Method for producing (POLY)alkylene glycol monoalkyl ether

Abstract

A (poly)alkylene glycol monoalkyl ether is produced at high selectivity and high yield from an olefin and a (poly)alkylene glycol. The present invention provides a method for producing a (poly)alkylene glycol monoalkyl ether in which an olefin and a (poly)alkylene glycol are reacted, using a crystalline metallosilicate as a catalyst, in the presence of a solvent to form a solution having a homogenous liquid phase; the solution is then separated after the reaction at a temperature lower than the reaction temperature into an upper layer containing mainly the olefin and (poly)alkylene glycol monoalkyl ether and a lower layer containing mainly the solvent and (poly)alkylene glycol; and the (poly)alkylene glycol monoalkyl ether is then obtained from the upper layer.

Description

Method for producing (poly)alkylene glycol monoalkyl ether

[0001] The present invention relates to a method for producing a (poly)alkylene glycol monoalkyl ether. More specifically, the present invention relates to a method for producing a (poly)alkylene glycol monoalkyl ether by reacting an olefin with a (poly)alkylene glycol.

[0002] The following methods have been proposed as methods for producing (poly)alkylene glycol monoalkyl ethers by reacting an olefin with a (poly)alkylene glycol.

[0003] Japanese Patent Publication No. 2703752 (equivalent to U.S. Pat. No. 5,741,948 A) discloses the reaction of an olefin with a (poly)alkylene glycol using a BEA-type metallosilicate catalyst to obtain a (poly)alkylene glycol monoalkyl ether. It explains that the reaction can be carried out in the presence or absence of a solvent, and that solvents that can be used include nitromethane, nitroethane, nitrobenzene, dioxane, ethylene glycol dimethyl ether, sulfolane, benzene, toluene, xylene, hexane, cyclohexane, decane, and paraffin. International Publication No. 2021 / 067223 (equivalent to U.S. Pat. No. 2022 / 0274903 A1) also explains that the reaction of an olefin with a (poly)alkylene glycol using a BEA-type metallosilicate catalyst in the presence of a solvent such as ethylene glycol dimethyl ether or diethylene glycol dimethyl ether increases the selectivity of the monoalkyl ether to 85% or more.

[0004] However, in the reaction using such a solvent, after the reaction in a homogeneous solution, when the solvent, unreacted olefin, (poly)alkylene glycol, and other reaction impurities are removed to obtain a (poly)alkylene glycol monoalkyl ether, a large amount of liquid must be distilled off by distillation, which is energy-disadvantageous in terms of distillation of the reaction solution. Furthermore, there are problems such as the distillation becoming unstable due to changes in the solution composition in the bottoms during distillation, resulting in phase separation, causing bumping, unstable vapor composition, resulting in a decrease in the yield of the (poly)alkylene glycol monoalkyl ether, and difficulty in controlling the degree of purification.

[0005] As a result of intensive research conducted by the present inventors to solve these problems, they have discovered an efficient method for producing a (poly)alkylene glycol monoalkyl ether, which makes use of the advantages of reaction using a solvent, and by lowering the temperature of the reaction solution after the reaction to a temperature lower than the reaction temperature and separating it into an upper layer (A) containing mainly olefins and (poly)alkylene glycol monoalkyl ether, and a lower layer (B) containing mainly (poly)alkylene glycol, dramatically reducing the total amount of upper layer (A) containing the product (poly)alkylene glycol monoalkyl ether, and enabling stable distillation to yield a highly pure product.

[0006] That is, the present invention encompasses the following: (1) A method for producing a (poly)alkylene glycol monoalkyl ether, comprising: a reaction step in which an olefin and a (poly)alkylene glycol are reacted as a homogeneous liquid solution in the presence of a solvent at 110 to 250°C using a crystalline metallosilicate as a catalyst; a separation step in which the reaction solution obtained in the reaction step is separated into an upper layer (A) and a lower layer (B) at a temperature lower than 110°C; and a step in which the upper layer (A) separated in the separation step is distilled to obtain the (poly)alkylene glycol monoalkyl ether. (2) The production method according to (1), further comprising the steps of distilling the solvent component from the lower layer (B) separated in the separation step, separating the mixture into an upper layer (C) and a lower layer (D), and obtaining the (poly)alkylene glycol monoalkyl ether from the separated upper layer (C) by distillation. (3) The production method according to (1) or (2), wherein the olefin is at least one selected from the group consisting of acyclic olefins having 6 to 30 carbon atoms. (4) The production method according to any one of (1) to (3), wherein the crystalline metallosilicate is a pentasil-type metallosilicate or a BEA-type metallosilicate. (5) The production method according to any one of (1) to (4), wherein the solvent used in the reaction has a solubility parameter in the range of 16 to 20 and is a compound represented by the following formula (I):

[0007]

[0008] In the above formula (I), R １ is a linear or branched alkyl group having 1 to 4 carbon atoms; R ２ is a linear or branched alkyl group having 1 to 4 carbon atoms or an acetyl group, A is a linear or branched alkylene group having 2 to 4 carbon atoms, and n is an integer of 1 to 4. (6) A method for producing a higher secondary alcohol alkoxylate adduct, comprising further adding an alkylene oxide to the (poly)alkylene glycol monoalkyl ether obtained by any one of (1) to (5).

[0009] Hereinafter, embodiments of the present invention will be described. Note that the present invention is not limited to the following embodiments, and various modifications can be made within the scope of the claims. Furthermore, the embodiments described in this specification can be arbitrarily combined to form other embodiments.

[0010] Throughout this specification, singular expressions should be understood to include the plural concept unless otherwise specified. Therefore, singular articles (e.g., "a," "an," "the," etc. in English) should be understood to include the plural concept unless otherwise specified. Furthermore, terms used in this specification should be understood to be used in the sense commonly used in the art unless otherwise specified. Therefore, unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. In case of conflict, the present specification (including definitions) will prevail.

[0011] In this specification, the range "X to Y" is inclusive of X and Y and means "X or more and Y or less." Unless otherwise specified, measurements of operations and physical properties are performed at room temperature (20°C or more and 25°C or less) and at a relative humidity of 40% RH or more and 50% RH or less.

[0012] One aspect of the present invention relates to a method for producing a (poly)alkylene glycol monoalkyl ether, comprising: a reaction step (reaction step) using a crystalline metallosilicate as a catalyst to react an olefin and a (poly)alkylene glycol in the presence of a solvent at 110 to 250°C to form a homogeneous liquid solution; a separation step (separation step) of separating the reaction solution obtained in the reaction step into an upper layer (A) and a lower layer (B) at a temperature lower than 110°C; and a purification step (purification step) of obtaining a (poly)alkylene glycol monoalkyl ether by distillation from the upper layer (A) separated in the separation step. According to the present invention, since the solvent is removed in the separation step, the amount of solvent distilled off (distillative separation) when recovering the reaction product can be reduced, which is advantageous from an energy perspective. Furthermore, according to the present invention, a (poly)alkylene glycol monoalkyl ether can be produced in high yield by reacting an olefin and a (poly)alkylene glycol in the presence of a catalyst with high selectivity. According to the present invention, a (poly)alkylene glycol monoalkyl ether can be produced from an olefin and a (poly)alkylene glycol with high selectivity and high yield. Also, according to the present invention, a high-purity (poly)alkylene glycol monoalkyl ether can be produced.

[0013] [Reaction Step] In this step, an olefin is reacted with a (poly)alkylene glycol in the presence of a crystalline metallosilicate (catalyst) at a temperature of 110 to 250°C using a solvent that forms a homogeneous liquid phase. Conventionally, raw olefins are not compatible with (poly)alkylene glycols (e.g., ethylene glycol), and therefore easily separate into two layers after the reaction. Therefore, the olefin phase containing the reaction product ((poly)alkylene glycol monoalkyl ether) is easily separated, allowing the (poly)alkylene glycol and catalyst to be recovered. However, due to the ease of separation, the reaction must be carried out under vigorous stirring. Furthermore, as mentioned above, it is known to use a solvent in the reaction to promote the reaction, but this requires solvent distillation (distillation separation) to recover the reaction product, which is energy-inefficient. In contrast, according to the present invention, the reaction can be carried out in a homogeneous solution state, and therefore does not require vigorous stirring. Furthermore, when the temperature is lowered, phase separation easily occurs into an upper layer mainly containing the reaction product ((poly)alkylene glycol monoalkyl ether), unreacted olefin, and solvent, and a lower layer mainly containing the solvent and unreacted (poly)alkylene glycol, which allows the reaction product to be easily and reliably recovered (in high yield / high yield).

[0014] In this specification, the term "a solution having a uniform liquid phase" means that the liquid phase is a single phase. Specifically, whether the liquid phase is a uniform solution is evaluated by visually checking whether the liquid phase is separated into two layers. If the liquid phase is not separated into two layers and is a single phase, the liquid phase is evaluated as being a uniform solution.

[0015] The olefin used in the present invention is a hydrocarbon having 2 to 40 carbon atoms and an ethylenically unsaturated bond, preferably an acyclic hydrocarbon having 6 to 30 carbon atoms and an ethylenically unsaturated bond, more preferably an acyclic hydrocarbon having 8 to 20 carbon atoms and one ethylenically unsaturated bond, and particularly preferably an acyclic hydrocarbon (acyclic olefin) having 12 to 16 carbon atoms and one ethylenically unsaturated bond (dodecene, tridecene, tetradecene, pentadecene, hexadecene). Specific examples include ethylene, propylene, butene, isobutylene, butadiene, pentene, hexene, octene, nonene, decene, undecene, dodecene, tridecene, tetradecene, pentadecene, hexadecene, heptadecene, octadecene, nonadecene, eicosene, henicosene, docosene, tricosene, and tetracosene. These may be used alone or in a mixture of two or more. In particular, olefins having a large number of carbon atoms, such as octene, decene, dodecene, tetradecene, hexadecene, octadecene, and eicosene, are preferably used. These olefins can be used without particular limitation, regardless of whether the unsaturated bond is in the α-position, the inner position, or both the α- and inner positions. In one embodiment of the present invention, the olefin has an unsaturated bond in the α-position (e.g., 1-dodecene, 1-tridecene, and 1-tetradecene). In one embodiment of the present invention, the olefin has an unsaturated bond in the inner position (e.g., inner dodecene, inner tridecene, and inner tetradecene). Of course, two or more of these olefins having different unsaturated bond positions can also be used in combination. In one embodiment of the present invention, the olefin is a mixture of an olefin having an unsaturated bond in the α-position and an olefin having an unsaturated bond in the inner position (e.g., a mixture of 1-dodecene and inner dodecene, a mixture of 1-tridecene and inner tridecene, and a mixture of 1-tetradecene and inner tetradecene). In the reaction process of the present invention, a reaction of isomerizing the position of the unsaturated bond of an olefin occurs simultaneously. Generally, inner olefins are thermodynamically more stable than α-olefins, so when an α-olefin is used as a raw material, the olefin gradually isomerizes to the inner olefin during the reaction.The rate of isomerization varies depending on the reaction temperature and the type and amount of crystalline metallosilicate used as a catalyst. (Poly)alkylene glycol monoalkyl ethers obtained from these acyclic olefins having 6 to 30 carbon atoms are suitable as raw materials for surfactants.

[0016] Examples of the (poly)alkylene glycol used in the present invention include monoethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, monopropylene glycol, dipropylene glycol, tripropylene glycol, polypropylene glycol, 1,3-propanediol, 1,2-butanediol, 2,3-butanediol, 1,4-butanediol, 1,6-hexanediol, paraxylylene glycol, and 1,4-cyclohexanemethanediol. These may be used alone or in a mixture of two or more. Of these, monoethylene glycol, diethylene glycol, triethylene glycol, and monopropylene glycol are preferred, with monoethylene glycol being more preferred. According to one embodiment of the present invention, the number of carbon atoms in the alkylene group in the (poly)alkylene glycol is 1 to 8, 1 to 6, 1 to 4, or 1 to 3. According to one embodiment of the present invention, the number of moles of alkylene oxide added in the (poly)alkylene glycol may be 1 to 20.

[0017] The crystalline metallosilicate used in the present invention is an ordered porous substance having a certain crystal structure, i.e., it is a solid substance having a large specific surface area and a large number of ordered voids or holes within its structure.

[0018] The crystalline metallosilicates used in the present invention are crystalline aluminosilicates (commonly known as zeolites) and compounds in which other metal elements have been introduced into the crystal lattice in place of the Al atoms of the crystalline aluminosilicates. Specific examples of such other metal atoms include at least one of B, Ga, In, Ge, Sn, P, As, Sb, Sc, Y, La, Ti, Zr, V, Cr, Mn, Fe, Co, Ni, Cu, and Zn. In terms of catalytic activity and ease of synthesis and availability, crystalline aluminosilicates, crystalline ferrosilicates, crystalline borosilicates, and crystalline gallosilicates are preferred, with crystalline aluminosilicates being more preferred.

[0019] According to one embodiment of the present invention, the specific surface area of ​​the catalyst is 400 to 800 m ２ / g.

[0020] Specific examples of the crystalline metallosilicates used in the present invention, when described using the IUPAC code, include those having structures such as MFI (ZSM-5, etc.), MEL (ZSM-11, etc.), BEA (β-type zeolite, etc.), FAU (Y-type zeolite, etc.), MOR (mordenite, etc.), MTW (ZSM-12, etc.), and LTL (L-type zeolite, etc.). In addition to these, those having structures described in "ZEOLITES, Vol. 12, No. 5, 1992" and "HANDBOOK OF MOLECULAR SIEVEES," written by R. Szostak, published by Van Nostrand Reinhold, etc., can also be mentioned. These may be used alone or in combination of two or more types. Among these, those having a structure such as MFI or MEL, which are called pentasil types, or a BEA structure are preferred because of their excellent catalytic activity. That is, in a preferred embodiment of the present invention, the crystalline metallosilicate is a pentasil type metallosilicate or a BEA type metallosilicate.

[0021] The crystalline metallosilicate used in the present invention preferably has an atomic ratio of silicon atoms to metal atoms constituting it in the range of 5 to 1500, particularly 10 to 500. Crystalline metallosilicates in which the atomic ratio of silicon atoms to metal atoms is too small or too large are not preferred because they have low catalytic activity.

[0022] Many of these crystalline metallosilicates have exchangeable cations outside the crystal lattice. Specific examples of these cations include H ＋ , Li ＋ , Na ＋ , Rb ＋ , Cs ＋ , Mg ２＋ , Ca ２＋ , Sr ２＋ , Ba ２＋ , Sc ３＋ , Y ３＋ , La ３＋ , R ４ N ＋ , R ４ P ＋ , (R is H or an alkyl group). Among them, the cations may be wholly or partially replaced with hydrogen ions (H ＋ ) are preferred catalysts of the present invention.

[0023] The crystalline metallosilicates used in the present invention can be synthesized by commonly used synthesis methods, such as hydrothermal synthesis. Specifically, they can be synthesized by methods described in Japanese Patent Publication No. 46-10064, U.S. Patent No. 3,965,207, and Journal of Molecular Catalysis, Vol. 31, pp. 355-370 (1985), among others. These crystalline metallosilicates can be synthesized, for example, by heating a composition consisting of a silica source, a metallo source, and a quaternary ammonium salt such as tetrapropylammonium salt at a temperature of approximately 100 to 175°C until crystals are formed, filtering the solid product, washing with water, drying, and then calcining at 350 to 600°C. Examples of silica sources that can be used include water glass, silica sol, silica gel, and alkoxysilane. Various inorganic or organic metal compounds can be used as the metallo source. Suitable examples of such metal compounds include metal sulfates [e.g., Al ２ (SO ４ ) ３ ], metal nitrates [e.g., Fe(NO ２ ) ２], alkali metal salts of metal oxides [e.g., NaAlO ２ metal salts such as chlorides of metals [e.g., TiCl ４ ], metal bromides [e.g., MgBr ２ metal halides such as Ti(OC) ２ H ５ ) ４ The resulting crystalline metallosilicate can be ion-exchanged to the desired cation form, if necessary. For example, H + The cationic form of the crystalline metallosilicate is HCl, NH ４ Cl, NH ３ The cationic species are mixed and stirred in an aqueous solution of H ＋ Type or NH ４ ＋ The solid product is then filtered, washed with water, dried, and calcined at 350 to 600°C. ＋ Cationic forms other than those listed above can be prepared by carrying out the same procedure using an aqueous solution containing the desired cation.

[0024] Alternatively, the crystalline metallosilicate used in the present invention may be a commercially available product, such as the HSZ-900 series (BEA), HSZ-800 series (ZSM-5), HSZ-600 series (mordenite), HSZ-500 series (L-type), and HSZ-300 series (Y-type) zeolites (all manufactured by Tosoh Corporation), the CP series, CBV series, and ZD series (all manufactured by Zeolyst International), the CZB series, CZP series, CZM series, CZC series, LiCZF series, CZA series, CZE series, and CZL series (all manufactured by Clariant).

[0025] The crystalline metallosilicate may be calcined before the reaction. Calcination conditions are not particularly limited and can be appropriately selected depending on the desired degree of catalytic activity. The calcination temperature is, for example, 300 to 1000°C, particularly 500 to 700°C. The calcination time is, for example, 1 to 10 hours, particularly 1 to 5 hours. Calcination may be carried out in air or in an inert atmosphere (e.g., nitrogen, argon).

[0026] The catalyst in this reaction may be in any form, such as powder, granules, molded bodies having a specific shape, etc. When a molded body is used, alumina, silica, titania, etc. may be used as a carrier or binder.

[0027] In the present invention, an olefin is reacted with a (poly)alkylene glycol in the presence of a crystalline metallosilicate (catalyst) using a solvent that forms a homogeneous liquid solution. Any solvent that can be used in the reaction may be used as long as it forms a homogeneous liquid solution (allows the reaction to proceed uniformly). The solvent that can be used in the reaction preferably contains a compound represented by formula (I) below, which has a solubility parameter of 16 to 20. More preferably, the solvent that can be used in the reaction is solely a compound represented by formula (I) below, which has a solubility parameter of 16 to 20.

[0028] That is, in the present invention, the reaction between an olefin and a (poly)alkylene glycol is preferably carried out in the presence of a compound represented by the following formula (I) having a solubility parameter in the range of 16 to 20. In a preferred embodiment of the present invention, the solvent used in the reaction has a solubility parameter in the range of 16 to 20 and contains a compound represented by the following formula (I). In a more preferred embodiment of the present invention, the solvent used in the reaction has a solubility parameter in the range of 16 to 20 and is a compound represented by the following formula (I). In a particularly preferred embodiment of the present invention, the solvent used in the reaction has a solubility parameter in the range of 16 to 20 and is one type of compound represented by the following formula (I).

[0029]

[0030] In the above formula (I), R １is a linear or branched alkyl group having 1 to 4 carbon atoms. １ Examples of the alkyl group as R include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, and a tert-butyl group. Among these, from the viewpoint of further uniformity of the liquid phase during the reaction, R １ is preferably a methyl group, an ethyl group, or a butyl group, more preferably a methyl group or an ethyl group, and particularly preferably a methyl group. ２ represents a linear or branched alkyl group having 1 to 4 carbon atoms, or an acetyl group (CH ３ CO-), where R ２ Specific examples of the alkyl group as R １ Among these, from the viewpoint of further uniformity of the liquid phase during the reaction, R ２ is preferably a methyl group, an ethyl group, a butyl group, or an acetyl group, more preferably a methyl group or an ethyl group, and particularly preferably a methyl group. A is a linear or branched alkylene group having 2 to 4 carbon atoms. When a plurality of As are present (n is 2 to 4), each As may be the same or different. Examples of the alkylene group represented by A include an ethylene group (-CH ２ CH ２ -), trimethylene group (-CH ２ CH ２ CH ２ -), propylene group (-CH(CH ３ ) CH ２ - or -CH ２ CH (CH ３ )-), tetramethylene group (-CH ２ CH ２ CH ２ CH ２ Of these, from the viewpoint of achieving a more uniform liquid phase during the reaction, A is preferably an ethylene group or a propylene group, and particularly preferably an ethylene group. n is 1 to 4. From the viewpoint of achieving a more uniform liquid phase during the reaction, m is more preferably 1 to 3, further preferably 1 or 2, and particularly preferably 2.

[0031] The solubility parameter (SP value) of the solvent is 16 to 20. From the viewpoint of further uniformity of the liquid phase during the reaction, the solubility parameter is preferably 16.5 to 19.0, more preferably 17.0 or more and less than 19.0, and particularly preferably 17.5 to 18.5.

[0032] In the present invention, the solubility parameter (SP value) refers to the Hansen solubility parameter, which is an index that serves as a guide for the solubility of a two-component solution. The SP value δ (J / cm ３ The following formula (II) was used to calculate

[0033]

[0034] where δ ｄ is the London dispersion force term, δ ｐ is the molecular polarization term, δ ｈ is called the hydrogen bond term.

[0035] The solubility parameter can be calculated using the Hansen Solubility Parameter software (HSPiP ver. 5.3.08). A mixture of multiple solvents can also be used.

[0036] Specific examples of the solvent include the R １ , R ２ Examples of dialkyl glycol ethers in which R is an alkyl group include ethylene glycol dimethyl ether (SP value = 17.9), diethylene glycol dimethyl ether (SP value = 18.3), triethylene glycol dimethyl ether (SP value = 18.4), ethylene glycol diethyl ether (SP value = 17.1), diethylene glycol diethyl ether (SP value = 17.5), diethylene glycol dibutyl ether (SP value = 17.0), propylene glycol dimethyl ether (SP value = 17.0), and propylene glycol diethyl ether (SP value = 16.6). １ is an alkyl group, R ２Examples of glycol ether acetates in which the acetyl group is present include ethylene glycol monomethyl ether acetate (SP value = 19.3), ethylene glycol monoethyl ether acetate (SP value = 18.6), ethylene glycol monobutyl ether acetate (SP value = 18.0), diethylene glycol monoethyl ether acetate (SP value = 18.6), diethylene glycol monobutyl ether acetate (SP value = 18.1), propylene glycol monomethyl ether acetate (SP value = 18.3), propylene glycol monoethyl ether acetate (SP value = 17.8), and dipropylene glycol monomethyl ether acetate (SP value = 18.3). Particularly preferred solvents include ethylene glycol dimethyl ether and diethylene glycol dimethyl ether. The above solvents may be used alone or in the form of a mixture of two or more, but are preferably used alone.

[0037] The reaction step in the present invention is characterized by using a crystalline metallosilicate as a catalyst and reacting an olefin and a (poly)alkylene glycol in the presence of a solvent at 110 to 250°C as a homogeneous liquid solution. When a solvent is not used, the raw materials (poly)alkylene glycol and olefin are partitioned only to the extent of their mutual solubility, with the crystalline metallosilicate catalyst partitioning into the (poly)alkylene glycol phase and the product (poly)alkylene glycol monoalkyl ether partitioning into the olefin phase, resulting in a very slow reaction rate. However, the use of a solvent results in a homogeneous liquid phase, facilitating contact between the olefin and the catalyst and increasing the reaction rate with the (poly)alkylene glycol. Here, "a homogeneous liquid phase" means that the liquid phase is homogeneous at a reaction temperature of 110°C or higher, or that the liquid phase is homogeneous as the temperature is increased or the reaction progresses (e.g., 120 minutes after the predetermined reaction temperature is reached). The liquid phase does not necessarily have to be homogeneous when the materials are mixed at temperatures below 110°C. The amount of the solvent used to homogenize the liquid phase in this way is preferably 35% by mass or more, more preferably 60% by mass or more, even more preferably 80% by mass or more, and particularly preferably more than 100% by mass, based on the total amount of the olefin, (poly)alkylene glycol, and solvent. The upper limit of the amount of the solvent used is, for example, 300% by mass or less, preferably 250% by mass or less, and more preferably 200% by mass or less, based on the total amount of the olefin, (poly)alkylene glycol, and solvent.

[0038] Alternatively or in addition, the amount of solvent added exceeds 62 parts by mass per 100 parts by mass of olefin. If the amount is below the lower limit, the liquid phase during the reaction separates into two layers and becomes non-uniform. From the viewpoints of further improving the uniformity of the liquid phase (for example, uniformity of the liquid phase from the start of the reaction) and further facilitating separation in the separation step, the solvent is preferably used in the reaction in an amount of 150 to 800 parts by mass, more preferably 165 to 600 parts by mass, even more preferably more than 165 parts by mass but not more than 500 parts by mass, and particularly preferably 250 to 350 parts by mass per 100 parts by mass of olefin.

[0039] The reaction in the present invention can be carried out by a commonly used method such as a batch reaction or a flow reaction, and is not particularly limited. The molar ratio of the olefin and (poly)alkylene glycol, which are the raw materials for the reaction, is not particularly limited. The (poly)alkylene glycol is used in a ratio of, for example, 0.05 to 20 moles, preferably 0.1 to 10 moles, more preferably 1 to 5 moles, per mole of olefin.

[0040] The reaction temperature is 110 to 250°C, preferably 110 to 200°C, more preferably 110 to 170°C, and particularly preferably 120 to 150°C. A high reaction temperature increases the reaction rate but is not preferred because it generates by-products due to side reactions. The reaction pressure may be reduced, normal pressure, or increased pressure, but is preferably in the range of normal pressure to 2 MPa.

[0041] When a batch reactor is used, the reactor is filled with the catalyst of the present invention and raw materials, and the mixture is stirred at a predetermined temperature and pressure to obtain a mixture containing the desired (poly)alkylene glycol monoalkyl ether. The amount (addition amount) of the crystalline metallosilicate (catalyst) used is not particularly limited and is appropriately selected depending on the desired degree of reaction progress, etc. The amount of the crystalline metallosilicate (catalyst) used is 0.1 to 150% by mass, preferably 0.5 to 100% by mass, more preferably 10 to 100% by mass, and particularly preferably 20.0 to 99.5% by mass, based on the olefin raw material.

[0042] The reaction time varies depending on the reaction temperature, the amount of catalyst, the raw material composition ratio, etc., but is in the range of 0.1 to 100 hours, preferably 0.5 to 30 hours, preferably 1 to 10 hours, more preferably 2 to 5 hours.

[0043] [Separation Step] In this step, the reaction liquid obtained in the above reaction step is separated into an upper layer (A) and a lower layer (B) at a temperature lower than 110°C.

[0044] In the separation step of the present invention, in order to obtain a (poly)alkylene glycol monoalkyl ether from the reaction solution obtained in the reaction step, the reaction solution is cooled to a temperature lower than 110°C and allowed to stand, separating into two layers: an upper layer (A) containing mainly the solvent, unreacted olefin, and the product (poly)alkylene glycol monoalkyl ether, and a lower layer (B) containing mainly the solvent and unreacted (poly)alkylene glycol. The temperature for separation (separation temperature) should be lower than 110°C, preferably 100°C or lower, more preferably 90°C or lower, even more preferably 50°C or lower, and particularly preferably less than 40°C. The temperature for separation (separation temperature) should be a temperature that does not freeze, and is, for example, −20°C or higher, preferably 10°C or higher, more preferably 20°C or higher. Alternatively, from the viewpoint of facilitating further separation of the upper layer (A) and the lower layer (B), the difference between the reaction temperature in the above reaction step and the separation temperature in this step is, for example, 10 to 200°C, preferably 30 to 150°C, more preferably 50 to 140°C, even more preferably 70 to 130°C, and particularly preferably greater than 95°C and less than 120°C. Furthermore, separation may be carried out after removing the catalyst by filtration or centrifugation, or may be carried out while the catalyst is still contained. The catalyst separated by methods such as centrifugation or filtration can be used in repeated reactions as is or after being regenerated.

[0045] Thus, the amount of solvent suitable for forming a homogeneous liquid phase during the reaction and separating into two layers after the reaction is preferably 35% by mass or more, more preferably 38% by mass or more, and even more preferably 40% by mass or more, relative to the total of the olefin, (poly)alkylene glycol, and solvent. If the solvent content is less than 35% by mass, the liquid phase of the reaction solution will not be homogeneous at the reaction temperature, slowing the reaction rate, which is undesirable. If the solvent content is more than 65% by mass, the liquid phase of the reaction solution will be homogeneous, but will not separate even if the temperature of the reaction solution is lowered below 110°C, and the amount of reaction solution will increase, resulting in the production of a (poly)alkylene glycol monoalkyl ether. Furthermore, a large amount of distillation energy will be required to recover and reuse unreacted olefin, unreacted (poly)ethylene glycol, solvent, etc. in the reaction, which is undesirable. The solvent content is preferably 65% ​​by mass or less, more preferably 60% by mass or less, and even more preferably 55% by mass or less.

[0046] The method for adjusting the amount of solvent to a level suitable for separation includes adjusting the amount of solvent during reaction preparation or adjusting the amount of solvent by distillation after the reaction. When using a solvent in an amount greater than that suitable for separation, the solvent can be removed by distillation from the reaction solution after the reaction to achieve a solvent amount suitable for separation. That is, the present invention includes a method for adjusting the amount of solvent suitable for separation in the reaction step and then carrying out the reaction, and / or a method for removing the solvent by distillation from the reaction solution after the reaction to achieve a solvent amount suitable for separation. The distillation conditions are not particularly limited, and known methods can be used. For example, the distillation temperature at the top of the distillation column is typically 50 to 300°C. Distillation may be carried out under either atmospheric pressure or reduced pressure, but is preferably carried out under reduced pressure. The preferred degree of reduced pressure is 15 kPa or less, more preferably 10 kPa or less. The preferred degree of reduced pressure is 50 Pa or more, more preferably 100 Pa or more.

[0047] [Purification Step] In this step, a (poly)alkylene glycol monoalkyl ether is obtained by distillation from the upper layer (A) separated in the above separation step.

[0048] The process of obtaining a (poly)alkylene glycol monoalkyl ether by distillation from the upper layer (A) separated in the separation process of the present invention is a process in which, since the upper layer (A) mainly contains the solvent, unreacted olefins, and the product (poly)alkylene glycol monoalkyl ether, low-boiling components such as the solvent and unreacted olefins are distilled off by distillation to obtain a (poly)alkylene glycol monoalkyl ether. The distillation conditions are not particularly limited, and known methods, such as the same methods as those used for distilling the solvent described above, can be used. The obtained (poly)alkylene glycol monoalkyl ether can be used as is or after purification as a raw material for the higher secondary alcohol alkoxylate adduct described below.

[0049] The lower layer (B) contains the catalyst, unreacted (poly)alkylene glycol, solvent, and also some of the target (poly)alkylene glycol monoalkyl ether and unreacted olefin. The lower layer (B) can be reused for the reaction of the (poly)alkylene glycol monoalkyl ether by adding the raw olefin or (poly)alkylene glycol as needed. Alternatively, by removing the solvent component from the lower layer (B) by distillation, the lower layer (B) can be separated into an upper layer (C) mainly containing unreacted olefin and the reaction product (poly)alkylene glycol monoalkyl ether, and a lower layer (D) mainly containing unreacted (poly)alkylene glycol. That is, the present invention may further include a step of removing the solvent from the lower layer (B) by distillation to separate the upper layer (C) and the lower layer (D), and obtaining the (poly)alkylene glycol monoalkyl ether from the separated upper layer (C) by distillation. In this way, a (poly)alkylene glycol monoalkyl ether can be obtained from the lower layer (B), and the (poly)alkylene glycol monoalkyl ether produced in the reaction can be recovered without waste. When the solvent component is removed from the lower layer (B) by distillation, this may be done after the catalyst has been removed by filtration or centrifugation, or it may be done while the catalyst is still contained. The catalyst separated by a method such as centrifugation or filtration can be used for repeated reactions as is or after being regenerated.

[0050] In one embodiment of the present invention, the method of the present invention further comprises the step of distilling off the solvent component from the lower layer (B) separated in the separation step, separating the lower layer (B) into an upper layer (C) and a lower layer (D), and obtaining a (poly)alkylene glycol monoalkyl ether from the separated upper layer (C) by distillation.

[0051] The (poly)alkylene glycol monoalkyl ether is obtained by distillation from the separated upper layers (A) and (C), and the unreacted olefin and solvent are also recovered by distillation and can be reused as reaction raw materials or solvents. The lower layer (D) also contains unreacted (poly)alkylene glycol, which can be reused as reaction raw materials either as is or after purification.

[0052] The distillation conditions are not particularly limited, and known methods can be used. For example, the distillation temperature at the top of the distillation column is usually 50 to 300°C, preferably 70 to 300°C, and more preferably 70 to 250°C. The distillation residence time is usually 24 hours or less, preferably 12 hours or less, and more preferably 6 hours or less. The distillation residence time is preferably 10 minutes or more, more preferably 20 minutes or more, and even more preferably 30 minutes or more. The distillation may be carried out under either atmospheric pressure or reduced pressure, but is preferably carried out under reduced pressure, with the preferred degree of reduced pressure being 15 kPa or less, more preferably 10 kPa or less. The preferred degree of reduced pressure is 50 Pa or more, more preferably 100 Pa or more.

[0053] When a flow reactor is used, any of a fluidized bed type, a fixed bed type, and a stirred tank type can be used. The reaction conditions vary depending on the raw material composition, catalyst concentration, reaction temperature, etc., but the liquid hourly space velocity (LHSV), i.e., the value obtained by dividing the volumetric flow rate of the flowing raw material by the volume of the reactor, is 0.01 to 50 hr -1 Especially 0.1 to 20 hours -1 After the reaction is completed, the target (poly)alkylene glycol monoalkyl ether can be recovered by the same operation as in the batch reaction.

[0054] [Method for producing a higher secondary alcohol alkoxylate adduct] The present invention provides a method for producing a higher secondary alcohol alkoxylate adduct, which comprises further adding an alkylene oxide to the (poly)alkylene glycol monoalkyl ether obtained above in the presence of a catalyst.

[0055] The method for producing the higher secondary alcohol alkoxylate adduct of the present invention is not particularly limited as long as it is a method capable of adding an alkylene oxide to a (poly)alkylene glycol monoalkyl ether, and known methods can be used in the same manner or with appropriate modifications. For example, an alkylene oxide is added to the (poly)alkylene glycol monoalkyl ether obtained by the above method in an appropriate molar ratio, and the reaction is carried out in the presence of an alkali catalyst, an acid catalyst, a solid acid catalyst such as alumina magnesia, a double metal cyanide (DMC) catalyst, or the like. The alkylene oxide may be of only one type, or of two or more types. In the latter case, two or more types of alkylene oxides may be added randomly, each may be added in blocks, or a random structure and a block structure may be combined.

[0056] Examples of the alkylene oxide include ethylene oxide, propylene oxide, butylene oxide, styrene oxide, etc. The molar ratio of alkylene oxide to (poly)alkylene glycol monoalkyl ether is not particularly limited, but is preferably 1 to 30, more preferably 2 to 25, and even more preferably 4 to 20, such as 3 to 18, 4 to 16, or 5 to 12.

[0057] As reaction conditions for adding alkylene oxide to (poly)alkylene glycol monoalkyl ether, the reaction temperature is usually 50 to 250°C, preferably 100 to 200°C, 110 to 180°C, or 120 to 160°C. According to one embodiment of the present invention, the reaction time is 0.5 to 40 hours, 0.5 to 20 hours, or 1 to 10 hours. The reaction pressure may be either atmospheric pressure or elevated pressure, but is preferably in the range of atmospheric pressure to 2 MPa (1 MPa or less, or 0.5 MPa or less). If the reaction temperature is below 50°C, the reaction rate may be slow, while if it exceeds 250°C, decomposition and an increase in by-products may occur, which is not preferable.

[0058] Examples of the alkali catalyst include hydroxides of elements belonging to alkali metals or alkaline earth metals, such as sodium hydroxide, potassium hydroxide, lithium hydroxide, magnesium hydroxide, calcium hydroxide, and barium hydroxide. In view of availability and reactivity, sodium hydroxide and potassium hydroxide are preferred. These may be added in the form of powder, granules, or even as an aqueous solution, followed by dehydration. The amount of the alkali catalyst used (in the form of an aqueous solution, calculated on a solids basis) is 0.01 to 2.0% by mass, preferably 0.02 to 0.5% by mass, based on the raw material (poly)alkylene glycol monoalkyl ether.

[0059] The present invention will be explained in more detail below with reference to examples. However, these examples are merely one embodiment of the invention, and the present invention is not limited thereto. Unless otherwise specified, operations are carried out at room temperature (20 to 25°C).

[0060] (Preparation of catalyst (1)) Tosoh Corporation's BEA-type zeolite (trade name: HSZ-930NHA, powder product, pore diameter: 6.5 Å, cation: template, SiO ２ / Al ２ O ３ Ratio: 27 (molar ratio), specific surface area: 590 m ２ / g (BET method), crystal size: 0.04 μm, particle size: 5 μm) was calcined in air at 500° C. for 4 hours to obtain catalyst (1).

[0061] (Calculation of Conversion, Selectivity, and Yield) The conversion, selectivity, and yield were calculated from the analytical values ​​of each layer obtained in the Examples and Comparative Examples by gas chromatography (GC) using the following formula: The conversion (olefin conversion (%)), selectivity ((poly)alkylene glycol monoalkyl ether selectivity (%)), and yield ((poly)alkylene glycol monoalkyl ether yield (%)) were calculated by adding up the values ​​for the following layers.

[0062] The analytical conditions for gas chromatography (GC) were as follows: <GC conditions> Gas chromatography device: Shimadzu Corporation, product name: Nexis ＴＭGC-2030 Column: Agilent Technologies, Inc., product name: DB-1 (column length: 60 m, inner diameter: 0.25 mm, film thickness: 0.25 μm) Detector: FID detection method Injection amount: 1 μl Linear velocity: 14 cm / sec Carrier gas: N ２ Temperature increase conditions: increase from 60°C to 100°C at 3°C / min, increase to 320°C at 10°C / min, and hold at 320°C for 30 minutes

[0063]

[0064] Example 1: 40 g (0.24 mol) of 1-dodecene, 59 g (0.95 mol) of monoethylene glycol, 105.5 g of diethylene glycol dimethyl ether, and 39.3 g of catalyst (1) were charged into a 500 ml glass reactor equipped with a stirring blade and a reflux condenser. The gas phase was replaced with nitrogen, and the mixture was maintained in a nitrogen atmosphere at atmospheric pressure. The temperature was then raised to 135°C while stirring at 650 rpm, and the reaction was carried out at that temperature for 4 hours. The liquid phase was homogeneous during the reaction. After the reaction, the reaction solution was cooled to 25°C and separated into two layers. 123.6 g of an upper layer (A) and 119.3 g of a lower layer (B) were obtained. The upper layer (A) and the lower layer (B) were analyzed by gas chromatography, and the conversion of 1-dodecene, as well as the selectivity and yield of ethylene glycol monododecyl ether, are shown in Table 1. Next, the separated lower layer (B) was filtered to remove the catalyst, and then 13.4 g of the solvent, diethylene glycol dimethyl ether, was distilled off by distillation (pressure: 4 kPa, tower top temperature: 80 to 100°C). The mixture was then cooled to 25°C and separated into two layers, yielding 19.8 g of an upper layer (C) and 46.8 g of a lower layer (D). The upper layers (A) and (C) were distilled at 1 kPa to distill off the solvent and raw material components at a tower top temperature of less than 140°C, yielding 18.9 g of ethylene glycol monododecyl ether at a tower top temperature of 140 to 143°C.

[0065] Example 2 A reaction was carried out in the same manner as in Example 1, except that the amount of diethylene glycol dimethyl ether was changed from 105.5 g to 193.9 g. The liquid phase was homogeneous during the reaction. After the reaction, the mixture was cooled to 25°C, but no phase separation of the liquid phase was observed. 90.1 g of the solvent, diethylene glycol dimethyl ether, was distilled off from the reaction mixture (pressure: 4 kPa, column top temperature: 80-100°C). The reaction mixture was then cooled to 25°C and separated into two layers. 122.2 g of an upper layer (A) and 118.0 g of a lower layer (B) were obtained. The upper layer (A) and the lower layer (B) were analyzed by gas chromatography, and the conversion of 1-dodecene, as well as the selectivity and yield of ethylene glycol monododecyl ether, are shown in Table 1. Next, the separated lower layer (B) was filtered to remove the catalyst, and then 13.2 g of the solvent, diethylene glycol dimethyl ether, was distilled off by distillation (pressure: 4 kPa, tower top temperature: 80 to 100°C). The mixture was then cooled to 25°C and separated into two layers, yielding 19.6 g of an upper layer (C) and 46.3 g of a lower layer (D). The upper layers (A) and (C) were distilled at 1 kPa to distill off the solvent and raw material components at a tower top temperature of less than 140°C, and 18.7 g of ethylene glycol monododecyl ether was obtained at a tower top temperature of 140 to 143°C.

[0066] Comparative Example 1 A reaction was carried out in the same manner as in Example 1, except that the amount of diethylene glycol dimethyl ether was changed from 105.5 g to 24.8 g. The reaction mixture separated into two layers during the reaction, and also separated into two layers when cooled to 25°C. 63.3 g of an upper layer (A) and 98.4 g of a lower layer (B) were obtained. The upper layer (A) and the lower layer (B) were analyzed by gas chromatography, and the conversion of 1-dodecene, as well as the selectivity and yield of ethylene glycol monododecyl ether, are shown in Table 1. The upper layer (A) was distilled at 1 kPa, and the solvent and raw material components at a column top temperature of less than 140°C were distilled off, yielding 12.3 g of ethylene glycol monododecyl ether at a column top temperature of 140 to 143°C.

[0067] Example 3: 40 g (0.20 mol) of 1-tetradecene, 50.6 g (0.82 mol) of monoethylene glycol, 105.0 g of diethylene glycol dimethyl ether, and 37.6 g of catalyst (1) were charged into a 500 ml glass reactor equipped with a stirring blade and a reflux condenser. The gas phase was replaced with nitrogen, and the mixture was maintained in a nitrogen atmosphere at atmospheric pressure. The temperature was then raised to 135°C while stirring at 650 rpm, and the reaction was carried out at that temperature for 4 hours. The liquid phase was homogeneous during the reaction. After the reaction, the reaction solution was cooled to 25°C and separated into two layers. 106.5 g of an upper layer (A) and 125.8 g of a lower layer (B) were obtained. The upper layer (A) and the lower layer (B) were analyzed by gas chromatography. The conversion of 1-tetradecene, as well as the selectivity and yield of ethylene glycol monotetradecyl ether, are shown in Table 1. Next, the separated lower layer (B) was filtered to remove the catalyst, and then 22.6 g of the solvent, diethylene glycol dimethyl ether, was distilled off by distillation (pressure: 4 kPa, tower top temperature: 80 to 100°C). The mixture was then cooled to 25°C and separated into two layers, yielding 18.7 g of an upper layer (C) and 46.9 g of a lower layer (D). The upper layers (A) and (C) were distilled at 0.5 kPa to distill off the solvent and raw material components at a tower top temperature of less than 142°C, and 15.6 g of ethylene glycol monotetradecyl ether was obtained at a tower top temperature of 142 to 145°C.

[0068] Example 4 A reaction was carried out in the same manner as in Example 1, except that the amount of catalyst (1) was changed from 39.3 g to 6.6 g. The liquid phase was homogeneous during the reaction. After the reaction, the reaction solution was cooled to 25°C and separated into two layers. 139.1 g of an upper layer (A) and 70.6 g of a lower layer (B) were obtained. The upper layer (A) and the lower layer (B) were analyzed by gas chromatography, and the conversion of 1-dodecene, as well as the selectivity and yield of ethylene glycol monododecyl ether, are shown in Table 1. Next, the separated lower layer (B) was filtered, and the catalyst was removed. 9.1 g of the solvent, diethylene glycol dimethyl ether, was then distilled off (pressure: 4 kPa, column top temperature: 80 to 100°C). The mixture was then cooled to 25°C and separated into two layers, yielding 14.5 g of an upper layer (C) and 40.5 g of a lower layer (D). The upper layers (A) and (C) were distilled at 1 kPa to remove the solvent and raw material components at a column top temperature of less than 140°C, and 17.2 g of ethylene glycol monododecyl ether was obtained at a column top temperature of 140 to 143°C.

[0069] Example 5 A reaction was carried out in the same manner as in Example 3, except that the amount of catalyst (1) was changed from 37.6 g to 5.6 g. The liquid phase was homogeneous during the reaction. After the reaction, the reaction solution was cooled to 25°C and separated into two layers. 128.4 g of an upper layer (A) and 70.8 g of a lower layer (B) were obtained. The upper layer (A) and the lower layer (B) were analyzed by gas chromatography, and the conversion of 1-tetradecene, as well as the selectivity and yield of ethylene glycol monotetradecyl ether, are shown in Table 1. Next, the separated lower layer (B) was filtered, and the catalyst was removed. 11.7 g of the solvent, diethylene glycol dimethyl ether, was then distilled off (pressure: 4 kPa, column top temperature: 80 to 100°C). The mixture was then cooled to 25°C and separated into two layers, yielding 13.6 g of an upper layer (C) and 39.9 g of a lower layer (D). The upper layers (A) and (C) were distilled at 0.5 kPa to remove the solvent and raw material components at a column top temperature of less than 142°C, and 14.5 g of ethylene glycol monotetradecyl ether was obtained at a column top temperature of 142 to 145°C.

[0070] Example 6 A reaction was carried out in the same manner as in Example 1, except that the amount of diethylene glycol dimethyl ether was changed from 105.5 g to 66 g. At the start of the reaction, the mixture separated into two layers, but the liquid phase during the reaction (the liquid phase 120 minutes after the temperature was raised to 135°C) was homogeneous. After the reaction, the reaction solution was cooled to 25°C and separated into two layers. 97.0 g of an upper layer (A) and 106.3 g of a lower layer (B) were obtained. The upper layer (A) and the lower layer (B) were analyzed by gas chromatography, and the conversion of 1-dodecene, as well as the selectivity and yield of ethylene glycol monododecyl ether, are shown in Table 1. The upper layer (A) was distilled at 1 kPa to remove the solvent and raw material components at a column top temperature of less than 140°C, and 18.6 g of ethylene glycol monododecyl ether was obtained at a column top temperature of 140 to 143°C.

[0071]

[0072] The (poly)alkylene glycol monoalkyl ether obtained by the present invention is useful as a raw material for surfactants. Furthermore, higher secondary alcohol alkoxylate adducts obtained by adding alkylene oxides thereto are useful as detergents, emulsifiers, fiber treatment agents, etc.

[0073] This application is based on Japanese Patent Application No. 2022-169503, filed on October 21, 2022, the disclosure of which is hereby incorporated by reference in its entirety.

Claims

1. A method for producing a (poly)alkylene glycol monoalkyl ether, comprising: a reaction step in which an olefin and a (poly)alkylene glycol are reacted in the form of a homogeneous liquid solution in the presence of a solvent at 110 to 250°C using a crystalline metallosilicate as a catalyst; a separation step in which the reaction solution obtained in the reaction step is separated into an upper layer (A) and a lower layer (B) at a temperature lower than 110°C; and a step in which the upper layer (A) separated in the separation step is distilled to obtain a (poly)alkylene glycol monoalkyl ether.

2. The method according to claim 1, further comprising the steps of distilling off the solvent component from the lower layer (B) separated in the separation step, separating the lower layer (B) into an upper layer (C) and a lower layer (D), and obtaining a (poly)alkylene glycol monoalkyl ether from the separated upper layer (C) by distillation.

3. 3. The process according to claim 1, wherein the olefin is at least one selected from the group consisting of acyclic olefins having 6 to 30 carbon atoms.

4. 3. The process according to claim 1, wherein the crystalline metallosilicate is a pentasil type metallosilicate or a BEA type metallosilicate.

5. 3. The method according to claim 1, wherein the solvent used in the reaction has a solubility parameter in the range of 16 to 20 and is a compound represented by the following formula (I): 【Chemistry 1】 In the above formula (I), R １ is a linear or branched alkyl group having 1 to 4 carbon atoms; R ２ is a linear or branched alkyl group having 1 to 4 carbon atoms or an acetyl group; A is a linear or branched alkylene group having 2 to 4 carbon atoms; and n is 1 to 4.

6. 3. A method for producing a higher secondary alcohol alkoxylate adduct, which comprises further adding an alkylene oxide to the (poly)alkylene glycol monoalkyl ether obtained by the method according to claim 1 or 2.