of isobutene from the mixture; and - recycling the stream consisting essentially of n-butene to the skeletal isomerization.

6. A method for producing a diester of adipic acid or phthalic acid, the method comprising subjecting adipic acid, phthalic acid or a derivative thereof to an esterification reaction with isononanol obtained according to any one of the preceding claims.

7. A method for enhancing the environmental sustainability of isononanol, the method comprising blending or replacing a fossil-derived C 4 -olefin stream comprising 1-butene, isobutene, or a mixture of 1-butene and isobutene with a C 4 -olefin stream of the same composition from renewable sources to obtain a C 4 -olefin stream with enhanced sustainability, and subjecting the C 4 -olefin stream with enhanced sustainability to a series of chemical transformations to obtain isononanol, wherein the C 4 -olefin stream from renewable sources is obtained by the following method a) subjecting a feedstock comprising ethanol from renewable sources to dehydration to produce the ethylene stream from renewable sources; and b) subject the ethylene stream from the renewable source to olefin metathesis to obtain a C 4 - olefin stream from the renewable source ； the olefin interconversion includes (i) and optionally (ii), or (ii) and (iii): (i) dimerizing ethylene to obtain n-butene; (ii) Isomerize the 1-butene obtained in (i) to obtain isobutene; (iii) Blend the 1-butene obtained in (i) with the isobutene obtained in (ii); This series of chemical conversions includes: α) Oligomerize the C 4 -olefin olefin stream from the renewable source to produce dibutenes; 4 ​ β) Subjecting these dibutenes to a hydroformylation reaction with syngas to obtain isononanal; and γ) Hydrogenating the isononanal to produce isononanol.