Process for producing a tertiary amine composition

Abstract

The present invention provides a method for producing a tertiary amine composition, said method comprising the steps (1) to (3) described below.　Step (1): an amination reaction step wherein dimethyl amine and an aliphatic aldehyde or an aliphatic alcohol having from 8 to 36 carbon atoms are reacted with each other in the presence of a metal catalyst Step (2): a distillation step wherein a reaction liquid obtained through the step (1) is separated into a concentrate and an evaporation product that contains a low-boiling-point compound by means of distillation Step (3): a centrifugal separation step wherein the concentrate obtained through the step (2) is separated into a sediment and a liquid layer that contains a tertiary amine composition by means of a centrifugal force

Description

Technical Field

[0001] The present invention relates to a method for producing a tertiary amine composition.

Background Art

[0002] Tertiary amines are important intermediate materials in the household and industrial fields, and quaternary ammonium salts obtained by quaternizing the tertiary amines are used in various applications such as rust inhibitors, bactericides, fabric softeners, shampoos, rinses, antistatic agents, detergents, dispersants, and textile auxiliaries.

[0003] Although various methods for producing tertiary amines are known, a technique for producing dimethylalkylamine as a main product by performing an amination reaction in the presence of a metal catalyst using an alcohol and a secondary amine as raw materials is typically cited (Japanese Patent Laid-Open No. 61-15865 (Patent Document 1)).

[0004] In addition, in the method for producing a tertiary amine described in Patent Document 1, it is known that in addition to obtaining dimethylalkylamine as a main product, methyldialkylamine is also obtained as a product.

[0005] In the conventional methods for producing tertiary amines, many studies have been conducted to obtain tertiary amines in high yields. In recent years, however, it has also been demanded to improve the product value by improving the hue of the obtained tertiary amines.

[0006] For example, Japanese Patent Laid-Open No. 2011-256245 (Patent Document 2) discloses a method for purifying transesterified oil and fat in which transesterification is performed using a sodium compound as a catalyst, and a calcium salt and / or a magnesium salt, and water are added to precipitate water-insoluble calcium soap and / or magnesium soap, followed by dehydration to further precipitate a sodium salt, and the calcium soap and / or magnesium soap, and the sodium salt are removed by filtration and / or centrifugation. In Patent Document 2, calcium soap, magnesium soap, and sodium salt are removed by filtration and / or centrifugation to achieve a high yield of transesterified oil and fat and a good color tone.

Summary of the Invention

[0007] The present invention relates to a method for producing a tertiary amine composition, including the following steps (1) to (3). Step (1): An amination reaction step of reacting an aliphatic alcohol or aliphatic aldehyde having 8 to 36 carbon atoms with dimethylamine in the presence of a metal catalyst Step (2): A distillation step of separating the reaction solution obtained through the above step (1) by distillation into an evaporation product containing low-boiling compounds and a concentrate Step (3): A centrifugation step of separating the concentrate obtained through the above step (2) by centrifugal force into a precipitate and a liquid layer containing a tertiary amine composition

Brief Description of the Drawings

[0008]

Figure 1

Modes for Carrying Out the Invention

[0009] Patent Document 2 is an invention made to achieve a good color tone, but it is a technique achieved only by a method for purifying transesterified oil and fat, and there is room for improvement in that it is not a technique applicable to a method for producing a tertiary amine composition. On the other hand, Patent Document 1 discloses a method for producing a tertiary amine using a metal catalyst. However, due to elution of the metal catalyst, etc., the product obtained through the production method of Patent Document 1 may contain coloring substances, and the hue of the product may be inferior. For this reason, in the method for producing a tertiary amine, a technique for improving the hue and enhancing the product value is required. Therefore, the present invention relates to a method for producing a tertiary amine composition that preferably removes low-boiling compounds and coloring substances and has a good hue (especially color tone).

[0010] The inventors of the present invention have intensively studied a production method for obtaining a tertiary amine composition with good hue, and have found that they can preferably remove low-boiling compounds and coloring substances, and provide a production method for a tertiary amine composition with good hue (especially color tone). That is, the present invention relates to a method for producing a tertiary amine composition, including the following steps (1) to (3). Step (1): An amination reaction step of reacting an aliphatic alcohol or aliphatic aldehyde having 8 to 36 carbon atoms with dimethylamine in the presence of a metal catalyst Step (2): A distillation step of separating the reaction solution obtained through the above step (1) by distillation into an evaporation product containing low-boiling compounds and a concentrate Step (3): A centrifugation step of separating the concentrate obtained through the above step (2) by centrifugal force into a precipitate and a liquid layer containing a tertiary amine composition

[0011] According to the present invention, it is possible to preferably remove low-boiling compounds and coloring substances, and provide a production method for a tertiary amine composition with good hue (especially color tone).

[0012] The production method of the tertiary amine composition of the present invention includes the following steps (1) to (3). Step (1): An amination reaction step of reacting an aliphatic alcohol or aliphatic aldehyde having 8 to 36 carbon atoms with dimethylamine in the presence of a metal catalyst Step (2): A distillation step of separating the reaction solution obtained through the above step (1) by distillation into an evaporation product containing low-boiling compounds and a concentrate Step (3): A centrifugation step of separating the concentrate obtained through the above step (2) by centrifugal force into a precipitate and a liquid layer containing a tertiary amine composition Thereby, it is possible to preferably remove low-boiling compounds and coloring substances, and provide a production method for a tertiary amine composition with good hue (especially color tone).

[0013] Here, as the "colored substance", substances colored due to the elution of the metal catalyst used in the amination reaction, substances derived from the eluted metal catalyst components colored by the heat history during the amination reaction step and the distillation step, and substances derived from the raw materials and products colored by the heat history during the amination reaction step and the distillation step, etc. are considered. As a general method for removing the colored substance, addition of a colored substance adsorbent such as activated carbon, activated clay, diatomaceous earth, etc. is considered. On the other hand, in the method of the present invention, it is considered that the eluted metal catalyst is reduced and precipitated as metal fine particles that can be removed in the centrifugation step. And by adsorbing the substances derived from the colored raw materials and products to this metal fine particle, it is considered that the colored substance can be effectively removed by the centrifugation step without adding a colored substance adsorbent, and an improvement in hue can be achieved. Also, by removing low-boiling compounds in the distillation step, it is considered that the concentration of the colored substance in the concentrate is increased, and the above adsorption can be efficiently performed.

[0014] [Step (1): Amination reaction step] In the amination reaction step of the present invention, an aliphatic alcohol or aliphatic aldehyde having 8 to 36 carbon atoms is reacted with dimethylamine in the presence of a metal catalyst. Also, in the amination reaction step of the present invention, reacting in the presence of hydrogen is preferable from the viewpoints of hue and reactivity. Further, after the amination reaction step and before the step (2): distillation step described later, including a filtration step is preferable from the viewpoints of hue and removing the metal catalyst.

[0015] In the amination reaction step of the present invention, when an alcohol is used as a starting material, first, an aliphatic alcohol having 8 to 36 carbon atoms (raw material alcohol) is dehydrogenated in the presence of a metal catalyst to generate an aldehyde, and this aldehyde and dimethylamine (raw material amine) come into contact in the reaction solution to generate enamine a. Next, hydrogen is added to enamine a generated in the reaction solution to obtain "dimethylalkylamine (RN(CH3)2)". Also, monomethylamine generated by disproportionation reaction from dimethylamine (raw material amine) and the aldehyde come into contact in the reaction solution to generate enamine b. Next, hydrogen is added to enamine b generated in the reaction solution to generate "methylalkylamine (RNH(CH3))", and further, this "methylalkylamine (RNH(CH3))" and the aldehyde come into contact in the reaction solution to generate enamine c. Next, hydrogen is added to enamine c generated in the reaction solution to obtain "methyldialkylamine (R2N(CH3))". Note that the aldehyde itself can also be used as a starting material for the amination reaction without using an alcohol. When a mixture of alcohols having different hydrocarbon groups or a mixture of aldehydes having different hydrocarbon groups is used as the starting alcohol or aldehyde, the two hydrocarbon groups (R) of methyldialkylamine (R2N(CH3)) may be different. Here, R is a hydrocarbon group derived from the aliphatic alcohol or aliphatic aldehyde, and the number of carbon atoms thereof is 8 or more and 36 or less.

[0016] The reaction mode of the amination reaction is not particularly limited, and it may be a suspension bed batch type, a fixed bed flow type or a fixed bed batch type, but it can be appropriately selected according to the catalyst activity, reaction scale, etc. Among them, the suspension bed type is preferable from the viewpoint of the hue improvement effect of the present invention. The reaction apparatus used for the amination reaction is not particularly limited. For example, a stirred tank type reaction apparatus shown in FIG. 1 can be used. When the stirred tank type reaction apparatus shown in FIG. 1 is used, first, a raw material alcohol or a raw material aldehyde is charged into the reaction tank, and then a metal catalyst is charged. While stirring the reaction solution in the reaction tank, the system is purged with an inert gas. After purging the system with an inert gas, the supply of hydrogen gas to the reaction tank is started, the reaction solution in the reaction tank is stirred, the temperature of the reaction solution is raised until it reaches a predetermined temperature, and after maintaining this temperature for a predetermined time, the supply of the raw material amine to the reaction tank is started, and the temperature of the reaction solution is gradually raised, and the amination reaction can be carried out while maintaining it at a predetermined temperature. The amination reaction is carried out until the unreacted raw material alcohol or raw material aldehyde in the reaction solution becomes less than or equal to a predetermined amount, and then the metal catalyst contained in the reaction solution can be removed by filtration. The raw material alcohol, raw material aldehyde, raw material amine, and metal catalyst used in the amination reaction are as follows.

[0017] <Raw material alcohol, raw material aldehyde> The raw material alcohol or raw material aldehyde used in the amination reaction step is an aliphatic alcohol or aliphatic aldehyde having 8 or more and 36 or less carbon atoms. Among them, from the viewpoint of easy availability, the aliphatic alcohol is preferable. The hydrocarbon group of the aliphatic alcohol or aliphatic aldehyde may be any of linear, branched, or cyclic hydrocarbon groups, and may be a saturated or unsaturated hydrocarbon group. From the viewpoint of reactivity, the number of carbon atoms of the aliphatic alcohol or aliphatic aldehyde is preferably 8 or more, more preferably 10 or more, still more preferably 12 or more, and preferably 30 or less, more preferably 26 or less, still more preferably 22 or less.

[0018] <Raw material amine> The raw material amine used in the amination reaction is dimethylamine. The raw material amine may be continuously or intermittently supplied to the reaction tank, but it is preferably adjusted as appropriate according to the progress of the amination reaction. When the raw material amine is continuously supplied to the reaction tank, from the viewpoint of reactivity, it is preferably 5 L / hr or more, more preferably 7 L / hr or more, still more preferably 9 L / hr or more, and preferably 100 L / hr or less, more preferably 95 L / hr or less, still more preferably 90 L / hr or less per 1 kg of the raw material alcohol or raw material aldehyde. The raw material amine may be in a gaseous state.

[0019] <Metal catalyst> The metal catalyst used in the amination reaction is not particularly limited, and for example, transition metal catalysts such as copper-based catalysts and nickel-based catalysts, and noble metal catalysts such as ruthenium-based catalysts can be used. Examples of the copper-based catalyst include those described in JP-A-2-233 (a catalyst of one or more transition metals selected from Cu, Cr, Mu, Fe, Ni, Co, Zn - platinum group element - an alkali metal such as Li, Mg, an alkaline earth metal catalyst), JP-A-2-234 (a fourth-period transition metal element such as Cu - Ni, Co - platinum group element - a fourth component such as Al), and JP-A-2001-151733 (a Cu - fourth-period transition metal - platinum group element catalyst). Examples of the nickel-based catalyst include those described in JP-A-50-30804 (Ni - Cu - Cr catalyst), JP-A-7-69999 (Ni catalyst), JP-T-2005-527516 (Ni - Cu - Co - ZrO2 catalyst), and JP-A-2007-176889 (Ni - Cu - alkali metal catalyst). Examples of ruthenium-based catalysts include those described in JP-A-8-243392 (Ru-porous oxide catalyst), EP 729785 (Ru-noble metal catalyst), JP-A-2008-150312 (Ru-ZrO2 composite oxide and / or metal surface-treated ZrO2 catalyst), JP-A-2007-176891 (Ru-porous oxide catalyst), JP-A-2007-176892 (catalyst containing at least one metal component selected from Ru-Ni and Co and at least one metal component selected from La, Y, Mg, and Ba), and US Patent No. 4912260 (catalyst containing at least one metal component selected from Ru-Ni-Pd, Re, and Ir).

[0020] From the perspective of reactivity, the metal catalyst is preferably a catalyst having at least one selected from the group consisting of copper, nickel, cobalt, iron, ruthenium, platinum, rhodium, palladium, molybdenum, tungsten, and rhenium as a main active component. When the metal catalyst contains copper as a main active component and another main active component, the other main active component preferably contains at least one selected from the following (i) Group 4 transition metals, (ii) platinum and Group 5 transition metals, and (iii) alkali metals and alkaline earth metals, and a catalyst satisfying any one of the following conditions (a) to (c) is preferred. The ratios in conditions (a) to (c) are metal molar ratios. (i) Group 4 transition metals: at least one selected from nickel, cobalt, iron, chromium, and zinc. (ii) Platinum and Group 5 transition metals: at least one selected from platinum, palladium, ruthenium, and rhodium. (iii) Alkali metals and alkaline earth metals: at least one selected from lithium, sodium, potassium, rubidium, cesium, magnesium, calcium, strontium, and barium.

[0021] · Condition (a): copper / Group 4 transition metal = 1 / 9 to 99 / 1, preferably 50 / 50 to 99 / 1 · Condition (b): platinum and Group 5 transition metals / (copper + Group 4 transition metals) = 0 to 0.1, preferably 0 to 0.05 ·Condition (c): The ratio of the Group 4 transition metal to (alkali metal + alkaline earth metal) is 1 / 0 to 1 / 2, preferably 1 / 0 to 1 / 1.

[0022] Among the metal catalysts, a catalyst containing copper and a Group 4 transition metal (especially nickel), a catalyst containing copper and platinum or a Group 5 transition metal (especially ruthenium), and a catalyst containing copper, a Group 4 transition metal (especially nickel), and a Group 5 transition metal (especially ruthenium) are preferred. Among them, a catalyst containing copper and a Group 4 transition metal (especially nickel) is more preferred. The metal catalyst can be used by supporting the main active component on a porous carrier such as a metal oxide or a composite oxide. There is no particular limitation on its shape, and it may be in the form of powder, sphere, cylinder (pellet), or film. The metal catalysts can be used alone or in combination of two or more.

[0023] The metal catalyst may be in an unreduced state or a reduced state, but from the viewpoint of reactivity, a reduced one is preferred. The reduced metal catalyst can be prepared by performing reduction in a reducing atmosphere such as hydrogen gas. Therefore, for example, it can also be prepared in a step of putting an unreduced metal catalyst into a reaction vessel together with a raw material alcohol and then raising the temperature to the reaction temperature while introducing hydrogen gas.

[0024] The amount of the metal catalyst used is preferably adjusted appropriately according to the reaction method. From the viewpoints of hue and reactivity, the amount of the metal catalyst used is preferably 0.05 part by mass or more, more preferably 0.1 part by mass or more, and preferably 10 parts by mass or less, more preferably 1 part by mass or less, based on the total mass of the raw material alcohol or the raw material aldehyde. The reaction method is not particularly limited. Examples include a suspension bed batch method, a fixed bed batch method, a fixed bed continuous method, and a semi-batch method combining them. Among them, the suspension bed method is preferred from the viewpoint of the hue improving effect of the present invention.

[0025] <Reaction conditions for the amination reaction> In the amination reaction step, the reaction temperature before supplying the raw material amine (dimethylamine) after supplying hydrogen gas to the reaction tank (reaction solution) is appropriately determined in consideration of the boiling point of the raw material alcohol. However, from the viewpoints of hue and reactivity, it is preferably 150 °C or higher, more preferably 160 °C or higher, still more preferably 170 °C or higher, and preferably 220 °C or lower, more preferably 210 °C or lower, still more preferably 200 °C or lower.

[0026] The reaction temperature after supplying the raw material amine to the reaction tank (reaction solution) is appropriately determined in consideration of the boiling point of the raw material alcohol. However, from the viewpoints of hue and reactivity, it is preferably 160 °C or higher, more preferably 170 °C or higher, still more preferably 180 °C or higher, and preferably 300 °C or lower, more preferably 250 °C or lower, still more preferably 230 °C or lower.

[0027] In the amination reaction step, a part of the reaction solution in the reaction tank is appropriately sampled over time, and the introduction of the raw material amine is stopped when the unreacted raw material alcohol or raw material aldehyde in the reaction solution reaches 1.5% by mass or less, and this is taken as the reaction end point. Note that the quantification of the unreacted raw material alcohol or raw material aldehyde can be carried out by the method described in the examples using a gas chromatograph.

[0028] The supply amount of hydrogen gas is preferably 15 L / hr or more, more preferably 20 L / hr or more, per 1 kg of the raw material alcohol or raw material aldehyde, and preferably 45 L / hr or less, more preferably 40 L / hr or less, still more preferably 35 L / hr or less.

[0029] [Step (2): Distillation step] In the distillation step of the present invention, the reaction solution obtained through the amination reaction step is separated by distillation into an evaporation product containing low-boiling compounds and a concentrate. Here, the "low-boiling compounds" are appropriately determined in consideration of the boiling point of the raw material alcohol. For example, when the number of carbon atoms is 12, it refers to compounds having a boiling point of 280 °C or lower.

[0030] In the distillation step of the present invention, the reaction solution obtained through the amination reaction step is charged into a container such as a flask, and using a distillation machine under predetermined distillation conditions, a distillation separation operation is performed to separate it into an evaporation product containing low-boiling compounds and a concentrate.

[0031] <Distillation conditions> From the viewpoints of hue and distillation efficiency, the distillation temperature is preferably 70°C or higher, more preferably 90°C or higher, still more preferably 110°C or higher, and preferably 300°C or lower, more preferably 250°C or lower, still more preferably 200°C or lower. Also, the degree of vacuum is appropriately adjusted according to the distillation temperature, but is preferably 0.01 kPa or higher, more preferably 0.05 kPa or higher, still more preferably 0.1 kPa or higher, and preferably 5 kPa or lower, more preferably 3 kPa or lower, still more preferably 1 kPa or lower.

[0032] The concentrate obtained through the distillation step preferably contains 50% by mass or more, more preferably 70% by mass or more, still more preferably 75% by mass or more of the dialkylmethylamine represented by the following formula (I). Formula (I): R2N(CH3) (In the above formula (I), R is a hydrocarbon group derived from the aliphatic alcohol or aliphatic aldehyde, and the number of carbon atoms thereof is 8 or more and 36 or less.) It should be noted that the qualitative and quantitative analysis of the concentrate obtained through the distillation step can be carried out by collecting a part of the concentrate recovered through the distillation step and using a gas chromatograph according to the method described in the examples.

[0033] Also, the concentrate obtained by distillation separation through the distillation step preferably contains 1% by mass or more, more preferably 3% by mass or more, still more preferably 5% by mass or more, and preferably 20% by mass or less, more preferably 18% by mass or less, still more preferably 15% by mass or less of the ester compound. Here, the ester compound refers to an ester compound formed from a fatty acid, which is a saturated or unsaturated aliphatic carboxylic acid having 8 to 36 carbon atoms, and an alcohol having 8 to 36 carbon atoms. Among them, it particularly refers to a fatty acid monoester compound having 8 to 36 carbon atoms formed from a monovalent fatty acid, which is a saturated or unsaturated aliphatic carboxylic acid, and a monovalent alcohol.

[0034] On the other hand, the evaporation product obtained by distillation separation through the distillation step contains an alkyldimethylamine represented by the following formula (II) as a low-boiling compound, preferably 50% by mass or more, more preferably 70% by mass or more, and still more preferably 75% by mass or more. Formula (II): RN(CH3)2 (In the above formula (II), R is a hydrocarbon group derived from the aliphatic alcohol or aliphatic aldehyde, and the number of carbon atoms thereof is 8 to 36.)

[0035] [Step (3): Centrifugation step] In the centrifugation step of the present invention, the concentrate obtained through the distillation step is separated by centrifugal force into a precipitate and a supernatant liquid (liquid layer) containing a tertiary amine composition. Here, the "tertiary amine composition" refers to a composition containing a dialkylmethylamine represented by the above formula (I), preferably 50% by mass or more, more preferably 70% by mass or more, and still more preferably 75% by mass or more.

[0036] In the centrifugation step of the present invention, the reaction method is not particularly limited. Examples include a suspension bed batch type, a fixed bed batch type, a fixed bed continuous type, and a semi-batch type combining them. Among them, the suspension bed type is preferable from the viewpoint of the hue improvement effect of the present invention. A centrifugation operation is performed to separate the concentrate obtained through the distillation step into a precipitate and a supernatant liquid (liquid layer) under predetermined centrifugation conditions. The centrifuge is not particularly limited. Examples include a disk type continuous centrifuge, a decanter type continuous centrifuge, and a batch type centrifuge. The centrifuge used here is not particularly limited, and examples thereof include centrifuges such as "CR22N ROTAR R15A" manufactured by Hitachi, Ltd.

[0037] <Centrifugation conditions> The centrifugal force required for the centrifugation is preferably 500 G or more, more preferably 1000 G or more, still more preferably 1500 G or more, and preferably 30000 G or less, more preferably 25000 G or less, still more preferably 20000 G or less, from the viewpoint of suitably removing the coloring substance. The centrifugation time is appropriately adjusted according to the centrifugal force. When the centrifugal force is 500 G or more, it is preferably 20 minutes or more, more preferably 30 minutes or more, still more preferably 60 minutes or more. When the centrifugal force is 1000 G or more, it is preferably 10 minutes or more, more preferably 15 minutes or more, still more preferably 30 minutes or more. When the centrifugal force is 1500 G or more, it is preferably 7 minutes or more, more preferably 10 minutes or more, still more preferably 20 minutes or more. Although the longer the centrifugation time, the more effective it is, considering efficiency, it is within 120 minutes. Regarding the centrifugation temperature, generally, the higher the temperature, the lower the viscosity of the liquid, which is advantageous for separation. It is preferably 5°C or more, more preferably 10°C or more, still more preferably 20°C or more. On the other hand, from the viewpoint of operation safety, it is preferably 95°C or less, more preferably 90°C or less, still more preferably 80°C or less.

[0038] [Quaternary ammonium salt composition] The tertiary amine composition obtained by the production method of the present invention can be quaternized to obtain a quaternary ammonium salt composition. The method for quaternizing a tertiary amine composition to obtain a quaternary ammonium salt composition is not particularly limited, and known methods can be used. For example, the supernatant (liquid phase) recovered through the centrifugation step is put into a container such as a flask, and a predetermined amount of a quaternizing agent is added to this container and heated at a predetermined temperature for a predetermined time to obtain it. Examples of the quaternizing agent include alkyl halides having 1 to 8 carbon atoms (such as methyl chloride), benzyl halides (such as benzyl chloride), dialkyl (having 1 to 2 carbon atoms) sulfates (dimethyl sulfate and diethyl sulfate), and dialkyl (having 1 to 2 carbon atoms) alkyl carbonates (such as dimethyl carbonate).

[0039] [Tertiary amine salt composition] The tertiary amine composition obtained by the production method of the present invention can be reacted with an acid to obtain a tertiary amine salt composition. The method for reacting a tertiary amine composition with an acid to obtain a tertiary amine salt composition is not particularly limited, and a known method can be used. For example, the supernatant liquid (liquid phase) recovered through the centrifugation step is put into a container such as a flask, and a predetermined amount of an inorganic acid or an organic acid is added to this container, and it can be obtained by heating at a predetermined temperature for a predetermined time. Examples of the inorganic acid include hydrochloric acid, sulfuric acid, and the like. Examples of the organic acid include monovalent or polyvalent carboxylic acids having 1 to 10 carbon atoms, and monovalent or polyvalent sulfonic acids having 1 to 20 carbon atoms. More specifically, methyl sulfuric acid, ethyl sulfuric acid, p-toluenesulfonic acid, (o-, m-, p-) xylenesulfonic acid, benzenesulfonic acid, dodecylbenzenesulfonic acid, glycolic acid, ethylenediaminetetraacetic acid, citric acid, benzoic acid, salicylic acid, succinic acid, and the like can be mentioned.

Examples

[0040] The present invention will be described in more detail with reference to examples, but the present invention is not limited by these examples. In the examples, a stirred tank type reactor equipped with a reaction tank and a condenser shown in FIG. 1 was used, and lauryl alcohol and dimethylamine were used as raw materials.

[0041] (Example 1) (1) Step (1): Amination reaction step Into a 2 L separable flask as a reaction vessel, 800 g of lauryl alcohol (manufactured by Kao Corporation, trade name: Calcohol 2098), which is a raw material alcohol, was charged. Then, 0.3 parts by mass of a powdery Cu / Ni catalyst as a metal catalyst was charged with respect to the total mass of the raw material alcohol, and the inside of the system was purged with nitrogen while stirring the reaction solution in the reaction vessel. After purging the inside of the system with nitrogen, the supply of hydrogen gas to the reaction vessel was started, the reaction solution in the reaction vessel was stirred, the temperature of the reaction solution was raised to 180 °C, and after maintaining this temperature for about 15 minutes, the supply of dimethylamine gas, which is a raw material amine, to the reaction vessel was started, and the temperature of the reaction solution was gradually raised, and an amination reaction was carried out while maintaining it at 220 °C. In addition, the supply of the hydrogen gas was carried out at a flow rate of 20 L / hr per 1 kg of the raw material alcohol, and the supply of the dimethylamine gas was adjusted to a flow rate of 10 to 80 L / hr per 1 kg of the raw material alcohol according to the progress of the amination reaction. The amination reaction was carried out until the unreacted lauryl alcohol in the reaction solution became 1% by mass or less. The metal catalyst contained in the reaction solution was removed by filtration to obtain a tertiary amine composition.

[0042] (2) Step (2): Distillation step Among the reaction solutions obtained through the above step (1), 560 mL of a part of the reaction solution was charged into a 1 L flask, and a distillation operation was carried out under the distillation conditions shown below. <Distillation conditions> · Distillation temperature: 150 °C · Vacuum degree: 0.6 kPa By the above distillation operation, an evaporation product containing low-boiling compounds was removed, and 20 g of a concentrate in the flask was recovered.

[0043] (3) Step (3): Centrifugation step 30 g was taken from the concentrates obtained by repeating the above step (2) and put into a 50 mL bottle, loaded into a centrifuge (manufactured by Hitachi, Ltd., trade name: CR22N ROTAR R15A), and a centrifugation operation was carried out under the centrifugation conditions shown below. <Centrifugation conditions> · Centrifugal force: 1500 G ·Processing time: 10 minutes ·Processing temperature: 22°C By the centrifugation operation, the concentrate in the bottle was separated into 5 g of precipitate and 25 g of supernatant liquid (liquid phase) containing a tertiary amine composition, and the recovered liquid phase was subjected to a hue test.

[0044] (Example 2) In Example 1, the same operations as in Example 1 were performed except that in step (3): the centrifugal force in the centrifugation step was changed to 3000G.

[0045] (Example 3) In Example 1, the same operations as in Example 1 were performed except that in step (3): the centrifugal force in the centrifugation step was changed to 10000G.

[0046] (Example 4) In Example 1, the same operations as in Example 1 were performed except that 5 g of the liquid phase recovered through the centrifugation step in step (3) was put into a 300 mL flask, 40 g of ethanol and 5 g of 35% by mass hydrochloric acid aqueous solution were added, heated at 60°C for 20 minutes, and the tertiary amine hydrochloride composition obtained by reacting with hydrochloric acid was subjected to a hue test.

[0047] (Example 5) In Example 2, the same operations as in Example 2 were performed except that 5 g of the liquid phase recovered through the centrifugation step in step (3) was put into a 300 mL flask, 40 g of ethanol and 5 g of 35% by mass hydrochloric acid aqueous solution were added, heated at 60°C for 20 minutes, and the tertiary amine hydrochloride composition obtained by reacting with hydrochloric acid was subjected to a hue test.

[0048] (Example 6) In Example 3, the same operations as in Example 3 were performed except that 5 g of the liquid phase recovered through the centrifugation step in step (3) was put into a 300 mL flask, 40 g of ethanol and 5 g of 35% by mass hydrochloric acid aqueous solution were added, heated at 60°C for 20 minutes, and the tertiary amine hydrochloride composition obtained by reacting with hydrochloric acid was subjected to a hue test.

[0049] (Comparative Example 1) In Example 1, the same operations as in Example 1 were performed, except that in step (3): the centrifugation step was not performed, and the concentrate recovered through step (2): the distillation step was subjected to a hue test.

[0050] (Comparative Example 2) In Example 1, the same operations as in Example 1 were performed, except that in step (3): the centrifugation step was not performed, and the concentrate recovered through step (2): the distillation step was filtered under the filtration conditions shown below, separated into a residue and a filtrate, and the recovered filtrate was subjected to a hue test. <Filtration Conditions> · Filter paper: Quantitative filter paper No. 5C manufactured by ADVANTEC

[0051] (Comparative Example 3) In Comparative Example 1, the same operations as in Comparative Example 1 were performed, except that 5 g of the concentrate recovered through step (2): the distillation step was placed in a 300 mL flask, 40 g of ethanol and 5 g of a 35 mass% hydrochloric acid aqueous solution were added, heated at 60 °C for 20 minutes, and the tertiary amine hydrochloride composition obtained by reacting with hydrochloric acid was subjected to a hue test.

[0052] (Comparative Example 4) In Comparative Example 2, the same operations as in Comparative Example 2 were performed, except that 5 g of the filtrate separated into a residue and a filtrate by filtration was placed in a 300 mL flask, 40 g of ethanol and 5 g of a 35 mass% hydrochloric acid aqueous solution were added, heated at 60 °C for 20 minutes, and the tertiary amine hydrochloride composition obtained by reacting with hydrochloric acid was subjected to a hue test.

[0053] [Measurement by Gas Chromatograph] In step (1): the amination reaction step of Example 1, a part of the reaction solution in a 2 L separable flask as the reaction vessel was sampled over time, and using a gas chromatograph (manufactured by Agilent Technologies Co., Ltd., product name: 6500 Network GC), under the measurement conditions shown below, with the total peak area set to 100%, unreacted lauryl alcohol was quantified. <Measurement Conditions> · Column: DB-17HT (inner diameter 0.25 mm × length 15 m, film thickness 0.15 μm) · Oven temperature: 60°C → 320°C · Detector temperature: 325°C · Detector: FID

[0054] Also, in step (2) of Example 1: A part of the concentrate recovered through the distillation step was sampled, and the sample was subjected to qualitative analysis of the concentrate composition under the same measurement conditions as above using the same gas chromatograph as above. The quantitative analysis of the composition was performed with the total peak area set to 100%, and the results are shown in Table 1.

[0055]

Table 1

[0056] [Hue test] In Examples 1 to 3, the supernatant (liquid phase) recovered through the centrifugation step, in Comparative Example 1, the concentrate recovered through the distillation step, and in Comparative Example 2, the filtrate recovered through the filtration treatment were used as Samples 1 to 5 of the tertiary amine composition, respectively, and the following hue test was performed, and the results are shown in Table 2. Also, each of the tertiary amine hydrochloride compositions obtained in Examples 4 to 6 and Comparative Examples 3 to 4 was used as Index Samples 6 to 10 for hue, and the following hue test was performed, and the results are shown in Table 3. <Degree of coloration (APHA)> The Hazen color number (APHA) of each of Samples 1 to 10 was measured using an ultraviolet-visible spectrophotometer (manufactured by Tintometer, product name: Lovibond Tintometer PFX990) in accordance with JIS K 0071-2:1998 using a 1-inch cell. Note that the smaller the APHA value, the less colored it can be evaluated. <Color tone> For each of Samples 1 to 10, the color tone was measured using a tintometer (manufactured by Tintometer, product name: Lovibond Tintometer PFX990) in accordance with JIS K 0071-2:1998, with R (red), Y (yellow), B (blue), and N (neutral color) measured using a 1-inch cell respectively. Note that the smaller the color tone value, the less coloring can be evaluated.

[0057]

Table 2

[0058]

Table 3

[0059] (Summary of Results 1) From the results of the hue test of the tertiary amine compositions shown in Table 2, the following was found. The tertiary amine compositions of Examples 1 to 3, due to undergoing a centrifugation step for the concentrate obtained through the distillation step defined in the present invention, were found to have better hue (especially color tone) compared to the tertiary amine compositions of Comparative Examples 1 and 2 obtained without undergoing the centrifugation step. Note that the tertiary amine composition of Comparative Example 2 was obtained through a filtration step, but was found to have inferior hue (especially color tone) compared to the tertiary amine compositions of Examples 1 to 3.

[0060] (Summary of Results 2) From the results of the hue test of the tertiary amine hydrochloride compositions shown in Table 3, the following was found. The tertiary amine hydrochloride compositions of Examples 4 to 6, due to being obtained from the tertiary amine compositions that underwent a centrifugation step for the concentrate obtained through the distillation step defined in the present invention, were found to have better hue compared to the tertiary amine hydrochloride compositions of Comparative Examples 3 and 4 obtained from the tertiary amine compositions without undergoing the centrifugation step. The tertiary amine hydrochloride composition of Comparative Example 4 was obtained from the tertiary amine composition obtained through the filtration step, but it was found that the hue was inferior compared to the tertiary amine hydrochloride compositions of Examples 4 to 6.

Claims

1. A method for producing a tertiary amine composition, comprising the following steps (1) to (3). Step (1): An amination reaction step of reacting an aliphatic alcohol or aliphatic aldehyde having 8 to 36 carbon atoms with dimethylamine in the presence of a metal catalyst Step (2): A distillation step of separating the reaction solution obtained through the above step (1) by distillation into an evaporation product containing low-boiling compounds and a concentrate Step (3): A centrifugation step of separating the concentrate obtained through the above step (2) by centrifugal force into a precipitate and a liquid layer containing a tertiary amine composition

2. In the above step (3): centrifugation step, The method for producing a tertiary amine composition according to claim 1, wherein the centrifugal force is 1000 G or more and 25000 G or less.

3. In the above step (2): distillation step, The method for producing a tertiary amine composition according to claim 1 or 2, wherein the concentrate contains 50% by mass or more of a dialkylmethylamine represented by the following formula (I). Formula (I): R ２ N(CH ３ ) (In the above formula (I), R is a hydrocarbon group derived from the aliphatic alcohol or aliphatic aldehyde, and the number of carbon atoms thereof is 8 to 36.)

4. In the above step (2): distillation step, The method for producing a tertiary amine composition according to any one of claims 1 to 3, wherein the concentrate contains 5% by mass or more of an ester compound.

5. In the above step (2): distillation step, The method for producing a tertiary amine composition according to any one of claims 1 to 4, wherein the distillation temperature is 70°C or more and 300°C or less.

6. The method for producing a tertiary amine composition according to any one of claims 1 to 5, wherein after the above step (1): amination reaction step and before the above step (2): distillation step, a filtration step is included.

7. In the step (1): the amination reaction step, A method for producing a tertiary amine composition according to any one of claims 1 to 6, wherein the reaction is carried out in the presence of hydrogen.

8. In the step (1): the amination reaction step, A method for producing a tertiary amine composition according to any one of claims 1 to 7, wherein the metal catalyst is a catalyst having at least one selected from the group consisting of copper, nickel, cobalt, iron, ruthenium, platinum, rhodium, palladium, molybdenum, tungsten, and rhenium as a main active ingredient.

9. A method for producing a quaternary ammonium salt composition, comprising: a step of obtaining a tertiary amine composition by the method for producing a tertiary amine composition according to any one of claims 1 to 8; and a step of quaternizing the obtained tertiary amine composition to obtain a quaternary ammonium salt composition.

10. A method for producing a tertiary amine salt composition, comprising: a step of obtaining a tertiary amine composition by the method for producing a tertiary amine composition according to any one of claims 1 to 8; and a step of reacting the obtained tertiary amine composition with an acid to obtain a tertiary amine salt composition.

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