Method for producing conjugated diene polymer

Abstract

To provide a method for producing a nonfossil conjugated diene polymer from a nonfossil raw material-derived alcohol.SOLUTION: A nonfossil conjugated diene polymer is produced from a nonfossil raw material-derived alcohol with an iron content of 0.0001 mg / L or more and 2 mg / L or less.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a method for producing a conjugated diene polymer, more particularly to a method for producing a non-petroleum-derived conjugated diene polymer using as a raw material an alcohol derived from a non-petroleum raw material, such as ethanol, in which the content of specific trace components has been adjusted. [Background technology]

[0002] Petrochemical products are used in many aspects of our lives. However, because they are familiar products, their mass production and mass consumption have caused various environmental problems, which has become a major global issue. For example, polyethylene and polyvinyl chloride, which are representative petrochemical products, are consumed in large quantities and thrown away, and these waste products are a major cause of environmental pollution. In addition, concerns about the depletion of fossil fuel resources and the increase in carbon dioxide in the atmosphere are also being discussed as global environmental problems in the mass production of petrochemical products.

[0003] Due to the growing global awareness of such environmental issues, in recent years, methods for producing various organic substances from raw materials other than naphtha, which is the raw material for petrochemical industrial products, have been considered. For example, a method for producing bioethanol from edible raw materials such as corn by sugar fermentation has attracted attention. However, such sugar fermentation methods using edible raw materials have been pointed out as causing problems such as a rise in food prices because limited agricultural land is used for production other than food.

[0004] In order to solve this problem, the use of non-edible raw materials that have been discarded in the past has also been considered. Specifically, methods have been proposed in which non-edible raw materials such as cellulose derived from waste wood or waste paper are used to produce alcohols by fermentation, and methods have been proposed in which the above-mentioned biomass raw materials are gasified and alcohols are produced from the synthetic gas using a catalyst, but these methods have not yet been put to practical use. Furthermore, even if various petrochemical products can be produced from these non-petroleum raw materials, they will ultimately become waste plastics that do not decompose naturally, so they are not effective as a fundamental solution to environmental problems.

[0005] Incidentally, currently, approximately 60 million tons of combustible waste is disposed of in Japan per year. The amount of energy is equivalent to approximately 200 trillion kilocalories, which is far more than the amount of energy contained in naphtha, the raw material for plastics used in Japan, and this waste can be said to be a valuable resource. If these waste resources could be converted into petrochemical products, it would be possible to realize an ultimate resource-circulating society that is not dependent on petroleum resources. From this perspective, Patent Documents 1 and 2, etc. disclose a technology for producing synthetic gas (gas mainly composed of CO and H2) from waste and producing ethanol from the synthetic gas by fermentation.

[0006] However, as pointed out in Patent Document 3, synthetic gas produced from waste contains a wide variety of impurities that have not been elucidated, some of which are toxic to microorganisms, and therefore the productivity of producing alcohol from synthetic gas by microbial fermentation has been a major issue. In addition, alcohol obtained by microbial fermentation of synthetic gas also contains various components resulting from impurities in the synthetic gas, and these components cannot be completely removed even by purification treatment such as distillation. Therefore, the development of derivatives from alcohol obtained by microbial fermentation of synthetic gas has been a major technical issue.

[0007] Conventionally, synthetic rubbers such as butadiene rubber (BR) and styrene butadiene rubber (SBR) and fillers such as carbon black have been used as rubber compositions for tires, but these have been highly dependent on raw materials derived from petroleum resources. However, in recent years, environmental issues have become important, and regulations on carbon dioxide emissions have been strengthened. Furthermore, since the amount of petroleum currently in existence is finite and there is a limit to the use of raw materials derived from petroleum resources, there is a demand for the development of rubber compositions for tires in which part or all of the currently used raw materials derived from petroleum resources are replaced with raw materials derived from non-petroleum resources. Therefore, Patent Document 4 proposes increasing the ratio of natural rubber as the rubber component. Patent Document 5 proposes using modified natural rubber as the rubber component. Furthermore, Patent Document 6 proposes using renewable (biological resource-derived) butadiene and isoprene as the raw materials for the rubber component, butadiene and isoprene. Patent Documents 7 and 8 propose synthesizing 1,3-butadiene from commercially available bioethanol. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] JP 2016-059296 A [Patent Document 2] International Publication No. 2015-037710 [Patent Document 3] JP 2018-058042 A [Patent Document 4] JP 2007-246712 A [Patent Document 5] JP 2012-122016 A [Patent Document 6] Special Publication No. 2012-518658 [Patent Document 7] International Publication No. 2012 / 102290 [Patent Document 8] JP 2014-148683 A Summary of the Invention [Problem to be solved by the invention]

[0009] According to the study by the present inventors, for example, conventional C2 raw materials such as ethanol are known to be starting materials for various chemical products, but as described above, it has been found that alcohol produced from resources (recyclable resources) that are not based on petroleum resources or biomass resources contains various trace amounts of unknown substances, unlike chemical raw materials derived from naphtha. However, in the conventional technology, the properties of the substances are unknown, and there has been no sufficient consideration in the past as to whether all substances should be removed or only specific substances should be removed. Therefore, even if the above patent documents propose alcohol produced from recyclable resources, there is still room for technical improvement before the alcohol can be put to practical use.

[0010] On the other hand, although the above-mentioned documents disclose general fermentation and distillation methods and the optimal composition of synthetic gas, they do not describe the details of the processes, nor do they specify the alcoholic substance obtained.

[0011] The present invention has been made in view of the above background art, and an object of the present invention is to provide a novel alcohol and its derivatives which are more industrially valuable and practical than existing petrochemical raw materials.

[0012] Patent Document 6 describes a method for producing renewable butadiene in which alcohol obtained by fermenting sugars derived from biomass is used as a starting material. Patent Documents 7 and 8 propose synthesizing 1,3-butadiene from commercially available bioethanol. However, the commercially available alcohols or equivalent products (described in the comparative examples) described in such known documents are not produced with the intention of producing practical chemical products in particular, and it was necessary to develop a raw material alcohol that can withstand the physical properties and characteristics of various practical products (for example, resins and products using the resins). Therefore, a broader technology was required for optimizing the range of application of alcohol. [Means for solving the problem]

[0013] As a result of intensive research to solve the above problems, the present inventors have identified various trace substances contained in alcohol produced from recyclable resources, and further found that it is possible to control the contents within a specific range by a new production method, and further found that various derivatives thereof exhibit superior effects compared to existing alcohols. For example, in the process of synthesizing butadiene from ethanol, the butadiene selectivity is improved compared to the case where conventional ethanol is used, and it has been found that chemical products derived from alcohol or products using the same can be obtained at a practical level equivalent to or more than existing alcohols, and thus the present invention has been completed.

[0014] More specifically, it was found that when ethanol is produced from a gas substrate containing carbon monoxide and hydrogen using waste as a carbon source, the conversion rate of ethanol is improved when butadiene is synthesized from the ethanol, and upon detailed investigation of the reason for this, it was found that ethanol derived from a circulatory resource using a gas substrate containing carbon monoxide and hydrogen has an extremely low content of specific metal elements. The present invention is based on this finding.

[0015] Furthermore, the present inventors conducted intensive research to solve the above problems and found that a conjugated diene such as butadiene can be produced using the above non-petroleum-derived alcohol such as ethanol having an iron content within a specific range as a starting material, and then polymerized to produce a non-petroleum-derived conjugated diene polymer, thereby obtaining a rubber composition suitable for tires. The present invention is based on this finding.

[0016] That is, the present invention includes the following. [1] A method for producing a non-petroleum-derived conjugated diene-based polymer using a non-petroleum-derived alcohol as a raw material, comprising: The method uses non-petroleum-derived alcohol having an iron content of 0.0001 mg / L or more and 2 mg / L or less as a raw material, contacts the alcohol with a catalyst, and heats the alcohol to produce a product having a carbon number of C4 to C6. 12and producing a conjugated diene, a step of polymerizing the monomer containing the conjugated diene to produce a non-petroleum-derived conjugated diene-based polymer; A method comprising: [2] The method according to [1], wherein the alcohol derived from a non-petroleum source comprises ethanol. [3] The method according to [1] or [2], wherein the conjugated diene comprises at least one selected from the group consisting of 1,3-butadiene, isoprene, 1,3-pentadiene, 2,3-dimethyl-1,3-butadiene, 2-methyl-1,3-pentadiene, 1,3-hexadiene, 4,5-diethyl-1,3-octadiene, and 3-butyl-1,3-octadiene. [4] The method according to any one of [1] to [3], wherein the alcohol derived from a non-petroleum raw material is produced using a gas containing carbon monoxide and hydrogen as a substrate. [5] The method according to any one of [1] to [4], wherein the alcohol derived from a non-petroleum raw material is derived from microbial fermentation. [6] The method according to [4], wherein the gas containing carbon monoxide and hydrogen is derived from waste. [7] The method according to any one of [1] to [6], wherein an aromatic hydrocarbon is further polymerized as the monomer. [8] The method according to [7], wherein the aromatic hydrocarbon is at least one selected from the group consisting of styrene, methylstyrene, ethylstyrene, t-butylstyrene, α-methylstyrene, α-methyl-p-methylstyrene, chlorostyrene, bromostyrene, methoxystyrene, dimethylaminomethylstyrene, dimethylaminoethylstyrene, diethylaminomethylstyrene, diethylaminoethylstyrene, cyanoethylstyrene, and vinylnaphthalene. [9] The method according to any one of [1] to [8], wherein the conjugated diene-based polymer contains at least one selected from the group consisting of isoprene rubber, butadiene rubber, styrene butadiene rubber, chloroprene rubber, and acrylonitrile butadiene rubber.

[10] A method for producing a cross-linked rubber product, comprising the steps of: A method comprising the steps of kneading the non-petroleum-derived conjugated diene-based polymer obtained by the method according to any one of [1] to [9] as a rubber component with a filler, and crosslinking the mixture.

[11] A method for producing a tire, using a cross-linked rubber product obtained by the method described in

[10] .

[0017] According to the present invention, by using an alcohol, preferably ethanol, having an extremely low content of a specific metal element, various different effects can be obtained compared to commercially available industrial alcohol. For example, according to the present invention, the butadiene selectivity can be improved when synthesizing butadiene using ethanol as a raw material, the yield can be improved when synthesizing SBR, and the glass transition temperature of SBR and the butadiene / styrene ratio can be controlled. In addition, it is expected that the same effects can be obtained by adjusting the content of a specific metal element to an extremely low content even for existing alcohols.

[0018] In addition, the alcohol used in the present invention, preferably ethanol, can be used as a raw material for the production of, for example, butadiene, ethylene, propylene, isobutene, acetaldehyde, acetic acid, ethyl acetate, methyl (meth)acrylate, ethyl-t-butyl ether ethylene glycol, ester compositions, polyesters, acrylic acid, aminohexanoic acid, diethyl carbonate, polyethylene (PE), polyethylene terephthalate (PET), polypropylene (PP), polyisobutylene, polymethyl methacrylate (PMMA), ethylene propylene diene rubber (EPDM), polybutylene terephthalate (PBT), polyethylene furanoate (PEF), polyurethane (PU), etc. In addition, the alcohol used in the present invention can be used for various applications of chemical products such as cosmetics, perfumes, fuels, antifreeze, bactericides, disinfectants, cleaning agents, mold removers, detergents, hair washes, soaps, antiperspirants, face wash sheets, solvents, paints, adhesives, diluents, and food additives. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] Hereinafter, an example of a preferred embodiment of the present invention will be described. However, the following embodiment is merely an example for explaining the present invention, and the present invention is not limited to the following embodiment.

[0020] <Definition> In the present invention, the term "alcohol" refers to a compound in which a hydrogen atom of a hydrocarbon is replaced with a hydroxyl group (-OH). Specifically, examples of lower alcohols include methanol (methyl alcohol), ethanol (ethyl alcohol), 2-propanol, ethylene glycol, glycerin, and phenol, and preferably ethanol. Furthermore, examples of higher alcohols include those having usually 8 to 22 carbon atoms, and specifically include capryl alcohol, lauryl alcohol, myristyl alcohol, cetyl alcohol (cetanol), stearyl alcohol, oleyl alcohol, and linolyl alcohol. In addition, in the present invention, "ethanol" does not mean pure ethanol as a compound (ethanol represented by the chemical formula: CH3CH2OH), but means a composition that contains water and impurities (contaminant components) that are inevitably contained in ethanol produced through synthesis or purification. In the present invention, the content of each component, such as an inorganic component or an organic component, in the alcohol raw material refers to the amount (mg) of each component per 1 L of alcohol.

[0021] <Alcohol derived from non-petroleum raw materials> In the present invention, alcohol derived from a non-petroleum raw material with a controlled Fe (iron) content is used. Specifically, the Fe (iron) content is 0.0001 mg / L or more and 2 mg / L or less, preferably 0.0005 mg / L or more, more preferably 0.001 mg / L or more, even more preferably 0.01 mg / L or more, preferably 1.5 mg / L or less, more preferably 1.0 mg / L or less, and even more preferably 0.5 mg / L or less, relative to the alcohol. The Fe content is the amount of Fe compound converted into Fe element. The Fe content within the above range can improve the butadiene selectivity, particularly when synthesizing butadiene using ethanol as a raw material, improve the yield when synthesizing SBR, and enable control of the glass transition temperature of SBR and the butadiene / styrene ratio.

[0022] The iron content in alcohol can be measured by a conventional method. For example, the iron content can be measured by an inductively coupled plasma mass spectrometry (ICP-MS) analysis method. In the ICP-MS analysis method, the concentration of the standard solution for atomic absorption is adjusted, then a calibration curve is created, and the iron content is determined by analyzing the sample to be measured based on this calibration curve.

[0023] The alcohol, preferably ethanol, used in the present invention is not particularly limited, but is preferably an alcohol produced using a gas containing carbon monoxide and hydrogen as a substrate, or an alcohol produced using microbial fermentation or a metal catalyst using sugar or cellulose as a raw material. This is because it is easy to adjust the iron content to the above concentration in these alcohols in the production process. In addition, it has been found that commercially available non-fossil fuel-derived, for example, sugar ethanol, particularly small-scale reagent ethanol as described in publicly known documents, does not contain Fe as described in the comparative examples. Therefore, for the purpose of industrial use as a chemical raw material, strict control of the Fe content becomes necessary. In such a case, the iron content may be adjusted to the above concentration by further purification, preferably the purification method described in this specification. If iron is not contained in an amount exceeding the above concentration, it is sufficient to include it in the process of producing ethanol from a raw material and / or the process of converting ethanol into a conjugated diene, and the timing of including it is not particularly limited, but includes storage, transportation, and delivery. The method of including it is not particularly limited, but may be, for example, addition or elution upon contact with a metal containing Fe.

[0024] Without being bound by theory, in the present invention, by reducing the content of a specific metal in ethanol to an extremely low value, it becomes possible to improve the butadiene selectivity when synthesizing butadiene using ethanol as a raw material, to improve the yield when synthesizing SBR, and to control the glass transition temperature of SBR and the butadiene / styrene ratio.

[0025] The alcohol, particularly ethanol, used in the present invention may contain inorganic components other than Fe. For example, it may contain inorganic components such as Si, K, and Na. Compounds containing these elements may be inorganic compounds or organometallic compounds.

[0026] When alcohol, particularly ethanol, contains Si, the Si content is preferably 10 mg / L or more, more preferably 20 mg / L or more, even more preferably 30 mg / L or more, and preferably 100 mg / L or less, more preferably 90 mg / L or less, and even more preferably 80 mg / L or less, relative to ethanol. The Si content is the Si element equivalent of the Si compound. When the Si content is within the above numerical range, water generated by the butadiene synthesis reaction can be supplemented, and therefore the butadiene selectivity when synthesizing butadiene using ethanol as a raw material can be improved, and the yield of the butadiene polymerization reaction can be improved.

[0027] The content of Si in alcohol, particularly ethanol, can be measured by a conventional method. For example, the method of measuring the content of Si includes a method of analysis using an inductively coupled plasma mass spectrometry (ICP-MS). In the method of analysis using ICP-MS, a standard solution for atomic absorption is analyzed after concentration adjustment to create a calibration curve, and the content of Si is obtained by analyzing the sample to be measured based on this calibration curve.

[0028] The alcohol, particularly ethanol, of the present invention is obtained by extracting and further purifying the ethanol-containing liquid obtained from the microbial fermenter as described below, and may contain other components in addition to the above-mentioned unavoidable substances. For example, it may contain a trace amount of aromatic compounds. Examples of aromatic compounds include toluene, ethylbenzene, o-xylene, m-xylene, and p-xylene, and only one of these may be contained, or two or more of these may be contained. It is preferable that the aromatic compound contains ethylbenzene.

[0029] The content (total) of aromatic compounds contained in alcohol, particularly ethanol, is preferably 0.4 mg / L or more, more preferably 0.5 mg / L or more, even more preferably 0.7 mg / L or more, even more preferably 1.0 mg / L or more, and also preferably 10 mg / L or less, more preferably 7 mg / L or less, even more preferably 5 mg / L or less, and even more preferably 3 mg / L or less, based on the total ethanol. When the content of aromatic compounds is within the above numerical range, mixing of styrene and ethanol during polymerization reaction becomes smooth, and the yield of polymerization reaction is improved.

[0030] The content of aromatic compounds in alcohol, particularly ethanol, can be measured by a conventionally known method. For example, the method of measuring the content of aromatic compounds includes a method of analysis using gas chromatography mass spectrometry (GC-MS). In the method of analysis using GC-MS, a standard gas is analyzed to create a calibration curve, and the content of aromatic compounds is determined by analyzing the sample to be measured based on this calibration curve.

[0031] When ethylbenzene is contained in alcohol, particularly ethanol, the content of ethylbenzene is preferably 0.1 mg / L or more, more preferably 0.2 mg / L or more, even more preferably 0.3 mg / L or more, even more preferably 0.5 mg / L or more, and also preferably 5 mg / L or less, more preferably 3 mg / L or less, even more preferably 2 mg / L or less, and even more preferably 1 mg / L or less, based on the total ethanol. By having the content of ethylbenzene within the above numerical range, mixing of styrene and ethanol during the polymerization reaction becomes smooth, and the yield of the polymerization reaction is improved.

[0032] The content of ethylbenzene in alcohol, particularly ethanol, can be measured by a conventionally known method. For example, the method of measuring the content of ethylbenzene includes a method of analysis using gas chromatography mass spectrometry (GC-MS). In the method of analysis using GC-MS, a standard gas is analyzed to create a calibration curve, and the ethylbenzene content is determined by analyzing the sample to be measured based on this calibration curve.

[0033] When toluene is contained in alcohol, particularly ethanol, the toluene content is preferably 0.01 mg / L or more, more preferably 0.02 mg / L or more, even more preferably 0.03 mg / L or more, even more preferably 0.05 mg / L or more, and preferably 1 mg / L or less, more preferably 0.5 mg / L or less, even more preferably 0.2 mg / L or less, and even more preferably 0.1 mg / L or less, based on the total ethanol. By having the toluene content within the above numerical range, mixing of styrene and ethanol during the polymerization reaction becomes smooth, and the yield of the polymerization reaction is improved.

[0034] The content of toluene in ethanol can be measured by a conventional method. For example, the method of measuring the content of toluene includes a method of analysis using gas chromatography mass spectrometry (GC-MS). In the method of analysis using GC-MS, a standard gas is analyzed to create a calibration curve, and the content of toluene is determined by analyzing the sample to be measured based on this calibration curve.

[0035] When o-xylene is contained in alcohol, particularly ethanol, the content of o-xylene is preferably 0.1 mg / L or more, more preferably 0.2 mg / L or more, even more preferably 0.3 mg / L or more, even more preferably 0.5 mg / L or more, and preferably 5 mg / L or less, more preferably 3 mg / L or less, even more preferably 2 mg / L or less, and even more preferably 1 mg / L or less, based on the total ethanol. When the content of o-xylene is within the above numerical range, mixing of styrene and ethanol during the polymerization reaction becomes smooth, and the yield of the polymerization reaction is improved.

[0036] The content of o-xylene in alcohol, particularly ethanol, can be measured by a conventionally known method. For example, the method of measuring the content of o-xylene includes a method of analysis using gas chromatography mass spectrometry (GC-MS). In the method of analysis using GC-MS, a calibration curve is prepared by analyzing a standard gas, and the content of o-xylene is obtained by analyzing a sample to be measured based on this calibration curve.

[0037] When m-xylene and / or p-xylene are contained in alcohol, particularly ethanol, the content (total) of m-xylene and / or p-xylene relative to the total ethanol is preferably 0.1 mg / L or more, more preferably 0.2 mg / L or more, and also preferably 5 mg / L or less, more preferably 3 mg / L or less, even more preferably 2 mg / L or less, and even more preferably 1 mg / L or less. When the content of m-xylene and / or p-xylene is within the above numerical range, mixing of styrene and ethanol during the polymerization reaction is smooth, and the yield of the polymerization reaction is improved.

[0038] The content of m- or p-xylene in alcohol, particularly ethanol, can be measured by a conventionally known method. For example, the method of measuring the content of m- or p-xylene includes a method of analysis using gas chromatography mass spectrometry (GC-MS). In the method of analysis using GC-MS, a calibration curve is prepared by analyzing a standard gas, and the content of m- or p-xylene is determined by analyzing a sample to be measured based on this calibration curve.

[0039] When chlorine is contained in alcohol, particularly ethanol, it is preferable that the chlorine content is less than 2 mg / L. If the chlorine content exceeds the above range, the catalyst for the reaction of synthesizing butadiene from ethanol is deactivated, and the conversion rate of ethanol decreases.

[0040] The content of chlorine in alcohol, particularly ethanol, can be measured by a conventional method.The method of measuring the content of chlorine can be, for example, a method of analysis using ion chromatography.In the method of analysis using ion chromatography, a standard solution is analyzed to create a calibration curve, and the content of chlorine is obtained by analyzing the sample to be measured based on this calibration curve.

[0041] The alcohol, particularly ethanol, of the present invention contains the inorganic components described above, and, if desired, trace amounts of organic components such as aromatic hydrocarbons and aliphatic hydrocarbons. The concentration of ethanol, which is the main component in ethanol (pure ethanol as a compound), is 75% by volume or more, preferably 80% by volume or more, more preferably 90% by volume or more, even more preferably 95% by volume or more, still more preferably 98% by volume or more, and is preferably 99.999% by volume or less, more preferably 99.99% by volume or less, even more preferably 99.9% by volume or less, and still more preferably 99.5% by volume or less.

[0042] <How alcohol is produced> The method for producing alcohol, particularly ethanol, having the above-mentioned specific inorganic and organic compounds is not particularly limited as long as the content is within the range specified in the present invention. However, the raw material for alcohol includes biomass resources, specifically, for example, cellulosic plants (pulp, waste paper, paper, etc.), wood, charcoal, compost, natural rubber, cotton, sugarcane, soybean pulp, oils and fats, plants (corn, cassava, bagasse, etc.), fishery residues, livestock waste, waste, algae, etc. The biomass resources may be those extracted and refined from the above-mentioned biomass resources or biomass resources subjected to the above-mentioned treatment (i.e., biomass-derived substances). For example, sugar ethanol refined from these biomass resources may be used. Ethanol can be produced by microbial fermentation of synthetic gas containing carbon monoxide derived from waste or exhaust gas. In such a method, the content of aromatic compounds and the like in the raw gas derived from waste or exhaust gas and the refining conditions may be controlled to control the amount of aromatic compounds contained in the final product. Hereinafter, as an example, a method for producing ethanol by microbial fermentation of synthetic gas containing carbon monoxide derived from waste or exhaust gas will be described.

[0043] The method for producing alcohol, particularly ethanol, includes the steps of converting a carbon source into a synthesis gas containing carbon monoxide and hydrogen, a microbial fermentation step of supplying the synthesis gas containing carbon monoxide and hydrogen to a microbial fermenter to obtain an ethanol-containing liquid by microbial fermentation, a separation step of separating the ethanol-containing liquid into a liquid or solid component containing microorganisms and a gas component containing ethanol, a liquefaction step of condensing and liquefying the gas component, and a purification step of purifying ethanol from the liquid obtained in the liquefaction step, but may also include a raw material gas generation step, a synthesis gas preparation step, a wastewater treatment step, etc., as necessary. Each step will be described below.

[0044] <Raw material gas generation process> The raw gas generation process is a process of generating raw gas by gasifying a carbon source in a gasification section. A gasification furnace may be used in the raw gas generation process. The gasification furnace is a furnace that burns (incompletely combusts) a carbon source, and examples of such furnaces include shaft furnaces, kiln furnaces, fluidized bed furnaces, and gasification reforming furnaces. The gasification furnace is preferably a fluidized bed furnace type, since it can achieve high hearth load and excellent operability by partially burning waste. By gasifying the waste in a fluidized bed furnace at low temperature (about 450 to 600 ° C) and in a low-oxygen atmosphere, the waste is decomposed into gas (carbon monoxide, carbon dioxide, hydrogen, methane, etc.) and char containing a large amount of carbon. Furthermore, since the non-combustible materials contained in the waste are separated from the bottom of the furnace in a hygienic and low-oxidization state, it is possible to selectively recover valuable materials such as iron and aluminum from the non-combustible materials. Therefore, such gasification of waste allows efficient resource recycling.

[0045] The gasification temperature in the raw material gas production step is not particularly limited, but is usually 100 to 2500°C, and preferably 200 to 2100°C.

[0046] The reaction time for gasification in the raw material gas generation step is usually 2 seconds or more, and preferably 5 seconds or more.

[0047] The carbon source used in the raw material gas production process is not particularly limited, and various carbon-containing materials can be suitably used for the purpose of recycling, such as coke ovens in steelworks, blast furnaces (blast furnace gas), coal used in converters and coal-fired power plants, general waste and industrial waste introduced into incinerators (particularly gasifiers), and carbon dioxide by-produced by various industries.

[0048] More specifically, the carbon source is preferably waste material, and specific examples thereof include plastic waste, food waste, municipal solid waste (MSW), industrial solid waste, discarded tires, biomass waste, household waste such as bedding and paper, waste materials such as building materials, coal, petroleum, petroleum-derived compounds, natural gas, shale gas, and the like. Among these, various types of waste are preferable, and from the viewpoint of sorting costs, unsorted municipal solid waste is more preferable.

[0049] In addition, the carbon source can be, for example, waste tires as a combustion material, specifically, gas generated when waste tires are burned and the thermal energy generated at that time is recovered, such as in thermal recycling. The combustion device is not particularly limited, but examples include the blast furnaces of steel mills, blast furnaces (blast furnace gas), converters, coal used in coal-fired power plants, incinerators, boilers, etc., as described above. In particular, about 60% of the raw material of tires is suitable for combustion materials, and tire chips obtained from waste tires have a total calorific value of 35,000 kJ per kg, which is almost the same as petroleum products such as light oil and heavy oil, so they are suitable as alternative fuels to coal and the like. In other words, if CO2 is the main gas, the gas generated by these can be converted to CO using known technology and used, which is an effective measure to reduce CO2, and therefore is preferable because it can achieve resource circulation type recycling.

[0050] The feed gas obtained by gasifying the carbon source contains carbon monoxide and hydrogen as essential components, but may further contain carbon dioxide, oxygen, and nitrogen. As other components, the feed gas may further contain components such as soot, tar, nitrogen compounds, sulfur compounds, phosphorus compounds, and aromatic compounds.

[0051] In the above-mentioned raw material gas production step, the raw material gas may be produced by carrying out a heat treatment (commonly known as gasification) to combust (incompletely combust) a carbon source, i.e., by partially oxidizing the carbon source, as a gas containing carbon monoxide in an amount of, although not particularly limited, 0.1 vol % or more, preferably 10 vol % or more, and more preferably 20 vol % or more.

[0052] <Synthetic gas refining process> The synthesis gas purification process is a process for removing or reducing specific substances such as various pollutants, dust particles, impurities, and undesirable amounts of compounds from the raw gas. When the raw gas is derived from waste, the raw gas usually contains carbon monoxide at 0.1% to 80% by volume, carbon dioxide at 0.1% to 70% by volume, and hydrogen at 0.1% to 80% by volume, and further tends to contain nitrogen compounds at 1 mg / L or more, sulfur compounds at 1 mg / L or more, phosphorus compounds at 0.1 mg / L or more, and / or aromatic compounds at 10 mg / L or more. In addition, other environmental pollutants, dust particles, impurities, and other substances may be contained. Therefore, when supplying synthesis gas to a microbial fermenter, it is preferable to reduce or remove substances and compounds that are undesirable for stable cultivation of microorganisms from the raw gas, and to make the content of each component contained in the raw gas within a range suitable for stable cultivation of microorganisms.

[0053] In particular, in the synthesis gas purification process, a pressure swing adsorption apparatus filled with the above-mentioned regenerated adsorbent is used to adsorb carbon dioxide gas in the synthesis gas onto the regenerated adsorbent (zeolite), thereby reducing the carbon dioxide gas concentration in the synthesis gas. Furthermore, the synthesis gas may be subjected to other conventionally known treatment processes to remove impurities and adjust the gas composition. As other treatment processes, for example, one or more of a gas chiller (moisture separator), a low-temperature separation type (cryogenic type) separator, a particulate (soot) separator such as a cyclone or a bag filter, a scrubber (water-soluble impurity separator), a desulfurization device (sulfide separator), a membrane separation type separator, a deoxygenation device, a pressure swing adsorption type separator (PSA), a temperature swing adsorption type separator (TSA), a pressure temperature swing adsorption type separator (PTSA), a separator using activated carbon, and a deoxygenation catalyst, specifically, a separator using a copper catalyst or a palladium catalyst, etc. may be used for treatment.

[0054] In the present invention, the concentrations of iron and chromium derived from the raw gas can be controlled by adjusting the conditions of the above-mentioned treatment process. For example, by adjusting the conditions of the residence time of the scrubber and membrane separation, these concentrations can be reduced to below the detection limit. By reducing the concentrations of iron and chromium in the raw gas in this way, the contents of iron and chromium in the final alcohol, particularly ethanol, can be reduced to below the detection limit.

[0055] The synthesis gas used in the method for producing alcohol, particularly ethanol, of the present invention contains at least carbon monoxide as an essential component, and may further contain hydrogen, carbon dioxide, and nitrogen.

[0056] The synthesis gas used in the present invention may be a gas obtained by generating a raw material gas by gasifying a carbon source (raw material gas generation process), and then adjusting the concentrations of each component of carbon monoxide, carbon dioxide, hydrogen and nitrogen from the raw material gas, as well as reducing or removing the above-mentioned substances and compounds, and the gas obtained may be used as the synthesis gas.

[0057] The carbon monoxide concentration in the synthesis gas is usually 20 vol.% or more and 80 vol.% or less, preferably 25 vol.% or more and 50 vol.% or less, and more preferably 35 vol.% or more and 45 vol.% or less, based on the total concentration of carbon monoxide, carbon dioxide, hydrogen, and nitrogen in the synthesis gas.

[0058] The hydrogen concentration in the synthesis gas is usually 10 vol. % or more and 80 vol. % or less, preferably 30 vol. % or more and 55 vol. % or less, and more preferably 40 vol. % or more and 50 vol. % or less, based on the total concentration of carbon monoxide, carbon dioxide, hydrogen, and nitrogen in the synthesis gas.

[0059] The carbon dioxide concentration in the synthesis gas is usually 0.1 vol.% or more and 40 vol.% or less, preferably 0.3 vol.% or more and 30 vol.% or less, more preferably 0.5 vol.% or more and 10 vol.% or less, and particularly preferably 1 vol.% or more and 6 vol.% or less, based on the total concentration of carbon monoxide, carbon dioxide, hydrogen, and nitrogen in the synthesis gas.

[0060] The nitrogen concentration in the synthesis gas is usually 40 vol. % or less, preferably 1 vol. % or more and 20 vol. % or less, and more preferably 5 vol. % or more and 15 vol. % or less, based on the total concentration of carbon monoxide, carbon dioxide, hydrogen, and nitrogen in the synthesis gas.

[0061] The concentrations of carbon monoxide, carbon dioxide, hydrogen, and nitrogen can be set within a predetermined range by changing the elemental composition of the hydrocarbons (carbon and hydrogen) and nitrogen in the carbon source in the raw gas generation process, or by appropriately changing the combustion conditions such as the combustion temperature and the oxygen concentration of the gas supplied during combustion. For example, if you want to change the carbon monoxide or hydrogen concentration, you can change the carbon source to one with a higher ratio of hydrocarbons (carbon and hydrogen), such as waste plastics, and if you want to lower the nitrogen concentration, you can supply a gas with a high oxygen concentration in the raw gas generation process.

[0062] The synthetic gas used in the present invention may contain, in addition to the above-mentioned components, sulfur compounds, phosphorus compounds, nitrogen compounds, etc., without any particular limitation. The content of each of these compounds is preferably 0.05 mg / L or more, more preferably 0.1 mg / L or more, even more preferably 0.5 mg / L or more, and is preferably 2000 mg / L or less, more preferably 1000 mg / L or less, even more preferably 80 mg / L or less, even more preferably 60 mg / L or less, and particularly preferably 40 mg / L or less. By setting the content of sulfur compounds, phosphorus compounds, nitrogen compounds, etc. to the lower limit value or more, there is an advantage that microorganisms can be suitably cultured, and by setting the content to the upper limit value or less, there is an advantage that the medium is not contaminated by various nutrient sources not consumed by the microorganisms.

[0063] Examples of sulfur compounds include sulfur dioxide, CS2, COS, and H2S, and among them, H2S and sulfur dioxide are preferred because they are easily consumed as a nutrient source for microorganisms. Therefore, it is more preferable that the sum of H2S and sulfur dioxide is contained in the synthesis gas within the above range. As the phosphorus compound, phosphoric acid is preferred because it is easily consumed as a nutrient source for microorganisms, and therefore it is more preferred that the synthesis gas contains phosphoric acid in the above range. Examples of the nitrogen compound include nitric oxide, nitrogen dioxide, acrylonitrile, acetonitrile, HCN, etc., and HCN is preferred because it is easily consumed as a nutrient source for microorganisms. Therefore, it is more preferable that HCN is contained in the synthesis gas in the above range.

[0064] The synthetic gas may contain aromatic compounds in an amount of 0.01 mg / L or more and 90 mg / L or less, preferably 0.03 mg / L or more, more preferably 0.05 mg / L or more, and even more preferably 0.1 mg / L or more, and preferably 70 mg / L or less, more preferably 50 mg / L or less, and even more preferably 30 mg / L or less. By making the content equal to or more than the lower limit, microorganisms tend to be cultured favorably, and by making the content equal to or less than the upper limit, the medium tends to be less likely to be contaminated by various nutrient sources not consumed by the microorganisms.

[0065] <Microbial fermentation process> The microbial fermentation step is a step of producing alcohol, particularly ethanol, by microbial fermentation of the synthesis gas in a microbial fermenter. The microbial fermenter is preferably a continuous fermentation apparatus. In general, any shape of microbial fermenter can be used, including stirring type, airlift type, bubble column type, loop type, open bond type, and photobio type. In the present invention, the microbial fermenter can be suitably a known loop reactor having a main tank section and a reflux section. In this case, it is preferable to further include a circulation step of circulating the liquid medium between the main tank section and the reflux section.

[0066] As long as the synthesis gas to be supplied to the microbial fermenter satisfies the above-mentioned compositional conditions of the synthesis gas, the gas obtained through the raw material gas generation process may be used as the synthesis gas as it is, or another specified gas may be added to the gas obtained by reducing or removing impurities from the raw material gas, and then the synthesis gas may be used. As the other specified gas, at least one compound selected from the group consisting of sulfur compounds such as sulfur dioxide, phosphorus compounds, and nitrogen compounds may be added to prepare the synthesis gas.

[0067] The microbial fermenter may be continuously supplied with the synthesis gas and the microbial culture liquid, but it is not necessary to supply the synthesis gas and the microbial culture liquid simultaneously, and the synthesis gas may be supplied to a microbial fermenter to which the microbial culture liquid has been previously supplied. It is known that certain anaerobic microorganisms produce alcohol, particularly ethanol, from substrate gases such as synthesis gas by fermentation, and this type of gas-utilizing microorganism is cultured in a liquid medium. For example, a liquid medium and gas-utilizing bacteria may be supplied and accommodated, and the synthesis gas may be supplied into the microbial fermenter while stirring the liquid medium in this state. This allows the gas-utilizing bacteria to be cultured in the liquid medium, and ethanol to be produced from the synthesis gas by the fermentation action.

[0068] In the microbial fermenter, the temperature of the medium etc. (culture temperature) may be any temperature, but is preferably about 30 to 45° C., more preferably about 33 to 42° C., and even more preferably about 36.5 to 37.5° C. The culture time is preferably 12 hours or more in continuous culture, more preferably 7 days or more, particularly preferably 30 days or more, and most preferably 60 days or more. Although there is no particular upper limit, from the viewpoint of regular maintenance of the equipment, it is preferably 720 days or less, and more preferably 365 days or less. The culture time means the time from adding the seed bacteria to the culture tank to discharging the entire amount of the culture liquid in the culture tank.

[0069] The microorganism (species) contained in the microbial culture solution is not particularly limited as long as it can produce ethanol by microbial fermentation of synthetic gas using carbon monoxide as the main raw material. For example, the microorganism (species) is preferably one that produces ethanol from synthetic gas by the fermentation action of gas-utilizing bacteria, and is particularly preferably a microorganism having a metabolic pathway of acetyl-CoA. Among gas-utilizing bacteria, the genus Clostridium is more preferable, and Clostridium autoethanogenum is particularly preferable, but is not limited thereto. Further examples are given below.

[0070] Gas-utilizing bacteria include both eubacteria and archaea. Examples of eubacteria include bacteria of the genus Clostridium, Moorella, Acetobacterium, Carboxydocella, Rhodopseudomonas, Eubacterium, Butyribacterium, Oligotropha, Bradyrhizobium, and aerobic hydrogen-oxidizing bacteria such as Larsotonia.

[0071] On the other hand, examples of archaea include bacteria of the genus Methanobacterium, bacteria of the genus Methanobrevibacter, bacteria of the genus Methanocalculus, bacteria of the genus Methanococcus, bacteria of the genus Methanosarcina, bacteria of the genus Methanosphaera, bacteria of the genus Methanothermobacter, Metha Examples include bacteria of the genus Nothrix, bacteria of the genus Methanoculleus, bacteria of the genus Methanofollis, bacteria of the genus Methanogenium, bacteria of the genus Methanospirillium, bacteria of the genus Methanosaeta, bacteria of the genus Thermococcus, bacteria of the genus Thermofilum, bacteria of the genus Arcaheoglobus, and the like. Among these, as archaea, bacteria of the genus Methanosarcina, bacteria of the genus Methanococcus, bacteria of the genus Methanothermobacter, bacteria of the genus Methanothrix, bacteria of the genus Thermococcus, bacteria of the genus Thermofilum, and bacteria of the genus Archaeoglobus are preferred.

[0072] Furthermore, because of their excellent carbon monoxide and carbon dioxide assimilation ability, archaea are preferably Methanosarcina bacteria, Methanothermobactor bacteria, or Methanococcus bacteria, and more preferably Methanosarcina bacteria or Methanococcus bacteria. Specific examples of Methanosarcina bacteria include Methanosarcina barkeri, Methanosarcina mazei, and Methanosarcina acetivorans.

[0073] Among the above-mentioned gas-utilizing bacteria, bacteria with high ethanol production ability are selected and used. For example, gas-utilizing bacteria with high ethanol production ability include Clostridium autoethanogenum, Clostridium ljungdahlii, Clostridium aceticum, Clostridium carboxidivorans, Moorella thermoacetica, Acetobacterium woodii, etc., among which Clostridium autoethanogenum is particularly preferred.

[0074] The medium used to culture the above-mentioned microorganisms (species) is not particularly limited as long as it has an appropriate composition according to the bacteria, but is a liquid containing water as the main component and nutrients (e.g., vitamins, phosphoric acid, etc.) dissolved or dispersed in the water. The composition of such a medium is prepared so that gas-utilizing bacteria can grow well. For example, when the genus Clostridium is used as the microorganism, the medium can be prepared by referring to U.S. Patent Application Publication No. 2017 / 260552, paragraphs "0097" to "0099", etc.

[0075] The alcohol-containing liquid, particularly the ethanol-containing liquid, obtained by the microbial fermentation process can be obtained as a suspension containing microorganisms and their carcasses, proteins derived from the microorganisms, etc. The protein concentration in the suspension varies depending on the type of microorganism, but is usually 30 to 1000 mg / L. The protein concentration in the ethanol-containing liquid can be measured by the Kjeldahl method.

[0076] <Separation process> The alcohol-containing liquid, particularly the ethanol-containing liquid, obtained by the microbial fermentation process is then subjected to a separation process. In the present invention, the ethanol-containing liquid is heated to room temperature to 500° C. under conditions of 0.01 to 1000 kPa (absolute pressure) to separate into a liquid or solid component containing microorganisms and a gas component containing ethanol. In the conventional method, the ethanol-containing liquid obtained by the microbial fermentation process is distilled to separate and purify the desired ethanol, but since the ethanol-containing liquid contains microorganisms and proteins derived from microorganisms, if the ethanol-containing liquid is distilled as it is, foaming may occur in the distillation apparatus, hindering continuous operation. In addition, it is known to use a membrane evaporator as a method for purifying a foamable liquid, but the membrane evaporator has low concentration efficiency and is not suitable for purifying a liquid containing a solid component. In the present invention, before separating and purifying the desired ethanol from the ethanol-containing liquid obtained by the microbial fermentation process by a distillation operation or the like, the ethanol-containing liquid is heated to separate into a liquid or solid component containing microorganisms and a gas component containing ethanol, and the desired ethanol is separated and purified only from the separated gas component containing ethanol. By carrying out the separation step, foaming does not occur in the distillation apparatus during the distillation operation for separating and purifying ethanol, so that the distillation operation can be carried out continuously. Also, since the ethanol concentration in the gaseous component containing ethanol becomes higher than the ethanol concentration in the ethanol-containing liquid, the separation and purification of ethanol can be efficiently carried out in the purification step described later.

[0077] In the present invention, from the viewpoint of efficiently separating the ethanol-containing liquid into a liquid or solid component containing microorganisms, their carcasses, proteins derived from microorganisms, etc., and a gaseous component containing ethanol, the ethanol-containing liquid is heated preferably under conditions of 10 to 200 kPa, more preferably under conditions of 50 to 150 kPa, and even more preferably at normal pressure, at a temperature of preferably 50 to 200°C, more preferably at a temperature of 80°C to 180°C, and even more preferably at a temperature of 100 to 150°C.

[0078] The heating time in the separation step is not particularly limited as long as it is a time that allows the production of gaseous components, but from the standpoint of efficiency or economy, it is usually 5 seconds to 2 hours, preferably 5 seconds to 1 hour, and more preferably 5 seconds to 30 minutes.

[0079] In the above-mentioned separation step, any device can be used without particular limitation as long as it can efficiently separate the ethanol-containing liquid into liquid or solid components (microorganisms or their carcasses, proteins derived from microorganisms, etc.) and gas components (ethanol) by thermal energy, and for example, drying devices such as rotary dryers, fluidized bed dryers, vacuum dryers, and conductive heating dryers can be used, but it is preferable to use a conductive heating dryer from the viewpoint of efficiency in separating an ethanol-containing liquid with a low solid component concentration into liquid or solid components and gas components. Examples of conductive heating dryers include drum dryers and disk dryers.

[0080] <Liquefaction process> The liquefaction step is a step of liquefying the gaseous components containing alcohol, particularly ethanol, obtained in the separation step by condensation. The device used in the liquefaction step is not particularly limited, but it is preferable to use a heat exchanger, particularly a condenser. Examples of the condenser include a water-cooled type, an air-cooled type, and an evaporative type, and among these, a water-cooled type is preferable. The condenser may be a single-stage condenser or a multi-stage condenser.

[0081] It is preferable that the liquefied product obtained by the liquefaction step does not contain components contained in the ethanol-containing liquid, such as microorganisms, their remains, and proteins derived from microorganisms, but the present invention does not exclude the inclusion of proteins in the liquefied product. Even if the liquefied product contains proteins, the concentration of the proteins is preferably 40 mg / L or less, more preferably 20 mg / L or less, and even more preferably 15 mg / L or less.

[0082] The heat of condensation of the gas components obtained by the condenser may be reused as a heat source in the purification step described below. By reusing the heat of condensation, ethanol can be produced efficiently and economically.

[0083] <Purification process> Next, alcohol is purified from the liquefied product obtained in the liquefaction step. This production method varies depending on the alcohol, but there is no particular restriction as long as the specific compound specified in the present invention is limited to a specific content. The purification step for ethanol is described in detail below. The ethanol-containing liquid obtained in the microbial fermentation step can be supplied to the purification step without going through the above-mentioned separation step if components such as microorganisms have already been removed. The purification step is a step of separating the ethanol-containing liquid obtained in the liquefaction step into a distillate having an increased concentration of the target ethanol and a bottoms liquid having a decreased concentration of the target ethanol. In addition, the purification step described in this specification may be performed in order to produce the ethanol specified in the present invention even in ethanol produced from sources other than the synthetic gas as described above or commercially available bioethanol. Examples of the apparatus used in the purification step include a distillation apparatus, a treatment apparatus including a pervaporation membrane, a treatment apparatus including a zeolite dehydration membrane, a treatment apparatus for removing low-boiling substances having a boiling point lower than that of ethanol, a treatment apparatus for removing high-boiling substances having a boiling point higher than that of ethanol, and a treatment apparatus including an ion exchange membrane. These apparatuses may be used alone or in combination of two or more. As the unit operation, thermal distillation or membrane separation may be suitably used.

[0084] In the heat distillation, a distillation apparatus is used to obtain the desired ethanol as a distillate with high purity. The temperature in the distillation apparatus during the distillation of ethanol is not particularly limited, but is preferably 100°C or less, and more preferably about 70 to 95°C. By setting the temperature in the distillation apparatus within the above range, separation of ethanol from other components, i.e., distillation of ethanol, can be performed more reliably. In particular, the ethanol-containing liquid obtained in the liquefaction step is introduced into a distillation apparatus equipped with a heater using steam at 100°C or more, and the temperature of the bottom of the distillation column is increased to 90°C or more within 30 minutes, and then the ethanol-containing liquid is introduced from the middle of the distillation column, and the distillation step is performed with the temperature difference between the bottom, middle, and top of the column being within ±15°C, thereby obtaining high-purity ethanol. The distillation temperature difference is preferably ±13°C, more preferably ±11°C. The above distillation temperature difference allows separation from other components, i.e., distillation of ethanol, to be performed more reliably, and is preferable for producing ethanol as specified in the present invention.

[0085] Without being bound by theory, it is believed that the ethanol-containing liquid contains Si in the form of organosiloxanes (e.g., 1,1,3,3-tetramethyldisiloxane, hexamethyldisiloxane, etc.) with a boiling point of 100° C. or less. The ethanol obtained by distilling such ethanol can contain a trace amount of Si by leaving organosiloxanes with a boiling point close to that of ethanol. In the present invention, the Si content in the ethanol contained in the distillate can be adjusted by adjusting the above distillation conditions. As a result, the Si content in the final ethanol can be adjusted. Note that in the above separation step, the gas introduction temperature into the separation device is kept at 20° C. to 40° C. to stabilize the organosiloxanes in the synthesis gas, thereby adjusting the Si content in the final ethanol.

[0086] As the distillation apparatus, it is preferable to use a plurality of distillation columns. In this case, it is preferable to use a treatment device including an ion exchange membrane between the distillation columns. In the present invention, the sodium ion and potassium ion concentrations are controlled by passing through the ion exchange membrane, so that the sodium content and potassium content in the final ethanol can be adjusted to a suitable range.

[0087] The ethanol-containing liquid is considered to contain aliphatic hydrocarbons (e.g., heptane, octane, decane, dodecane, tetradecane, etc.) having a boiling point higher than that of ethanol, aromatic compounds (e.g., toluene, ethylbenzene, xylene, etc.), and dialkyl ethers (e.g., dibutyl ether, dipentyl ether, etc.). In the present invention, by adjusting the above distillation conditions, for example, by increasing the temperature at the top of the distillation column by 5 to 10°C or higher than usual, aromatic compounds are also distilled, and the aromatic compounds in the ethanol contained in the distillate can be adjusted. As a result, the content of aromatic compounds in the final ethanol can be adjusted.

[0088] The pressure in the distillation apparatus during the distillation of ethanol may be normal pressure, but is preferably less than atmospheric pressure, more preferably about 60 to 95 kPa (absolute pressure). By setting the pressure in the distillation apparatus within the above range, the separation efficiency of ethanol can be improved, and the ethanol yield can be improved, which is preferable for producing the ethanol specified in the invention. The ethanol yield (the concentration of ethanol contained in the distillate after distillation) is preferably 90% by volume or more, more preferably 95% by volume or more.

[0089] In the membrane separation, a known separation membrane can be appropriately used, and for example, a zeolite membrane can be suitably used.

[0090] The concentration of ethanol contained in the distillate separated in the purification step is preferably 20% by volume to 99.99% by volume, and more preferably 60% by volume to 99.9% by volume. On the other hand, the concentration of ethanol contained in the bottoms is preferably 0.001% by volume to 10% by volume, and more preferably 0.01% by volume to 5% by volume.

[0091] The bottoms separated in the purification step are substantially free of nitrogen compounds. In the present invention, "substantially free" does not mean that the concentration of nitrogen compounds is 0 mg / L, but means that the bottoms obtained in the purification step have a nitrogen compound concentration at a level that does not require a wastewater treatment step. In the separation step, the ethanol-containing liquid obtained in the microbial fermentation step is not purified to obtain the desired ethanol, but the ethanol-containing liquid is separated into a liquid or solid component containing a microorganism and a gaseous component containing ethanol as described above. At that time, the nitrogen compounds remain on the liquid or solid component side containing a microorganism, so that the gaseous component containing ethanol contains almost no nitrogen compounds. Therefore, it is considered that the bottoms obtained when ethanol is purified from a liquefied product obtained by liquefying a gaseous component does not substantially contain nitrogen compounds. Even if the bottoms contain nitrogen compounds, the concentration of the nitrogen compounds is 0.1 to 200 mg / L, preferably 0.1 to 100 mg / L, and more preferably 0.1 to 50 mg / L.

[0092] For the same reason as above, the bottoms separated in the purification step are substantially free of phosphorus compounds. Note that "substantially free" does not mean that the concentration of phosphorus compounds is 0 mg / L, but means that the bottoms obtained in the purification step have a phosphorus compound concentration of such a level that a wastewater treatment step is not required. Even if the bottoms contain phosphorus compounds, the concentration of phosphorus compounds is 0.1 to 100 mg / L, preferably 0.1 to 50 mg / L, and more preferably 0.1 to 25 mg / L. Thus, according to the method of the present invention, the bottoms discharged in the ethanol purification step are substantially free of nitrogen compounds and phosphorus compounds, and are considered to contain almost no other organic matter, so that the wastewater treatment step that has been required in the past can be simplified.

[0093] <Wastewater treatment process> The bottoms separated in the refining step may be supplied to a wastewater treatment step. In the wastewater treatment step, organic matter such as nitrogen compounds and phosphorus compounds can be further removed from the bottoms. In this step, the bottoms may be subjected to anaerobic or aerobic treatment to remove the organic matter. The removed organic matter may be used as fuel (heat source) in the refining step.

[0094] The treatment temperature in the wastewater treatment step is usually 0 to 90°C, preferably 20 to 40°C, and more preferably 30 to 40°C.

[0095] The bottoms obtained through the separation process have had liquid and solid components, including microorganisms, removed, and therefore require less wastewater treatment and other processes than the bottoms obtained by directly supplying the bottoms from the microbial fermentation process to the purification process.

[0096] In the wastewater treatment process, the nitrogen compound concentration in the treatment liquid obtained by treating the bottoms is preferably 0.1 to 30 mg / L, more preferably 0.1 to 20 mg / L, and even more preferably 0.1 to 10 mg / L, and it is particularly preferable that no nitrogen compounds are contained in the treatment liquid. The phosphorus compound concentration in the treatment liquid is preferably 0.1 to 10 mg / L, more preferably 0.1 to 5 mg / L, and even more preferably 0.1 to 1 mg / L, and it is particularly preferable that no phosphorus compounds are contained in the bottoms.

[0097] <Uses of alcohol> Below, we will explain as an example the method of synthesizing butadiene using alcohol, particularly ethanol, as a raw material according to the present invention, and the method of producing styrene-butadiene rubber (SBR). However, it goes without saying that the method can also be used for chemical products and polymer raw materials that use other conjugated diene compounds.

[0098] <Method of synthesizing 1,3-butadiene> Butadiene is produced by refining the C4 fraction, which is a by-product when ethylene is synthesized from petroleum (i.e., naphtha cracking), and is a raw material for synthetic rubber. However, in recent years, there has been a strong demand for a technology to convert ethanol (ethanol derived from microbial fermentation) that is not derived from fossil fuels into 1,3-butadiene instead of chemical industrial raw materials obtained from petroleum. As a method for synthesizing butadiene using such ethanol derived from microbial fermentation as a raw material, a method using MgO as a catalyst, a method using a mixture of Al2O3 and ZnO, a catalyst having a magnesium silicate structure, and the like are known. In addition to the above, hafnium, vanadium, manganese, iron, cobalt, nickel, copper, zinc, gallium, niobium, silver, indium, cerium, and the like are used as catalysts.

[0099] By contacting the ethanol of the present invention with the above-mentioned catalyst and heating it, an ethanol conversion reaction occurs, and 1,3-butadiene can be synthesized. By synthesizing 1,3-butadiene using the ethanol of the present invention as a raw material, it is possible to realize an ultimate resource-recycling society that is not dependent on petroleum resources.

[0100] The heating temperature for promoting the conversion reaction is, for example, about 200 to 450°C, preferably about 300 to 400°C, in the reaction system. If the temperature in the reaction system is below the above range, the catalytic activity is not sufficient, and the reaction rate tends to decrease, resulting in a decrease in production efficiency. On the other hand, if the temperature in the reaction system is above the above range, the catalyst may be easily deteriorated.

[0101] The reaction can be carried out by a conventional method such as a batch method, a semi-batch method, or a continuous method. When a batch method or a semi-batch method is adopted, the conversion rate of ethanol can be increased, but when the ethanol according to the present invention is used, ethanol can be converted more efficiently than before, even when a continuous method is adopted. The reason for this is not clear, but it is thought to be due to the fact that the ethanol derived from a circulatory resource such as that of the present invention, which uses a gas containing carbon monoxide and hydrogen as a substrate, has a unique peak in a gas chromatograph measured by gas chromatography mass spectrometry, which is not seen in ethanol derived from fossil fuels.

[0102] Examples of the method for contacting the raw material with the catalyst include a suspension bed method, a fluidized bed method, and a fixed bed method. Either a gas phase method or a liquid phase method may be used. In terms of easy recovery and regeneration of the catalyst, it is preferable to use a fixed bed type gas phase continuous flow reactor in which the catalyst is packed in a reaction tube to form a catalyst layer, and the raw material is passed through as a gas to react in the gas phase. When the reaction is carried out in the gas phase, the ethanol of the present invention may be gasified and supplied to the reactor without dilution, or may be appropriately diluted with an inert gas such as nitrogen, helium, argon, or carbon dioxide gas and then supplied to the reactor.

[0103] After the ethanol conversion reaction is completed, the reaction product (1,3-butadiene) can be separated and purified by, for example, a method of performing gas-liquid separation at 10°C and extracting only the gas, a method of contacting with a drying material such as calcium chloride or a molecular sieve, a separation means such as filtration, concentration, distillation, extraction, or a separation means combining these.

[0104] The purity of the obtained butadiene is preferably 70% or more, more preferably 75% or more, even more preferably 80% or more, and even more preferably 82% or more. This is because the yield of the polymerization reaction is improved. The purity of butadiene can be calculated by the following formula. Butadiene purity = butadiene concentration / total organic compound purity The ratio of the concentration of the obtained butadiene to the concentration of the oxygen-containing compound is preferably 3 or more. This is to prevent the deactivation of the catalyst used in the polymerization reaction. The ratio of the concentration of the butadiene to the concentration of the oxygen-containing compound can be calculated by the following formula. Butadiene / oxygenated compounds = butadiene concentration / (ethanol concentration + acetaldehyde concentration + acetic acid concentration + ethyl acetate concentration + diethyl ether concentration) The ratio of the concentration of the obtained butadiene to the concentration of the hydrocarbon compound is preferably 5 or more. This is to increase the purity of the polymer. The ratio of the concentration of the butadiene to the concentration of the hydrocarbon compound can be calculated by the following formula. Butadiene / Hydrocarbon compounds = butadiene concentration / (ethylene concentration + butene concentration + propylene concentration + butane concentration)

[0105] <Method of producing conjugated diene polymer> The method for producing a conjugated diene polymer of the present invention comprises the steps of: The method uses non-petroleum-derived alcohol having an iron content of 0.0001 mg / L or more and 2 mg / L or less as a raw material, contacts the alcohol with a catalyst, and heats the alcohol to produce a product having a carbon number of C4 to C6. 12 and producing a conjugated diene, a step of polymerizing the monomer containing the conjugated diene to produce a non-petroleum-derived conjugated diene-based polymer; It includes.

[0106] The raw material used in the process for producing conjugated dienes is not particularly limited as long as it is an alcohol derived from a non-petroleum raw material and has an iron content of 0.0001 mg / L or more and 2 mg / L or less. For example, the above-mentioned ethanol can be used.

[0107] The number of carbon atoms obtained in the production process of conjugated dienes is C4 to C 12Examples of the conjugated diene include 1,3-butadiene, isoprene, 1,3-pentadiene, 2,3-dimethyl-1,3-butadiene, 2-methyl-1,3-pentadiene, 1,3-hexadiene, 4,5-diethyl-1,3-octadiene, and 3-butyl-1,3-octadiene. Among these, 1,3-butadiene is preferred. These conjugated dienes may be used alone or in combination of two or more in the production process of the non-petrochemical-derived conjugated diene-based polymer.

[0108] In the manufacturing process of conjugated diene polymers, the monomers used are those with carbon numbers of C4 to C 12 Only the conjugated diene may be used, or aromatic hydrocarbons other than the conjugated diene may be used. Examples of aromatic hydrocarbons used as monomers include styrene, methylstyrene, ethylstyrene, t-butylstyrene, α-methylstyrene, α-methyl-p-methylstyrene, chlorostyrene, bromostyrene, methoxystyrene, dimethylaminomethylstyrene, dimethylaminoethylstyrene, diethylaminomethylstyrene, diethylaminoethylstyrene, cyanoethylstyrene, and vinylnaphthalene. Among these, styrene is preferred.

[0109] In the process for producing a conjugated diene polymer, the polymerization method of the monomer is not particularly limited, and polymerization can be performed by a conventionally known method. The polymerization method may be emulsion polymerization or solution polymerization. Emulsion polymerization is a method in which a monomer that is poorly soluble in a conventionally known solvent such as water and an emulsifier (surfactant) are mixed in the solvent, and a polymerization initiator that is soluble in the solvent is further added to perform polymerization. Solution polymerization is a method in which a monomer and a polymerization initiator are added to an inert solvent to perform polymerization.

[0110] The surfactant used in the production process of the conjugated diene polymer is not particularly limited as long as it is one that is usually used in emulsion polymerization. Specific examples of the surfactant that can be used include cationic surfactants and anionic surfactants.

[0111] In the process for producing conjugated dienes, the catalyst is not particularly limited, and a conventionally known catalyst can be used. For example, as the polymerization catalyst, it is preferable to use a catalyst containing a rare earth element-containing compound, a coordination catalyst using a metallocene catalyst, or an anionic polymerization catalyst using an organic metal compound.

[0112] The inert solvent used in the production process of the conjugated diene polymer is not particularly limited as long as it is a solvent that is usually used in solution polymerization and does not inhibit the polymerization reaction. Specific examples of the inert solvent include chain aliphatic hydrocarbons such as butane, pentane, hexane, and heptane; alicyclic hydrocarbons such as cyclopentane and cyclohexane; aromatic hydrocarbons such as benzene, toluene, and xylene; and the like. These inert solvents may be used alone or in combination of two or more.

[0113] The polymerization initiator used in the production process of conjugated diene polymers is a polymer having a carbon number of C4 to C 12There is no particular limitation as long as it can polymerize a monomer containing a conjugated diene of the formula (I). Specific examples of the polymerization initiator include an organic alkali metal compound, an organic alkaline earth metal compound, and a polymerization initiator using a lanthanum series metal compound as a main catalyst. Examples of the organic alkali metal compound include organic monolithium compounds such as n-butyl lithium, sec-butyl lithium, t-butyl lithium, hexyl lithium, phenyl lithium, and stilbene lithium; organic polyvalent lithium compounds such as dilithiomethane, 1,4-dilithiobutane, 1,4-dilithio-2-ethylcyclohexane, 1,3,5-trilithiobenzene, and 1,3,5-tris(lithiomethyl)benzene; organic sodium compounds such as sodium naphthalene; and organic potassium compounds such as potassium naphthalene. Examples of organic alkaline earth metal compounds include di-n-butyl magnesium, di-n-hexyl magnesium, diethoxy calcium, calcium distearate, di-t-butoxy strontium, diethoxy barium, diisopropoxy barium, diethylmercapto barium, di-t-butoxy barium, diphenoxy barium, diethylamino barium, barium distearate, diketyl barium, etc. Examples of polymerization initiators using a lanthanum series metal compound as a main catalyst include polymerization initiators using a lanthanum series metal salt consisting of a lanthanum series metal such as lanthanum, cerium, praseodymium, neodymium, samarium, gadolinium, etc., a carboxylic acid, and a phosphorus-containing organic acid, etc., as a main catalyst, and a co-catalyst such as an alkyl aluminum compound, an organoaluminum hydride compound, an organoaluminum halide compound, etc. Among these polymerization initiators, organic monolithium compounds and organic polyvalent lithium compounds are preferably used, organic monolithium compounds are more preferably used, and n-butyllithium is particularly preferably used. The organic alkali metal compounds may be reacted in advance with secondary amine compounds such as dibutylamine, dihexylamine, dibenzylamine, pyrrolidine, piperidine, hexamethyleneimine, and heptamethyleneimine to be used as organic alkali metal amide compounds.By using an organic alkali metal amide compound as a polymerization initiator, the obtained cross-linked rubber product can have low heat generation and excellent wet grip properties. These polymerization initiators may be used alone or in combination of two or more.

[0114] The amount of the polymerization initiator used may be determined depending on the molecular weight of the desired conjugated diene polymer, but is usually in the range of 1 to 50 mmol, preferably 1.5 to 20 mmol, and more preferably 2 to 15 mmol per 1000 g of monomer.

[0115] The polymerization temperature is usually in the range of −80 to +150° C., preferably 0 to 100° C., and more preferably 30 to 90° C. As the polymerization mode, any mode such as a batch mode or a continuous mode can be adopted, but when a conjugated diene compound and an aromatic vinyl compound are copolymerized, the batch mode is preferred in that it is easy to control the randomness of the bonds between the conjugated diene monomer units and the aromatic vinyl monomer units.

[0116] Examples of the conjugated diene polymer obtained by the production method of the present invention include isoprene rubber (IR), butadiene rubber (BR), styrene butadiene rubber (SBR), chloroprene rubber (CR), and acrylonitrile butadiene rubber (NBR). Among these, styrene butadiene rubber is preferred as a rubber component for use in tires.

[0117] The weight average molecular weight (Mw) of the conjugated diene polymer obtained by the production method of the present invention is not particularly limited, but is preferably 100,000 to 2,000,000, more preferably 150,000 to 1,500,000, and particularly preferably 200,000 to 1,000,000, as a value measured by gel permeation chromatography in terms of polystyrene. By setting the weight average molecular weight (Mw) of the conjugated diene polymer having an active end within the above range, the obtained cross-linked rubber product can have a good balance between wet grip properties and low heat build-up.

[0118] The molecular weight distribution of the conjugated diene polymer obtained by the production method of the present invention, represented by the ratio (Mw / Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn), is not particularly limited, but is preferably 4.0 to 6.0, and more preferably 4.7 to 6.0. When the molecular weight distribution (Mw / Mn) of the conjugated diene polymer is within the above range, the low heat build-up property of the obtained cross-linked rubber can be further improved.

[0119] The glass transition temperature (Tg) of the conjugated diene polymer obtained by the production method of the present invention is not particularly limited, but is preferably −40° C. to −50° C., and more preferably −41° C. to −47° C. The glass transition temperature of the conjugated diene polymer obtained by the production method of the present invention can be adjusted, for example, by changing the blending ratio of the conjugated diene monomer and the aromatic hydrocarbon monomer in the conjugated diene polymer.

[0120] The conjugated diene polymer thus obtained by the production method of the present invention can be suitably used for various applications after adding a filler, a crosslinking agent, etc. In particular, when silica is blended as a filler, a rubber composition can be obtained that can give a crosslinked rubber product having low heat buildup and excellent wet grip properties.

[0121] <Rubber composition> The rubber composition of the present invention contains, as a rubber component, the conjugated diene polymer obtained by the above-mentioned production method of the present invention and a filler. The filler is not particularly limited, and examples thereof include silica, carbon black, calcium carbonate, and talc.

[0122] Examples of silica to be blended in the rubber composition include dry process white carbon, wet process white carbon, colloidal silica, precipitated silica, and the like. Among these, wet process white carbon containing hydrated silicic acid as the main component is preferred. Carbon-silica dual phase filler in which silica is supported on the surface of carbon black may also be used. These silicas may be used alone or in combination of two or more. The nitrogen adsorption specific surface area of ​​the silica used (measured by the BET method in accordance with ASTM D3037-81) is preferably 50 to 300 m 2 / g, more preferably 80 to 220m 2 The pH of the silica is preferably 5 to 10.

[0123] The amount of silica in the rubber composition is 10 to 200 parts by weight, preferably 30 to 150 parts by weight, and more preferably 50 to 100 parts by weight, based on 100 parts by weight of the rubber component in the rubber composition. By setting the amount of silica in the above range, the processability of the rubber composition becomes excellent, and the wet grip property and low heat build-up property of the obtained cross-linked rubber can be further improved.

[0124] The method of adding silica to the rubber composition is not particularly limited, and may include a method of adding silica to a solid conjugated diene polymer and kneading it (dry kneading method), or a method of adding silica to a solution containing a conjugated diene polymer and coagulating and drying it (wet kneading method).

[0125] The carbon black to be blended in the rubber composition is not particularly limited, and examples thereof include furnace black, acetylene black, thermal black, channel black, graphite, etc. Blending of carbon black provides reinforcing properties, and in particular can improve abrasion resistance.

[0126] The rubber composition of the present invention may further contain a silane coupling agent from the viewpoint of further improving low heat generation. The silane coupling agent is not particularly limited, and various silane coupling agents can be used. As the silane coupling agent, any silane coupling agent that has been conventionally used in combination with silica in the rubber industry can be used, and examples of the silane coupling agent include bis(3-triethoxysilylpropyl)tetrasulfide, bis(2-triethoxysilylethyl)tetrasulfide, bis(4-triethoxysilylbutyl)tetrasulfide, bis(3-trimethoxysilylpropyl)tetrasulfide, bis(2-trimethoxysilylethyl)tetrasulfide, bis(4-trimethoxysilylbutyl)tetrasulfide, bis(3-triethoxysilylpropyl)trisulfide, bis(2-triethoxysilylethyl)trisulfide, and bis(4-trimethoxysilylbutyl)tetrasulfide. Examples of the silane coupling agent include sulfide-based crosslinking accelerators such as bis(4-triethoxysilylbutyl) trisulfide, bis(3-trimethoxysilylpropyl) trisulfide, bis(2-trimethoxysilylethyl) trisulfide, bis(4-trimethoxysilylbutyl) trisulfide, bis(3-triethoxysilylpropyl) disulfide, bis(2-triethoxysilylethyl) disulfide, bis(4-triethoxysilylbutyl) disulfide, bis(3-trimethoxysilylpropyl) disulfide, bis(2-trimethoxysilylethyl) disulfide, and bis(4-trimethoxysilylbutyl) disulfide. Among these, bis(3-triethoxysilylpropyl) disulfide is preferred from the viewpoint of processability. These silane coupling agents may be used alone or in combination of two or more.

[0127] The rubber composition preferably further contains a crosslinking agent. Examples of the crosslinking agent include sulfur, halogenated sulfur, organic peroxides, quinone dioximes, organic polyamine compounds, and alkylphenol resins having a methylol group. Among these, sulfur is preferably used. The amount of the crosslinking agent is preferably 0.1 to 15 parts by weight, more preferably 0.5 to 5 parts by weight, and particularly preferably 1 to 4 parts by weight, based on 100 parts by weight of the rubber component in the rubber composition.

[0128] Furthermore, in addition to the above components, the rubber composition may contain required amounts of compounding agents such as crosslinking accelerators, crosslinking activators, antioxidants, activators, process oils, plasticizers, lubricants, etc. in accordance with conventional methods.

[0129] When sulfur or a sulfur-containing compound is used as the crosslinking agent, it is preferable to use a crosslinking accelerator and a crosslinking activator in combination. Examples of the crosslinking accelerator include sulfenamide crosslinking accelerators, guanidine crosslinking accelerators, thiourea crosslinking accelerators, thiazole crosslinking accelerators, thiuram crosslinking accelerators, dithiocarbamic acid crosslinking accelerators, and xanthogenic acid crosslinking accelerators. Among these, those containing sulfenamide crosslinking accelerators are preferable. These crosslinking accelerators are used alone or in combination of two or more. The amount of the crosslinking accelerator is preferably 0.1 to 15 parts by weight, more preferably 0.5 to 5 parts by weight, and particularly preferably 1 to 4 parts by weight, based on 100 parts by weight of the rubber component in the rubber composition.

[0130] Examples of the crosslinking activator include higher fatty acids such as stearic acid, zinc oxide, etc. These crosslinking activators may be used alone or in combination of two or more. The amount of the crosslinking activator is preferably 0.05 to 20 parts by weight, particularly preferably 0.5 to 15 parts by weight, based on 100 parts by weight of the rubber component in the rubber composition.

[0131] In addition, the rubber composition of the present invention may contain a resin in addition to the rubber component. By compounding a resin, it is possible to impart adhesion to the rubber composition or to increase the dispersibility of the filler in the rubber composition. As a result, it is expected that the wet grip property and abrasion resistance of the obtained crosslinked rubber product will be improved. In addition, as an effect similar to that of a plasticizer, it is also possible to improve the processability of the rubber composition. Examples of resins include C5 petroleum resins, C5 / C9 petroleum resins, C9 petroleum resins, dicyclopentadiene resins, terpene resins, terpene phenol resins, aromatic modified terpene resins, alkylphenol-acetylene resins, rosin resins, rosin ester resins, indene resins, C9 resins containing indene, α-methylstyrene-indene copolymer resins, coumarone-indene resins, farnesene resins, and polylimonene resins. These resins may be modified or hydrogenated. These resins may be used alone or in combination of two or more. The amount of the resin to be mixed is preferably 25 parts by weight or less based on 100 parts by weight of the rubber component in the rubber composition.

[0132] To obtain the rubber composition of the present invention, each component may be kneaded according to a conventional method. For example, the compounding ingredients excluding heat-unstable ingredients such as crosslinking agents and crosslinking accelerators are kneaded with the rubber component containing the conjugated diene polymer obtained by the manufacturing method of the present invention, and then the kneaded mixture is mixed with heat-unstable ingredients such as crosslinking agents and crosslinking accelerators to obtain the desired composition. The kneading temperature of the compounding ingredients excluding heat-unstable ingredients and the rubber component containing the conjugated diene polymer obtained by the manufacturing method of the present invention is preferably 80 to 200°C, more preferably 120 to 180°C, and the kneading time is preferably 30 seconds to 30 minutes. In addition, the kneaded mixture is mixed with the heat-unstable ingredients after cooling to usually 100°C or less, preferably 80°C or less.

[0133] <Rubber cross-linked products> The cross-linked rubber product of the present invention is obtained by cross-linking (vulcanizing) the above-mentioned rubber composition of the present invention. The cross-linked rubber product can be produced by using the rubber composition of the present invention, for example, molding the rubber composition into a desired shape using a molding machine such as an extruder, an injection molding machine, a compressor, or a roll, and heating to cause a cross-linking reaction and fix the shape as a cross-linked product. In this case, cross-linking may be performed after molding in advance or simultaneously with molding. The molding temperature is usually 10 to 200°C, preferably 25 to 120°C. The cross-linking temperature is usually 100 to 200°C, preferably 130 to 190°C, and the cross-linking time is usually 1 minute to 24 hours, preferably 2 minutes to 12 hours, and particularly preferably 3 minutes to 6 hours.

[0134] Depending on the shape, size, etc. of the cross-linked rubber product, even if the surface is cross-linked, the inside may not be sufficiently cross-linked, so secondary cross-linking may be performed by further heating.

[0135] The heating method may be appropriately selected from among methods commonly used for crosslinking rubber, such as press heating, steam heating, oven heating, and hot air heating.

[0136] The cross-linked rubber product of the present invention thus obtained is obtained using the conjugated diene polymer obtained by the above-mentioned production method of the present invention, and therefore has excellent low heat generation properties and wet grip properties, and can be suitably used for tires. In particular, the cross-linked rubber product can be used for various applications such as materials for various tire parts such as cap tread, base tread, carcass, sidewall, and bead parts in tires, materials for hoses, belts, mats, anti-vibration rubber, and various other industrial products, impact resistance improvers for resins, resin film buffers, shoe soles, rubber shoes, golf balls, and toys, making use of such properties. In particular, the cross-linked rubber product of the present invention can be suitably used for various tire parts such as tread, carcass, sidewall, and bead parts in various tires such as all-season tires, high-performance tires, and studless tires, and is particularly suitable for use in the tread of low fuel consumption tires, since it has excellent low heat generation properties.

Example

[0137] The present invention will be described in more detail with reference to the following examples. However, the present invention is not limited to the following examples as long as the gist of the present invention is not exceeded.

[0138] <Ethanol Component Evaluation Method> In the following examples and comparative examples, the contents of iron and Si in ethanol were measured using an inductively coupled plasma mass spectrometer (ICP-MS) ELAN DRCII manufactured by PerkinElmer. The content of aromatic compounds in ethanol was measured using a gas chromatography apparatus (GC-2014, manufactured by SHIMADZU).

[0139] <1,3-Butadiene Quantification Method> The quantitative evaluation of 1,3-butadiene was performed by analysis using a gas chromatography apparatus (GC-2014, manufactured by SHIMADZU). The measurement conditions were as follows. <Analysis Conditions of GC / MS Method> Column: Rt-Q-BOND (length 30 m, inner diameter 0.32 mm, film thickness 10 μm) Oven temperature: 60°C for 11.5 minutes → 10°C / minute → 100°C for 14.5 minutes → 10°C / minute → 250°C Sampling time: 5 minutes Carrier gas: He (30 cm / s) Split ratio: 75

[0140] [Reference Example 1] <Preparation of Ethanol> Ethanol was produced as follows. (Raw Material Gas Generation Step) The gas discharged after burning general waste in a waste incineration facility was used. The components of the raw material gas were approximately 30% by volume of carbon monoxide, approximately 30% by volume of carbon dioxide, approximately 30% by volume of hydrogen, and approximately 10% by volume of nitrogen.

[0141] (Synthetic gas refining process) The raw material gas produced as described above was heated to 80°C using a PSA apparatus, which is an impurity removal device, and the carbon dioxide contained in the synthesis gas was removed so that the carbon dioxide content was 60 to 80% by volume of the original content (approximately 30% by volume).The gas was then heated in a double-pipe heat exchanger using steam at 150°C and re-cooled using a double-pipe heat exchanger using cooling water at 25°C to precipitate impurities, which were then removed using a filter, thereby producing a synthesis gas.

[0142] (Microbial fermentation process) The synthesis gas obtained as described above was continuously supplied to a continuous fermentation apparatus (microbial fermentation tank) equipped with a main reactor, synthesis gas supply port, and discharge port, and filled with a seed culture of Clostridium autoethanogenum (a microorganism) and a liquid medium for bacterial culture (containing appropriate amounts of phosphorus compounds, nitrogen compounds, various minerals, etc.), and the culture (microbial fermentation) was carried out continuously for 300 hours. After that, about 8000 L of the culture liquid containing ethanol was extracted from the discharge port.

[0143] (separation process) The culture liquid obtained in the above fermentation step was subjected to a solid-liquid separation filter device under conditions of a culture liquid introduction pressure of 200 kPa or more to obtain an ethanol-containing liquid.

[0144] (Distillation process) The ethanol-containing liquid was then introduced into a distillation apparatus equipped with a heater using steam at 170°C. After the temperature of the bottom of the distillation column was raised to 101°C within 8 to 15 minutes, the ethanol-containing liquid was introduced from the middle of the distillation column, and during continuous operation, the column bottom was kept at 101°C, the middle at 99°C, and the top at 91°C, and the temperature was continuously increased at 15 seconds / L to obtain purified ethanol. The iron content in the obtained ethanol was 0.1 mg / L, and the Si content was 50 mg / L. The toluene content in the obtained ethanol was 0.07 mg / L, the ethylbenzene content was 0.8 mg / L, and the total content of m-xylene and p-xylene was 0.2 mg / L.

[0145] The n-hexane content in the obtained ethanol was 0.1 mg / L, the n-heptane content was 0.04 mg / L, the n-octane content was 0.02 mg / L, the n-decane content was 0.32 mg / L, the n-dodecane content was 0.1 mg / L, and the tetradecane content was 0.03 mg / L. The dibutyl ether content in the obtained ethanol was 20 mg / L.

[0146] (Production method of 1,3-butadiene) 1,3-butadiene was produced using the ethanol obtained as described above. First, the obtained ethanol was vaporized through a single tube heated to 90°C to prepare a gas to be used in the reaction, and the vaporized ethanol gas was merged with nitrogen. The flow rate of the ethanol gas was controlled by mass flow so that the SV of the ethanol gas was 360 L / hr / L and the SV of the nitrogen was 840 L / hr / L, thereby producing a mixed gas of 30% by volume (gas equivalent) of ethanol and 70% by volume (gas equivalent). Next, a 1,3-butadiene-containing gas was obtained by continuously supplying the mixed gas to a cylindrical reaction tube made of stainless steel with a diameter of 1 / 2 inch (1.27 cm) and a length of 15.7 inches (40 cm) and filled with 0.85 g of a catalyst for synthesizing 1,3-butadiene, the main components of which were Hf and Zn, while maintaining the temperature at 325°C and the pressure (pressure of the reaction bed) at 0.1 MPa. The 1,3-butadiene content of the obtained 1,3-butadiene-containing gas was quantified using a gas chromatography apparatus GC-2014 (manufactured by Shimadzu Corporation). The results are shown in Table 1.

[0147] [Reference Comparative Example 1] 1,3-butadiene was produced by the same method as in Reference Example 1 using 99-degree ethanol (manufactured by Amakasu Chemical Industry Co., Ltd.), which is fossil fuel-derived ethanol, and the content of 1,3-butadiene was quantified in the same manner as in Reference Example 1. The results are shown in Table 1. The iron content in the 99-degree ethanol, which is fossil fuel-derived ethanol, was 2.8 mg / L, and the Si content was unmeasurable (below the detection limit, less than 10 mg / L). The toluene content in the obtained ethanol was unmeasurable (below the detection limit, less than 0.01 mg / L), the ethylbenzene content was unmeasurable (below the detection limit, less than 0.1 mg / L), and the total content of m-xylene and p-xylene was unmeasurable (below the detection limit, less than 0.2 mg / L).

[0148] [Reference Comparative Example 2] 1,3-butadiene was produced by the same method as in Reference Example 1 using 99-degree ethanol (manufactured by Amakasu Chemical Industry Co., Ltd.) derived from saccharification and fermentation of plants, and the content of 1,3-butadiene was quantified in the same manner as in Reference Example 1. The results are shown in Table 1. The iron content in the 99-degree ethanol derived from saccharification and fermentation of plants was below the detection limit (less than 0.0001 mg / L), and the Si content was not measurable (below the detection limit, less than 10 mg / L). The toluene content in the obtained ethanol was not measurable (below the detection limit, less than 0.01 mg / L), the ethylbenzene content was not measurable (below the detection limit, less than 0.1 mg / L), and the total content of m-xylene and p-xylene was not measurable (below the detection limit, less than 0.2 mg / L).

[0149] [Table 1]

[0150] As shown in Table 1, ethanol produced from the gas emitted after incinerating general waste in a waste incineration facility has a higher conversion efficiency to 1,3-butadiene than ethanol derived from conventional fossil fuels or ethanol derived from saccharification and fermentation of plants.

[0151] (SBR evaluation method) The styrene butadiene rubber (SBR) synthesized below was evaluated by the following methods. Average molecular weight and dispersity The number average molecular weight (Mn) and weight average molecular weight (Mw) were determined by GPC measurement using a Shodex GPC KF-806L (Showa Denko) column on an HLC-8420GPC (Tosoh). A solution with a sample concentration of 0.2 w / v% was prepared using THF as the eluent and polystyrene as the standard substance. 100 μL of the prepared sample was injected at a flow rate of 1.0 mL / min. The column temperature was 40°C. The degree of dispersion was calculated as Mw / Mn. Glass transition temperature (Tg) Using a thermal analyzer EXSTAR DSC7020 (manufactured by Hitachi High-Tech Science), the glass transition temperature was measured in a temperature range of −100 to 100° C., at a heating rate of 20° C. / min, and in a nitrogen atmosphere.

[0152] [Example 1] (Synthesis of SBR) 1,3-butadiene (iron content in raw material ethanol: 0.1 mg / L) produced in Reference Example 1 was cooled to 10 degrees as a gas and subjected to gas-liquid separation to obtain purified butadiene. At this time, the purity of butadiene was 70%, butadiene / oxygen-containing compound=3.6, and butadiene / hydrocarbon compound=6.2. After adding 129 g of water to a 1 L pressure-resistant reaction vessel, 3 L of nitrogen gas was bubbled (about 50 mL / min x 1 hour). Next, 11.6 g of a 25% potassium rosinate aqueous solution, 0.097 g of potassium oleate, 0.52 g of sodium phosphate, 0.097 g of Rongalite, 0.13 g of paramenthane hydroperoxide, and 16.2 g of styrene were added. The reaction vessel was immersed in a water bath cooled to 5 ° C., and 48.4 g of purified butadiene was added while stirring. Then, 0.032 g of ferric sulfate and 0.045 g of EDTA-4Na were added as initiators. After 20 hours, 0.13 g of N,N'-dimethyldithiocarbamate was added to terminate the reaction, and a latex (styrene-butadiene rubber) was obtained.

[0153] A few drops of sulfuric acid were added to the obtained latex and stirred in water. After filtering the water, the latex was washed with water until the washings became neutral, and then dissolved in THF. The solution was washed with methanol and dried under reduced pressure to obtain a solid rubber (emulsion polymerized SBR). The yield was 44%. Analysis showed that the obtained polymer had an Mn of 91,800, an Mw of 492,000, and an Mw / Mn of 5.36. The glass transition temperature was -46.5.

[0154] [Comparative Example 1] A solid rubber (emulsion-polymerized SBR) was obtained in the same manner as in Example 1, except that the 1,3-butadiene produced in Reference Comparative Example 1 (iron content in raw material ethanol: less than 2.8 mg / L) was used as the 1,3-butadiene. The yield was 29%. Analysis showed that the Mn of the obtained polymer was 82,400, the Mw was 382,000, and the Mw / Mn was 4.64. The glass transition temperature was -40.3.

[0155] [Comparative Example 2] A solid rubber (emulsion-polymerized SBR) was obtained in the same manner as in Example 4, except that the 1,3-butadiene produced in Reference Comparative Example 2 (iron content in raw material ethanol: below the detection limit (less than 0.0001 mg / L)) was used as the 1,3-butadiene. The yield was 43%. Analysis showed that the Mn of the obtained polymer was 67,200, Mw was 297,000, and Mw / Mn was 4.42. The glass transition temperature was -47.1°C.

[0156] (Iron-containing effect) It can be seen from the examples and comparative examples that when the iron content of ethanol is in the range of 0.0001 to 2 mg / L, the Mw / Mn is in the range of 4.7 to 6.0. When iron is present in the range of 0.0001 to 2 mg / L in ethanol, it can adsorb a small amount of oxygen mixed in, preventing a polymerization reaction that proceeds as a side reaction during butadiene synthesis, and improving the selectivity of butadiene. By using high-purity butadiene, the ratio of styrene and butadiene can be precisely controlled, and Mw / Mn can be in the range of 4.7 to 6.0. When iron is present in ethanol at 2 mg / L or more, the amount of butane mixed in the butadiene gas produced during the butadiene synthesis reaction increases. It is believed that the presence of butane that does not act on the polymerization reaction during emulsion polymerization reduces the butadiene ratio in the polymer and increases the Mw / M value.

[0157] It can be seen from the Examples and Comparative Examples that when the iron content of ethanol is in the range of 0.0001 to 2 mg / L, the polymerization yield is high. When iron is present in the range of 0.0001 to 2 mg / L in ethanol, it can adsorb trace amounts of oxygen mixed in, preventing catalyst deactivation due to oxygen during emulsion polymerization, and it is believed that the polymerization yield is high. On the other hand, when ethanol contains iron at 2 mg / L or more, the amount of butane mixed in the butadiene gas produced during the butadiene synthesis reaction increases. It is believed that the presence of butane that does not act on the polymerization reaction during emulsion polymerization reduces the butadiene ratio in the polymer, resulting in a low polymerization yield.

[0158] It can be seen from the examples and comparative examples that when the iron content of ethanol is in the range of 0.0001 to 2 mg / L, the glass transition temperature falls within the range of -41 to -47°C. When ethanol contains iron, the amount of ethyl acetate mixed into the butadiene gas produced during the butadiene synthesis reaction increases. It is believed that the presence of ethyl acetate during emulsion polymerization causes some ethyl acetate to be incorporated into the rubber, lowering the crystallinity of the molecules and lowering the glass transition temperature. On the other hand, when ethanol contains iron at 2 mg / L or more, the amount of ethyl acetate mixed into the butadiene gas produced during the butadiene synthesis reaction increases too much, causing the glass transition temperature to become too high.

Claims

1. A method for producing a non-petroleum-derived conjugated diene-based polymer using a non-petroleum-derived alcohol as a raw material, comprising: A method for producing an alcohol having a carbon number of C by contacting a non-petroleum-derived alcohol having an iron content of 0.001 mg / L or more and 2 mg / L or less and a silicon content of 10 mg / L or more and 100 mg / L or less with a catalyst and heating the alcohol. ４ ~C １２ and producing a conjugated diene, a step of polymerizing the monomer containing the conjugated diene to produce a non-petroleum-derived conjugated diene-based polymer; A method comprising:

2. A method for producing a non-petroleum-derived conjugated diene polymer using a non-petroleum-derived alcohol as a raw material, comprising: a step of producing a conjugated diene having a carbon number of C4 to C12 by contacting an alcohol derived from a non-petroleum raw material, the alcohol having an iron content of 0.001 mg / L or more and 2 mg / L or less and an aromatic compound content of 0.4 mg / L or more and 10 mg / L or less, with a catalyst and heating the alcohol; a step of polymerizing the monomer containing the conjugated diene to produce a non-petroleum-derived conjugated diene-based polymer; A method comprising:

3. The method described in claim 1, wherein the silicon content is 30 mg / L or more and 80 mg / L or less.

4. The method described in claim 2, wherein the content of the aromatic compounds is 0.5 mg / L or more and 7 mg / L or less.

5. A method according to any one of claims 1 to 4, wherein the iron content is 0.01 mg / L or more and 1.0 mg / L or less.

6. The method according to any one of claims 1 to 5, wherein the alcohol derived from non-petroleum-derived raw materials comprises ethanol.

7. The method according to claim 1, wherein the heating temperature is 200 to 450°C.

8. The method according to claim 1, wherein the conjugated diene comprises at least one selected from the group consisting of 1,3-butadiene, isoprene, 1,3-pentadiene, 2,3-dimethyl-1,3-butadiene, 2-methyl-1,3-pentadiene, 1,3-hexadiene, 4,5-diethyl-1,3-octadiene, and 3-butyl-1,3-octadiene.

9. The method according to any one of claims 1 to 8, further comprising polymerizing, as the monomer, at least one aromatic hydrocarbon selected from the group consisting of styrene, methylstyrene, ethylstyrene, t-butylstyrene, α-methylstyrene, α-methyl-p-methylstyrene, chlorostyrene, bromostyrene, methoxystyrene, dimethylaminomethylstyrene, dimethylaminoethylstyrene, diethylaminomethylstyrene, diethylaminoethylstyrene, cyanoethylstyrene, and vinylnaphthalene.

10. The method according to claim 1, wherein the conjugated diene polymer comprises at least one selected from the group consisting of isoprene rubber, butadiene rubber, styrene butadiene rubber, chloroprene rubber, and acrylonitrile butadiene rubber.

11. The method according to claim 1, wherein the conjugated diene polymer has a molecular weight distribution, expressed as a ratio (Mw / Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn), of 4.0 to 6.

0.

12. The method according to claim 1, wherein the conjugated diene polymer has a glass transition temperature (Tg) of -40°C to -50°C.

13. A method for producing a cross-linked rubber product, comprising the steps of: A method comprising a step of kneading the non-petroleum-derived conjugated diene-based polymer obtained by the method according to any one of claims 1 to 12 as a rubber component with a filler, and crosslinking the mixture.

14. A method for manufacturing a tire, using a cross-linked rubber product obtained by the method according to claim 13.