JP2022117589A - Method for producing secondary alcohol alkoxylate - Google Patents

Abstract

To provide means that can reduce the coloring of a secondary alcohol alkoxylate.SOLUTION: A method for producing a secondary alcohol alkoxylate includes reacting a secondary alcohol with an alkylene oxide in the presence of a catalyst to obtain a reaction liquid containing an alkylene oxide adduct, mixing the reaction liquid with water, and then letting the mixture stand at a temperature over 60°C to separate it into an aqueous layer and an organic layer, obtaining a liquid containing a secondary alcohol alkoxylate precursor represented by formula (1): CmH2m+1[O(XO)nH] (where, X is a C1 to 3 alkylene group; m is 11 to 15; and n is more than 0 and less than 2.1), purifying the liquid, to obtain a secondary alcohol alkoxylate represented by formula (2): CmH2m+1[O(XO)pH] (where, X and m have the same meanings as those in the formula (1); p is 2.5 to 3.5).SELECTED DRAWING: None

Description

The present invention relates to a method for producing secondary alcohol alkoxylates.

Secondary alcohol alkoxylates, including secondary alcohol ethoxylates, are widely used as nonionic surfactants because of their low pour points and easy handling. This secondary alcohol alkoxylate is prepared in the presence of an alkaline catalyst such as sodium hydroxide, potassium hydroxide, sodium alkoxide or an acidic catalyst such as boron trifluoride, boron trifluoride-complex, antimony pentachloride, tin tetrachloride. is produced by adding an alkylene oxide to a secondary alcohol as a starting material (for example, Patent Document 1).

JP-A-61-186337

In recent years, from the viewpoint of increasing added value, there has been a demand for reducing the coloring of secondary alcohol alkoxylates.

Accordingly, the present invention has been made in view of the above circumstances, and an object of the present invention is to provide means capable of reducing the coloring of secondary alcohol alkoxylates.

The present inventors have conducted intensive research in order to solve the above problems. As a result, after mixing the reaction solution containing the alkylene oxide adduct with water, it was allowed to stand still at a specific temperature to separate into an aqueous layer and an organic layer to produce a secondary alcohol alkoxylate having a small number of alkylene oxide additions. The inventors have found that the above-mentioned problems can be solved by obtaining a liquid containing the compound and purifying this liquid, and completed the present invention.

That is, the above object is to react a secondary alcohol with an alkylene oxide in the presence of a catalyst to obtain a reaction liquid containing an alkylene oxide adduct, mix the reaction liquid with water, and then statically react at a temperature exceeding 60°C. to separate into an aqueous layer and an organic layer, formula (1): C _m H _2m+1 [O(XO) _n H] (wherein X represents an alkylene group having 1 to 3 carbon atoms; m is 11 to 15; n is greater than 0 and less than 2.1) to obtain a liquid containing a secondary alcohol alkoxylate precursor represented by the formula (2): C _m H _2m+1 [O(XO) _p H] (in formula (2), X and m have the same definitions as in formula (1); p is 2.5 to 3.5) It can be achieved by a method for producing a secondary alcohol alkoxylate, comprising obtaining a secondary alcohol alkoxylate.

According to the present invention, coloring of secondary alcohol alkoxylates can be reduced.

FIG. 1 is a schematic diagram illustrating one embodiment of the manufacturing process of the present invention. FIG. 2 shows a mixer-settler type apparatus for mixing an alkylene oxide adduct with water and separating it into an aqueous layer and an organic layer. FIG. 3 is a diagram showing an example of a reactor for secondary alcohol and alkylene oxide. FIG. 4 is a diagram showing an example of a tubular reactor used for the second alkoxylation reaction. FIG. 5 shows an alkylene oxide supply part _Pn′ installed n′ from the inlet side of the tubular reactor in FIG. 4 and an alkylene oxide supply unit installed n′+1 from the inlet side of the tubular reactor. FIG. 11 is a diagram for explaining an interval [X _n′ (m)] with a portion P _n′+1 ;

The first of the present invention is to react a secondary alcohol with an alkylene oxide in the presence of a catalyst to obtain a reaction liquid containing an alkylene oxide adduct, and after mixing the reaction liquid with water, at a temperature exceeding 60 ° C. The aqueous layer and the organic layer were separated by standing, and the formula (1): C _m H _2m+1 [O(XO) _n H] (in formula (1), X represents an alkylene group having 1 to 3 carbon atoms). m is 11 to 15; n is greater than 0 and less than 2.1) to obtain a liquid containing a secondary alcohol alkoxylate precursor represented by the formula (2) : C _m H _2m+1 [O(XO) _p H] (in formula (2), X and m have the same definitions as in formula (1); p is 2.5 to 3.5) A method (first aspect) for producing a secondary alcohol alkoxylate comprising obtaining a secondary alcohol alkoxylate having a

A second aspect of the present invention is the formula (2) having a hue (APHA) of less than 45: C _m H _2m+1 [O(XO) _p H] (wherein X is an alkylene having 1 to 3 carbon atoms) m is from 12 to 14; p is from 2.5 to 3.5).

An embodiment according to one aspect of the present invention will be described below. The present invention is not limited only to the following embodiments.

In the present specification, the range “X to Y” includes X and Y and means “X or more and Y or less”. Unless otherwise specified, measurements of operations and physical properties are performed under the conditions of room temperature (20 to 25° C.)/relative humidity of 40 to 50% RH.

<Method for producing secondary alcohol alkoxylate>
In one aspect of the present invention, i) reacting a secondary alcohol with an alkylene oxide in the presence of a catalyst to obtain a reaction liquid containing an alkylene oxide adduct (step (i)); ii) reacting the reaction liquid with water; After mixing, the aqueous and organic layers were separated by standing at a temperature above 60° C. to obtain formula (1): C _m H _2m+1 [O(XO) _n H] (where X is Represents an alkylene group having 1 to 3 carbon atoms; m is 11 to 15; n is more than 0 and less than 2.1) to obtain a liquid containing a secondary alcohol alkoxylate precursor (step (ii)); iii) purifying the liquid containing the secondary alcohol alkoxylate precursor to formula (2): C _m H _{2m +1} [O(XO) pH] (wherein X and m is the same definition as in formula (1) above; p is 2.5 to 3.5). A method for producing an alcohol alkoxylate (first aspect).

The inventors of the present invention have extensively studied how to reduce the coloring of secondary alcohol ethoxylates. As a result, the cause of the coloring was considered to be the number of moles of alkylene oxide added and the separation conditions when removing impurities due to the alkylene oxide addition reaction. That is, for example, in the reaction of a secondary alcohol and ethylene oxide in the presence of a catalyst (especially an acid catalyst), the catalyst (especially an acid catalyst) and further reaction by-products such as polyethylene glycol and dioxane (collectively, (also referred to as a “coloring inducer”) causes coloration. These coloring-inducing substances theoretically migrate to the water layer side when the alkylene oxide adduct is mixed with water, and therefore can be removed by separating from the organic layer containing the alkylene oxide adduct. However, even by mixing the alkylene oxide adduct with water, there were cases where the coloration-inducing substance could not be efficiently separated. As a result of further studies on the subject, (a) the number of alkylene oxide addition moles (hereinafter also referred to as “the number of AO addition moles”) and (b) the standing temperature when separating the organic layer and the aqueous layer We speculated that the control was effective in reducing coloration (efficient removal of color-causing substances). Regarding (a), an alkylene oxide adduct with a high AO addition mole number (hereinafter also referred to as a secondary alcohol alkylene oxide high adduct) generates micelles when mixed with water, and the aqueous layer and the organic layer are separated. It was speculated that an emulsified layer was formed during the process, the water layer could not be separated well, and the coloring-inducing substances present in the water layer could not be sufficiently removed. Therefore, the relationship between the number of moles of AO added to the alkylene oxide adduct and the emulsified layer was further studied. As a result, by controlling the alkylene oxide addition mole number of the alkylene oxide adduct (secondary alcohol alkoxylate precursor) to be purified to less than 2.1, the alkylene oxide addition product with a high addition mole number, which is the cause of the formation of the emulsion layer, It has been found that the ratio of oxide adducts can be suppressed, the aqueous layer and the organic layer can be separated satisfactorily, and thereby the coloring-inducing substances can be efficiently removed. As for (b), the alkylene oxide adduct (secondary alcohol alkoxylate precursor) to be purified has a hydrogen bond between the alkylene oxide moiety and water, and is dissolved in water. When the mixture of the alkylene oxide adduct and water is allowed to stand to separate the organic layer and the aqueous layer, the standing temperature is set to more than 60° C., so that the thermal motion becomes vigorous, and the molecules of the alkylene oxide and water. The hydrogen bond between them is broken, and the water solubility of the alkylene oxide adduct is reduced. It was presumed that the aqueous layer and the organic layer could be satisfactorily separated from each other by this method, and the coloration-inducing substances could be efficiently removed. In addition, in order to remove the acid catalyst used in the production of secondary alcohol alkoxylates such as secondary alcohol ethoxylates, a mixed solution (alkaline aqueous solution) of water and a base (especially sodium hydroxide, potassium hydroxide) is used for cleaning (alkaline cleaning step). If the water washing treatment after the alkali washing step is insufficient, sodium fluoride (NaF) or sodium borohydride (e.g., NaH ₂ BO ₃ , NaHBO ₃ ) or the like is removed in the subsequent dehydration treatment step. Fine crystals may precipitate. However, by suppressing the formation of the emulsified layer as described above, these crystals can be efficiently removed, and the quality of the final product can be stabilized and improved.

It should be noted that the mechanism by which the above effects are exhibited by the configuration of the present invention is speculation, and the present invention is not limited to the above speculation.

Each step of the first aspect will be described below with reference to the drawings. In addition, the following description shows an example of each step of the first aspect, and the present invention is not limited to the following.

(Step (i))
In this step, a secondary alcohol is reacted with an alkylene oxide in the presence of a catalyst to obtain a reaction solution containing an alkylene oxide adduct (“first alkoxylation reaction” in FIG. 1).

The secondary alcohol, which is a raw material in the alkylene oxide addition reaction, is a saturated aliphatic hydrocarbon (normal paraffin) having 11 to 15 carbon atoms represented by the following formula (3), and a hydroxyl group is bonded to a carbon other than the terminal. is a mixture of secondary alcohols.

In the above formula (3), the sum of x and y (x+y) is an integer of 8-12.

The secondary alcohol is a secondary alcohol in which a hydroxyl group is bonded to a carbon other than the terminal of a saturated aliphatic hydrocarbon having 11 to 15 carbon atoms (x + y is an integer of 8 to 12). secondary alcohol) as a main component (hereinafter also simply referred to as "secondary alcohol"), preferably a saturated aliphatic hydrocarbon having 12 to 14 carbon atoms with a hydroxyl group bonded to a carbon other than the terminal. It is a mixture containing as a main component a secondary alcohol (the secondary alcohol of the above formula (3) in which x + y is an integer of 9 to 11). Here, "comprising a secondary alcohol as a main component" means that the secondary alcohol having a predetermined carbon number is more than 90% by mass (preferably more than 95% by mass) with respect to the secondary alcohol (upper limit: 100 % by mass). Further, the average molecular weight of the secondary alcohol is 158 or more and 228 or less, preferably 186 or more and 214 or less. Secondary alcohols may be synthetic or commercially available.

In one embodiment of the present invention, methods for producing a mixture of secondary alcohols represented by the above formula (3) include, for example, JP-A-48-34807, JP-A-56-131531, and JP-B-48. A known method such as JP-A-37242 can be applied in the same manner or with appropriate modifications. For example, a secondary alcohol is obtained by liquid phase oxidation of a saturated aliphatic hydrocarbon with a molecular oxygen-containing gas in the presence of metaboric acid to obtain a reaction liquid containing an oxide; obtaining a reaction liquid containing a compound; distilling the reaction liquid containing the borate compound to separate unreacted saturated aliphatic hydrocarbons and a distillation residue; hydrolyzing the distillation residue to hydrolyze orthoboric acid and an organic the organic layer is saponified with an alkali to separate into an alkaline aqueous solution layer and a crude alcohol layer; and the crude alcohol layer is purified.

In one aspect of the present invention, the alkylene oxide addition reaction includes, for example, JP-A-2003-221593, JP-A-48-34807, JP-A-56-131531, Oil Chemistry, 24, 7, p . p. 427-434 (1975), Japanese Patent Publication No. 51-046084, etc. can be applied in the same manner or with appropriate modifications. An example of the alkylene oxide addition reaction is shown below. In addition, this invention is not limited by the following method.

As the catalyst, an acid catalyst is used from the viewpoint that the number of moles of alkylene oxide to be added can be controlled low. Thus, in a preferred form of the invention, the catalyst is an acid catalyst. Acid catalysts include boron trifluoride, boron trifluoride-complex (etherate, phenolate, acetate complex, etc.), antimony pentachloride, tin tetrachloride, tris(pentafluorophenyl)borane, Examples include, but are not limited to, phosphoric acid, sulfuric acid, and the like. The amount of the catalyst to be added is 0.05 to 0.5 mass %, preferably more than 0.05 mass % and less than 0.3 mass % with respect to the secondary alcohol, but is not limited thereto.

As the alkylene oxide (AO), ethylene oxide, propylene oxide and the like are suitable. In one embodiment of the present invention, nitrogen substitution may be carried out when the alkylene oxide is added. The initial nitrogen pressure during nitrogen substitution is preferably 0.05 to 1.0 MPa, more preferably 0.05 to 0.4 MPa.

The amount of alkylene oxide supplied can be appropriately adjusted so that the average number of moles of alkylene oxide added to the secondary alcohol is less than 2.1. For example, the amount of alkylene oxide added is 1.0 mol or more and less than 1.8 mol, preferably more than 1.0 mol and 1.7 mol or less, more preferably 1.1 mol or less per 1 mol of the secondary alcohol. more than 1.5 moles, such as but not limited to. When the alkylene oxide is added in divided portions, the amount of alkylene oxide added is the total amount of alkylene oxide added.

The reaction between the secondary alcohol and the alkylene oxide is performed by supplying the secondary alcohol and the catalyst to the reactor, and then supplying the alkylene oxide to the reactor; after supplying the secondary alcohol to the reactor, the catalyst and The alkylene oxide may be fed to the reactor in any order; the secondary alcohol, alkylene oxide and catalyst may be fed to the reactor. Preferably, the alkylene oxide is fed after the secondary alcohol and catalyst are fed to the reactor. Further, the secondary alcohol, the catalyst and the alkylene oxide may be supplied all at once, continuously, or stepwise (dividedly). Preferably, the secondary alcohol and catalyst are fed to the reactor all at once, and the alkylene oxide is fed to the reactor stepwise (dividedly). This makes it possible to easily control the number of moles of alkylene oxide to be added (that is, n in formula (1)) within a desired range.

The reactor used for the reaction of the secondary alcohol and the alkylene oxide may be a tank reactor (batch reactor), a tubular reactor (continuous reactor), or a continuous tank reactor. . Also, the above reactors may be combined as appropriate. From the viewpoint that the alkylene oxide can be easily divided and supplied to the reactor, it is preferable to use at least a tubular reactor (continuous reactor). That is, in a preferred embodiment of the present invention, the secondary alcohol and alkylene oxide are reacted in a tubular reactor (continuous reactor), and alkylene oxide is added to at least one place other than the inlet of the tubular reactor. (that is, the alkylene oxide is divided and supplied). This makes it possible to more easily control the number of moles of alkylene oxide added (that is, n in formula (1)). In addition, with this configuration, temperature changes in the reactor can be suppressed, and local temperature rise due to ethylene oxide addition reaction can be suppressed/prevented. More preferably, a tubular reactor and a tank reactor are used in combination, and the tank reactor is installed downstream of the tubular reactor (the reactant of the tubular reactor is supplied to the tank reactor). is particularly preferred. With this configuration, the number of moles of alkylene oxide added (that is, n in formula (1)) can be more easily controlled while more effectively suppressing/preventing a local temperature rise due to the alkylene oxide addition reaction.

The shape/size of the reactor is not particularly limited, and can be appropriately selected according to the supply amount of each raw material (secondary alcohol, alkylene oxide, catalyst). For example, in a tubular reactor, the reactor (reaction tube) may be straight or partially curved (e.g., J-shaped, U-shaped, Z-shaped, etc.), It may be circular. The tubular reactor (reaction tube) preferably has at least a partial bend, and more preferably has a structure in which U-shaped reaction tubes are repeatedly connected as shown in FIG.

Also, the alkylene oxide may be supplied to multiple locations in the reactor, preferably the alkylene oxide is supplied to multiple locations in the tubular reactor. When a plurality of alkylene oxide supply units are installed in a reactor (especially a tubular reactor), the amount of alkylene oxide supplied in each supply unit is preferably an amount or reaction temperature that does not locally increase the reaction temperature. Preferably, the amount is such that it is controlled within a range. Alternatively, the alkylene oxide supply location is preferably a location where the alkylene oxide supplied in the preceding stage (upstream) reacts and the concentration of the alkylene oxide becomes low, but is not limited thereto. By controlling the reaction temperature within an appropriate range (especially 70° C. or lower) by supplying the alkylene oxide as described above in divided portions, the reduction in hue can be effectively suppressed.

In addition, in a tubular reactor, a thermometer (“TI” in FIG. 3) may be installed in only one place, but multiple thermometers are installed in the reactor to capture the peak temperature in the reactor. preferably installed. With this configuration, it is possible to evenly check the temperature change during the reaction. Here, the number of thermometers installed is preferably greater than or equal to the number of alkylene oxide supply points to the reactor so that the peak temperature in the reactor can be captured, for example, 5 or more and 50 or less, preferably 7 or more and 15 or less. but not limited to these. In addition, the installation interval of the thermometers is immediately after the alkylene oxide supply location to the reactor (for example, 0 m or more and less than 100 m, preferably 0 to 80 m from the alkylene oxide supply location, more preferably the total number of thermometers installed. At a rate of more than 80%, it is preferable to install it at a place where the temperature rises due to the reaction at 0 to 50 m) and the peak temperature can be caught, and is 1 m or more and 50 m or less, preferably 5 m or more and 10 m or less, but not limited to these. . By installing the thermometer as described above, it is possible to control the reaction temperature within an appropriate range (especially 70° C. or lower) and effectively suppress the decrease in hue.

As the reaction conditions (alkoxylation reaction conditions) between the secondary alcohol and the alkylene oxide, the same conditions as known can be employed. For example, the reaction temperature is 30° C. or higher and 70° C. or lower, preferably 45° C. or higher and 70° C. or lower, but is not limited thereto. In order to adjust the reaction temperature, the reactor may have a system for flowing a heating medium (eg hot water) as shown in FIG. As for the reaction temperature of the tubular reactor, it is preferable to monitor all the installed thermometers to check whether the peak temperature has exceeded. The reaction time is 30 minutes or more and 150 minutes or less, preferably 50 minutes or more and 120 minutes or less, but is not limited thereto. Under such conditions, the alkylene oxide addition mole (n in formula (1)) of the secondary alcohol alkoxylate precursor can be easily controlled to less than 2.1 in the next step (ii). Moreover, the by-production of coloring-inducing substances can be effectively suppressed/prevented. The above reaction time is the total reaction time when two or more reactors are used. Alternatively, the number of alkylene oxide additions of the alkylene oxide adduct during the reaction is measured, and the reaction may be terminated when the desired value is reached. The reaction pressure may be normal pressure or increased pressure, but from the viewpoint of solubility of alkylene oxide, reaction rate, etc., it is preferable to carry out the reaction under increased pressure using an inert gas such as nitrogen gas.

An alkylene oxide adduct (reaction solution containing an alkylene oxide adduct) is obtained by the above reaction. In addition, in the washing process of the following process (ii), the alkylene oxide addition reaction does not substantially proceed. Therefore, when only washing is performed in the washing step of step (ii), the alkylene oxide addition mole of the alkylene oxide adduct obtained in this step is a secondary alcohol alkoxylate represented by the following formula (1) It is substantially the same as the alkylene oxide addition mole (n in formula (1)) of the precursor. In an embodiment of the present invention, the alkylene oxide addition mole of the alkylene oxide adduct obtained in this step is 1.0 mol or more and less than 1.8 mol, preferably more than 1.0 mol and 1.7 mol or less, more preferably is more than 1.1 mol and less than 1.5 mol.

(Step (ii))
In this step, the reaction solution containing the alkylene oxide adduct obtained in step (i) above (hereinafter also simply referred to as “reaction solution”) is mixed with water, and then allowed to stand at a temperature exceeding 60° C. to obtain water. By separating into a layer and an organic layer, a liquid containing a secondary alcohol alkoxylate precursor represented by the formula (1): C _m H _2m+1 [O(XO) _n H] is obtained (“Reaction liquid washing” in FIG. 1). ). By adjusting the number of moles of alkylene oxide added (average number of moles added) to less than 2.1, the formation of an emulsified layer between the aqueous layer and the organic layer is well suppressed and prevented, and the aqueous layer and the organic layer are separated. can be separated well. Here, the catalyst (especially the acid catalyst) that causes the coloring, and reaction by-products (coloring-inducing substances) such as polyethylene glycol and dioxane move to the aqueous layer. Therefore, according to this step, the aqueous layer containing the coloration-inducing substance can be efficiently separated from the organic layer (the coloration-inducing substance can be efficiently removed). On the other hand, when the number of moles of alkylene oxide added (n in formula (1)) is 2.1 or more, foaming occurs when mixed with water, and an emulsified layer is formed between the aqueous layer and the organic layer. Poor separation of layers and organic layers. As a result, the coloring-inducing substance contained in the water layer cannot be removed, and the hue of the final product (secondary alcohol alkoxylate) is lowered (Comparative Example 1 below).

In the above formula (1), X represents an alkylene group having 1 to 3 carbon atoms. Here, the alkylene group having 1 to ₃ carbon atoms is a methylene group ₍ --CH.sub.2--), an ethylene group ₍ --CH.sub.2CH.sub.2--), a trimethylene group _{( --CH.sub.2CH.sub.2CH.sub.2--} ), a propylene group ₍ -- CH(CH ₃ )CH ₂ —, —CH ₂ CH(CH ₃ )—). Preferably X is an ethylene group. m is the number of carbon atoms in the secondary alcohol alkoxylate precursor. m is 11-15, preferably 12-14. n is the average number of added moles of alkylene oxide in the alkylene oxide adduct. n is greater than 0 and less than 2.1, preferably less than 2.0, more preferably less than 1.8, particularly preferably less than 1.7. Here, when n is 2.1 or more, micelles are generated when mixed with water in this step (ii), and an emulsified layer is formed between the aqueous layer and the organic layer. and the organic layer are difficult to separate, resulting in insufficient removal of color-inducing substances (eg, catalysts, reaction by-products such as polyethylene glycol and dioxane). The lower limit of n is more than 0, preferably 1.2 or more, more preferably more than 1.5, from the viewpoint of improving the yield of the target product (especially secondary alcohol alkoxylate 3-mol adduct). . That is, in a preferred embodiment of the present invention, n is 1.2 or more and less than 2.0 in the above formula (1). In a more preferred form of the present invention, n is more than 1.5 and less than 1.8 in the above formula (1). In a particularly preferred form of the present invention, n is more than 1.5 and less than 1.7 in the above formula (1). In the present specification, the value measured by the following method is adopted as the average number of added moles of alkylene oxide.

(Average addition mole number of alkylene oxide of alkylene oxide adduct)
The average number of added moles of alkylene oxide (average number of added moles of AO) of the alkylene oxide adduct is calculated using the following formula 1 from the analytical value of the hydroxyl value of the alkylene oxide adduct. Incidentally, the hydroxyl value is measured based on the B method of JIS K1557-1:2007. Specifically, a pyridine solution containing phthalic anhydride is used as a sample, and hydroxyl groups are phthalated under pyridine reflux. Excess phthalating reagent is hydrolyzed with water and the phthalic acid produced is titrated with standard sodium hydroxide solution. The hydroxyl value is determined by calculating from the titer difference between the blank test and the sample test.

The alkylene oxide adduct may be mixed with water alone or mixed with a solution containing water (hereinafter also referred to as "wash water"). Here, in the case of using washing water, the washing water contains, in addition to water, bases such as sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, lithium hydroxide, etc., magnesium hydroxide, etc. It is not limited to these. Preferably, the washing water is a mixed liquid (alkaline aqueous solution) of water and a base (particularly sodium hydroxide or potassium hydroxide). In addition, the content of the component such as the base in the washing water is, for example, such an amount that the concentration is 0.1 to 30% by mass, preferably 0.5 to 5% by mass, but is not limited thereto. Thereby, the catalyst (especially the acid catalyst) can be removed efficiently. Further, the step of mixing the alkylene oxide adduct with water or washing water may be carried out once or may be carried out repeatedly two or more times. In the latter case, the alkylene oxide adduct is mixed with washing water and separated into an aqueous layer and an organic layer (organic layer 1), and then this organic layer 1 is mixed with water alone to form an aqueous layer and an organic layer. (Organic layer 2) is preferably separated. That is, in a preferred embodiment of the present invention, the separation is performed by mixing a reaction solution containing an alkylene oxide adduct with an alkaline aqueous solution to separate into an aqueous layer and an organic layer 1, and then mixing the organic layer 1 with water to form an aqueous layer. and organic layer 2. As a result, the coloring-inducing substance can be removed more efficiently.

The mixing ratio of the alkylene oxide adduct and water or washing water (especially alkaline aqueous solution) (reaction solution containing alkylene oxide adduct: water or washing water (mixing volume ratio)) is preferably 1 to 8:1, more preferably. is 3 to 5:1, but is not limited thereto. That is, in a preferred embodiment of the present invention, when the reaction solution containing the alkylene oxide adduct is mixed with the aqueous alkali solution, the mixing volume ratio of the reaction solution and the aqueous alkali solution is 1 to 8:1. Further, in a preferred embodiment of the present invention, the mixing volume ratio of the organic layer 1 and water when mixing the organic layer 1 with water is 1 to 8:1. In a more preferred form of the present invention, when the reaction solution containing the alkylene oxide adduct is mixed with the aqueous alkali solution, the mixing volume ratio of the reaction solution and the aqueous alkali solution is 3 to 5:1. Further, in a more preferred embodiment of the present invention, the mixing volume ratio of the organic layer 1 and water when mixing the organic layer 1 with water is 3 to 5:1. As described above, by suppressing the amount of water or washing water to an amount equal to or less than that of the liquid containing the alkylene oxide adduct (reaction liquid or organic layer 1) (especially to a smaller amount), the washing efficiency is ensured while the reaction liquid is treated with water. Alternatively, the emulsified state (especially water-in-oil type) (and thus coloring) when mixed with washing water can be more effectively suppressed/prevented.

Moreover, the method for mixing the alkylene oxide adduct with water or washing water is not particularly limited, and a known method can be used. For example, water or washing water is added to the alkylene oxide adduct, sufficiently stirred and mixed to dissolve the alkylene oxide adduct in the organic layer, then allowed to stand, and when the aqueous layer and the organic layer are separated, the organic layer is taken out. methods and the like. Here, stirring/mixing conditions are not particularly limited. For example, the stirring/mixing temperature is 40 to 100°C, preferably 80 to 100°C. The stirring/mixing time is 5 to 120 minutes, preferably 10 minutes or more and less than 30 minutes. When the alkylene oxide adduct is washed with water and washing water (washing with water followed by washing with washing water, or washing with washing water and then washing with water), the stirring and mixing conditions in each washing step may be the same. or may be different.

After the reaction solution is mixed with water or washing water, it is allowed to stand at a temperature above 60° C. to separate into an aqueous layer and an organic layer. Here, if the stationary temperature is 60° C. or less, an emulsified layer is formed between the aqueous layer and the organic layer, and the aqueous layer cannot be separated well. As a result, the coloring-inducing substance contained in the water layer cannot be removed, and the hue of the final product (secondary alcohol alkoxylate) is lowered (Comparative Example 2 below). The standing temperature is preferably above 60°C and below 100°C, more preferably above 60°C and below 95°C, and particularly preferably above 65°C and below 85°C. The standing time is, for example, 5 to 120 minutes, preferably 30 to 60 minutes, but is not limited to the above. When the alkylene oxide adduct is washed with water and washing water (water washing followed by washing water washing, or washing water washing followed by water washing), the stationary temperature in each washing step may be the same or They may be different, but both have a standing temperature above 60°C. Therefore, in a preferred embodiment of the present invention, the separation is carried out by mixing a reaction solution containing an alkylene oxide adduct with an aqueous alkali solution, allowing the mixture to stand at a temperature exceeding 60°C to separate the aqueous layer and the organic layer 1, and then Organic layer 1 is mixed with water and allowed to stand at a temperature above 60° C. to separate into aqueous and organic layers 2 . Similarly, when the alkylene oxide adduct is washed with water and washing water (washing with water followed by washing with washing water, or washing with washing water and then washing with water), the standing time in each washing step should be the same. or different.

The device used for mixing the alkylene oxide adduct with water or washing water is not particularly limited, but as shown in FIG. After stirring and mixing water), a mixer/settler type apparatus can be used in which the water layer and the organic layer can be separated in the settler part (static tank). Alternatively, an apparatus such as a line mixer or a countercurrent washing tower may be used.

The organic layer obtained above may be dehydrated if necessary. Thereby, the number of moles of alkylene oxide added to the secondary alcohol alkoxylate precursor (n in formula (1)) can be more effectively controlled within a desired range. Here, the dehydration method is not particularly limited, and a known method can be applied in the same manner or by appropriately modifying it. For example, the organic layer can be dehydrated by distillation or fractional distillation. The dehydration pressure (top pressure) at this time is 1 to 500 hPa, preferably 50 to 300 hPa, etc., but is not limited thereto. In the present specification, the pressure means the value of pressure measured by a pressure gauge installed at the top of the reactor to measure the pressure of the gas phase. All the same definitions apply throughout this specification unless otherwise specified. The dehydration temperature (bottom temperature) is 50 to 200° C., preferably 100 to 150° C., but is not limited thereto. Under such conditions, unreacted alcohol and the like are efficiently removed, and the number of moles of alkylene oxide added to the secondary alcohol alkoxylate precursor (n in formula (1)) is further reduced to the desired range. controllable.

As described above, a liquid containing a secondary alcohol alkoxylate precursor having a desired number of moles of alkylene oxide added at high purity is obtained.

(Step (iii))
In this step, the liquid containing the secondary alcohol alkoxylate precursor separated in the above step (ii) is purified (“light separation” and “rectification” in FIG. 1). This gives a secondary alcohol alkoxylate of formula (2): C _m H _{2m +1} [O(XO) pH]. In formula (2) above, X and m have the same definitions as in formula (1) above. p is the average added mole number of the alkylene oxide of the secondary alcohol alkoxylate. p is 2.5 or more and 3.5 or less, preferably more than 2.7 and less than 3.1. In the present specification, the average number of added moles of alkylene oxide in the secondary alcohol alkoxylate employs a value measured by the same method as described for n in formula (1) above.

Here, the purification method is not particularly limited, and known methods can be applied in the same manner or by appropriately modifying them. For example, it can be purified by distillation or fractional distillation of a liquid containing a secondary alcohol alkoxylate precursor. The purification pressure (top pressure) at this time is 1 to 100 hPa, preferably 3 to 50 hPa, etc., but is not limited thereto. The purification temperature (bottom temperature) is 150 to 250° C., preferably 175 to 225° C., but not limited thereto. Under such conditions, light products, unreacted alcohols, secondary alcohol alkoxylate fractions with a low alkylene oxide addition mole number (for example, less than 2.5), etc. are efficiently removed, and the desired Secondary alcohol alkoxylates can be adequately separated. Although the purification process (distillation/fractionation process) is performed twice in FIG. 1, the purification process may be performed once or repeatedly. For example, as shown in FIG. 1, after removing the light matter in the light separation step (“light separation” in FIG. 1), the rectification step (“rectification” in FIG. 1) is performed to add unreacted alcohol or alkylene oxide. Low AO mole add-on fractions with low moles (eg, alkylene oxide add-on moles = less than 2.5) may be removed.

The above results in secondary alcohol alkoxylates of high purity (low or no color-inducing substances). Therefore, the secondary alcohol alkoxylate according to the present invention is excellent in hue. Specifically, the hue (APHA) of the secondary alcohol alkoxylate is less than 45. That is, the present invention has a hue (APHA) of less than 45, formula (2): C _m H _{2m +1} [O(XO) pH] (wherein X is an alkylene group having 1 to 3 carbon atoms, m is 12-14; p is 2.5-3.5) (second aspect). Here, the hue (APHA) of the secondary alcohol alkoxylate is preferably 40 or less, more preferably 30 or less. Here, the lower limit of the hue (APHA) of the secondary alcohol alkoxylate is not particularly limited, but 20 or more is sufficient. That is, the hue (APHA) of the secondary alcohol alkoxylate is preferably 20-40, more preferably 20-30. In this specification, the hue (APHA) of the secondary alcohol alkoxylate adopts the value measured by the method described in the examples below.

The secondary alcohol alkoxylate obtained above is, if necessary, further added with an alkylene oxide to increase the number of AO moles (secondary alcohol alkylene oxide high adduct ) may be produced (“second alkoxylation reaction” in FIG. 1). Preferably, a tubular reactor is used to carry out the second alkoxylation reaction under certain conditions as detailed below. Thereby, the secondary alcohol alkylene oxide high adduct with reduced coloring can be mass-produced.

That is, according to the present invention, the method of the present invention is used to obtain the formula (2): C _m H _{2m +1} [O(XO) pH] (wherein X represents an alkylene group having 1 to 3 carbon atoms, m is 12 to 14; p is 2.5 to 3.5),
Alkylene oxide is added to the secondary alcohol alkoxylate through alkylene oxide supply units installed at the inlet of the tubular reactor and n locations other than the inlet (n is an integer of 2 or more), The secondary alcohol alkoxylate is reacted with the alkylene oxide in the tubular reactor to form formula (4): C _m H _2m+1 [O(XO) _q H] (wherein X is carbon represents an alkylene group with a number of 1 to 3; m is 12 to 14; q is more than 3.5 and 50 or less).
The alkylene oxide supply unit is installed in the tubular reactor so as to satisfy the following formula (i), and further the alkylene oxide is added to the secondary alcohol alkoxylate so as to satisfy the following formula (ii). , also provides a method (third aspect) for the preparation of secondary alcohol alkylene oxide high adducts:

The second alkoxylation reaction according to the preferred embodiment (third aspect) will be described below with reference to the drawings. In addition, the following description shows an example of the second alkoxylation reaction step, and the present invention is not limited to the following.

In the preferred embodiment (third aspect), when the alkylene oxide is dividedly supplied (divided feed) to the secondary alcohol alkoxylate in a plurality of supply units in a tubular reactor (reaction tube), ( _i ) The _alkylene and (ii) satisfy formula (ii): N[Y _n″ , Y _n″+1 ]/n≧0.3, that is, so that the amount supplied increases at a rate of 30% or more, Alkylene oxide is supplied to produce a secondary alcohol alkylene oxide high adduct having a high alkylene oxide addition mole number, which is the final product. This particular form of split feed allows for better control of the alkylene oxide addition reaction and, as a result, further reduces the coloration of the final secondary alcohol alkylene oxide high adduct. Moreover, the method according to this embodiment is a continuous production method. Therefore, it is possible to mass-produce secondary alcohol alkylene oxide high adducts with reduced coloring. Therefore, according to the above configuration, the secondary alcohol alkylene oxide high adduct with reduced coloring can be mass-produced. In addition, the mechanism of exhibiting the said effect by the structure of this invention is speculation, and this invention is not limited to the said speculation.

In the present preferred embodiment (third aspect), the tubular reactor has alkylene oxide feeders at the inlet and n locations other than the inlet (n is an integer of 2 or more), and these alkylene oxide feeders Alkylene oxide is added to the secondary alcohol alkoxylate via a section (divided supply), and the secondary alcohol alkoxylate is reacted with the alkylene oxide in the tubular reactor. In this specification, the alkylene oxide supply part intends a supply part to which alkylene oxide is actually supplied. Therefore, even if it is installed in a tubular reactor to supply alkylene oxide, an alkylene oxide supply unit that does not actually supply alkylene oxide is not regarded as an "alkylene oxide supply unit."

In this preferred embodiment (third aspect), in the tubular reactor, the alkylene oxide supply section (including the reactor inlet) is installed in the tubular reactor so as to satisfy the following formula (i). That is, when the secondary alcohol alkoxylate and the alkylene oxide are reacted, the alkylene oxide supply set is installed at a rate exceeding 40%.

In formula (i) above, N[X _n′ , X _n′+1 ] represents the number of three adjacent alkylene oxide supplier sets satisfying X _n′ <X _n′+1 . At this time, _Xn' is the alkylene oxide supply part _Pn' installed at the n'th from the inlet side of the tubular reactor and the alkylene oxide supply part Pn' installed at the n'+1th from the inlet side of the tubular reactor. It represents the interval (m) between the supply part _Pn'+1 and the supply part Pn'+1. n' is an integer of 0 or more and n-2 or less. In addition, X _n′+1 is the distance (m) between the alkylene oxide supply unit P _n′+1 and the alkylene oxide supply unit P _n′+2 which is installed n′+2 from the inlet side of the tubular reactor. Represent. That is, N[X _n' , X _n'+1 ] is represented by three adjacent alkylene oxide feeds (P _n' , P _n'+1 and P _{n' +2} ) is set as one set, the distance (X _n' ) between the two adjacent alkylene oxide supply ports (P _n' and P _n'+1 ) on the inlet (reaction upstream) side is reduced to the outlet (reaction downstream) side. The interval (X n′+1 ) between two adjacent alkylene oxide supply units (P _n′+1 and P _n′+2 ) means the number of sets of alkylene oxide supply units where the interval (X _n′+1 ) is larger (X _n′ <X _n′+1 ) do.

That is, the above formula (i) is the number of alkylene oxide supplier sets (N[X _{n '} , X _{n ' +1} ]) ratio (N[X _n′ , X _n′+1 ]/(n−1)) is more than 40% (4/10). As used herein, “N[X _n′ , X _n′+1 ]/(n−1)” means the number of alkylene oxide supplier sets satisfying X _n′ <X _n′+1 (N[X _n′ , X _n′+1 ]) divided by the number of all alkylene oxide supply unit sets (n−1) is obtained to the second decimal place, rounded off to the first decimal place, and the value obtained is adopted.

In this preferred embodiment (third aspect), the reaction tube is intended to be a portion of the tubular reactor where the addition reaction of the alkylene oxide to the secondary alcohol alkoxylate substantially proceeds. For this reason, for example, in FIG. 4, the reaction tube portion between the tubular reactor inlet (P ₀ in FIG. 4) and the tubular reactor outlet (P _outlet in FIG. 4) is It is a reaction tube according to.

In this preferred embodiment (third aspect), the alkylene oxide supply (P _0′ ) where n′ is 0 is the first alkylene oxide supply installed in the reaction tube, the tubular reactor inlet (FIG. 4 "P ₀ " in the middle).

In this preferred form (third aspect), the spacing (X _n′ ) between two adjacent alkylene oxide feeds (P _n′ and P _n′+1 ) is such that the alkylene oxide feeds are The center of the reaction tube (“P _n′ ” in FIG. 5) in the alkylene oxide supply section (P _{n ′} ) where the The distance between (P _n′+1 ) and the center of the reaction tube (“P _n′+1 ” in FIG. 5) (the length of the solid line portion “X _n′ ” in FIG. 5). In this case, the center of the reaction tube is the center of gravity of the cut surface obtained by cutting the tube along a plane perpendicular to the longitudinal direction of the reaction tube. For example, if the cross section of the reaction tube is circular, it is the center of the circle, and if it is not circular, it is the center of the largest circle that can be drawn inside the cross section of the reaction tube. For example, the distance (X _1′ ) between the alkylene oxide supply portion (P _0′ ) and the alkylene oxide supply portion (P _1′ ) adjacent to the P _0′ is the reaction tube inlet ( It is the distance between the center of the reaction tube at the boundary between the center of the tube plate surface and the reaction tube) and the center of the reaction tube at the alkylene oxide supply section where the alkylene oxide is supplied next.

Here, when N[X _n′ , X _n′+1 ]/(n−1) in formula (i) is 0.4 or less, the alkylene oxide is supplied too frequently, and the alkylene oxide is secondary It may be locally added to the alcohol alkoxylate, resulting in coloration of the secondary alcohol alkylene oxide high adduct as the final product. From the viewpoint of further reducing the coloration of the secondary alcohol alkylene oxide high adduct as the final product, N[X _n' , X _n'+1 ]/(n-1) in formula (i) is 0. It is preferably 5 or greater, more preferably greater than 0.7, and particularly preferably 0.8 or greater. According to this embodiment, the local addition reaction of the alkylene oxide to the secondary alcohol alkoxylate is suppressed, the alkylene oxide addition reaction is appropriately controlled, and the secondary alcohol alkylene oxide high adduct as the final product is obtained. Coloring can be reduced more effectively. Since it is preferable to satisfy X _n' <X _n'+1 in all alkylene oxide supply part sets, the upper limit of N[X _n' , X _n'+1 ]/(n-1) in formula (i) is It is preferably 1, but may be, for example, less than 0.95 or 0.9 or less.

In the present preferred embodiment (third aspect), as in the above formula (i), the alkylene oxide is supplied at a rate of more than 40% so that the supply interval is long, but preferably at a rate of more than 80%, more Preferably, in all the alkylene oxide supply unit sets, the alkylene oxide supply interval is equal to or greater than (X _n' ≤ X _n'+1 ). With this configuration, the coloring of the secondary alcohol alkylene oxide high adduct, which is the final product, can be more effectively reduced.

In this preferred embodiment (third aspect), when X _n′+1 is greater than X n _′ (X _n′ <X _n′+1 is satisfied), the With respect to the distance [X _n'+1 (m)] between the alkylene oxide supply unit P _n'+1 and the alkylene oxide supply unit P _n'+2 installed n'+2 from the inlet side of the tubular reactor, an alkylene oxide supply unit P _n′ installed at the n′-th position from the inlet side of the tubular reactor, an alkylene oxide supply unit P _n′+1 installed at the n′+1-th position from the inlet side of the tubular reactor; The ratio [X _n′+1 /X _n′ ] of the spacings [X _n′ (m)] of is greater than one. From the viewpoint of further reducing the coloring of the secondary alcohol alkylene oxide high adduct as the final product, the ratio of X _n' to X n' ₊ 1 [X _n'+1 /X _n' ] is preferably 1. 05, more preferably 1.10 or more, but not limited thereto. In the above case, the ratio of X _n' to X n' ₊ 1 [X _n'+1 /X _n' ] is, for example, 1.50 or less, preferably less than 1.30, but is not limited thereto. .

In the present preferred embodiment (third aspect), the alkylene oxide supply interval (distance between adjacent alkylene oxide supply portions, “X _n′ ” in FIG. 5) is, for example, 10 m or more and 200 m or less, preferably 20 m or more. 150 m or less, more preferably over 30 m and less than 100 m, but not limited thereto. Local addition reaction of the alkylene oxide to the secondary alcohol alkoxylate can be suppressed/prevented more effectively. Therefore, the hue of the secondary alcohol alkylene oxide high adduct, which is the final product, can be improved.

In this preferred embodiment (third aspect), the number of alkylene oxide supply units installed in the tubular reactor is installed so as to decrease in the downstream direction of the tubular reactor. Preferably, the alkylene oxide feed between the inlet of the tubular reactor and half the total tube length for the number of alkylene oxide feeds installed between more than half the total tube length of the tubular reactor and the outlet (N _outlet ) The ratio (N _inlet /N _outlet ) of the number of installed portions (N _inlet ) is more than 1.0/1 and 10.0/1 or less, preferably 1.5/1 or more and less than 5.0/1. As used herein, "N _inlet " means the area from the inlet to half the total tube length (including the reactor inlet and half the total tube length) in the total tube length from the inlet to the outlet of a tubular reactor ("tubular is the number of alkylene oxide feeds installed in the "reactor upstream zone"). Thus, when alkylene oxide feeds are located at the tubular reactor inlet, the "N _inlet " includes the number of ethylene oxide feeds located at the tubular reactor inlet. In addition, “N _outlet ” is the region extending from the tube reactor inlet to the outlet to the outlet beyond half of the total tube length of the tubular reactor (also referred to as “tubular reactor downstream region”). is the number of alkylene oxide supply units installed. "N _inlet /N _outlet " employs a value obtained by dividing the above "N _inlet " by the above "N _outlet " to the second decimal place and then rounding to the first decimal place. For example, in Example 1 below, a total of 10 ethylene oxide supply units including the second reactor inlet are installed in the second reactor, and the area from the inlet of the second reactor to half the total tube length (tubular reaction The number of alkylene oxide supply units installed in the upstream region of the reactor) is 8 (N _inlet =8), and the region from the outlet of the tubular reactor of the second reactor beyond half the total tube length (downstream of the tubular reactor) area) is 2 (N _outlet =2), N _inlet /N _outlet is 4.0 (=8/2).

In this preferred embodiment (third aspect), an alkylene oxide is added to the secondary alcohol alkoxylate in a tubular reactor so as to satisfy the following formula (ii). That is, when the secondary alcohol alkoxylate and the alkylene oxide are reacted, the alkylene oxide is supplied at a ratio of 30% or more so that the supply amount increases.

In formula (ii) above, N[Y _n″ , Y _n″+1 ] represents the number of two adjacent alkylene oxide supplier sets satisfying Y _n″ <Y _n″+1 . At this time, Y _n″ represents the supply amount (kg/hr) of alkylene oxide in the alkylene oxide supply part P _n″ installed n″ from the inlet side of the tubular reactor. n″ is 0 or more n. It is an integer less than or equal to -1. In addition, Y _n″+1 represents the supply amount (kg/hr) of alkylene oxide in the alkylene oxide supply part P _n″+1 which is installed n″+1 from the inlet side of the tubular reactor. That is, N[ Y _n″ , Y _n″+1 ] is an alkylene oxide supply portion on the inlet (reaction upstream) side when two adjacent alkylene oxide supply portions (P _n″ and P _n″+1 from the inlet side) are regarded as one set. The amount of alkylene oxide supplied (Y _{n″ )} at the alkylene oxide supply portion (P _{n″+1 )} adjacent to the exit (downstream of the reaction) on the outlet side (reaction downstream side) is calculated as follows: The larger (Y _n″ <Y _n″+1 ) means the number of alkylene oxide supplier sets.

That is, the above formula (ii) is the number of alkylene oxide supply unit sets (N[Y _n″ , Y _n″+1 ]) that satisfies Y _n″ <Y _n″+1 with respect to all the number of alkylene oxide supply unit sets (n). is 30% (3/10) or more. As used herein, “N[Y _n″ , Y _n″+1 ]/n” is the number of alkylene oxide supplier sets satisfying Y _n″ <Y _n″+1 (N[Y _n″ , Y _n″+1 ] ) is divided by the number of all alkylene oxide supply unit sets (n) to the second decimal place, and the value obtained by rounding to the first decimal place is employed.

In this preferred embodiment, the alkylene oxide supply section (P _0″ ) where n″ is 0 is the tubular reactor inlet (“P ₀ ” in FIG. 4), which is the alkylene oxide supply section installed first in the reaction tube. ).

Here, when N[Y _n″ , Y _n″+1 ]/(n−1) in formula (ii) is less than 0.3, the temperature rise in the reactor appropriately controls the alkylene oxide addition reaction. As a result, the secondary alcohol alkylene oxide high adduct, which is the final product, may be colored. From the viewpoint of further reducing the coloration of the secondary alcohol alkylene oxide high adduct, which is the final product, N[Y _n″ , Y _n″+1 ]/(n-1) in formula (ii) is 0. It is preferably 6 or more, more preferably over 0.7, and particularly preferably 0.9 or more. The upper limit of N[Y _n″ , Y _n″+1 ]/(n−1) in formula (ii) is preferably 1. For example, even if it is less than 0.97 or 0.95 or less, good.

In the present preferred embodiment (third aspect), the alkylene oxide is supplied at a rate of 30% or more so that the amount of alkylene oxide supplied increases, as according to the above formula (ii), but preferably the rate exceeds 80%. More preferably, 90% or more of the alkylene oxide supply unit set has the same or more supply amount of alkylene oxide (Y _n″ ≦Y _n″+1 ). With this configuration, the coloring of the secondary alcohol alkylene oxide high adduct, which is the final product, can be more effectively reduced.

In the present preferred embodiment (third aspect), when Y _n″+1 is greater than Y n _″ (Y _n″ <Y _n″+1 ), at the inlet (reaction upstream) side alkylene oxide supply section (P _n″ ) The difference between the alkylene oxide supply amount (Y _n″ ) of the outlet (reaction downstream) side and the alkylene oxide supply amount (Y _n″+1 ) at the adjacent alkylene oxide supply portion (P _n″+1 ) on the side of the outlet (downstream of the reaction) (Y _{n "+1} - Yn _" (kg/hr)) is greater than 0 (kg/hr). From the viewpoint of further reducing the coloring of the secondary alcohol alkylene oxide high adduct, which is the final product, when Y _n″+1 is greater than Y n _″ (Y _n″ <Y _n″+1 ), Y _n″ and Y _n″+1 , the difference (Y _n″+1 −Y _n″ (kg/hr)) is preferably 0.5 (kg/hr) or more and 60 (kg/hr) or less, more preferably 1 (kg/hr) or more and less than 40 (kg/hr), but not limited thereto.

In this preferred form (third aspect), the second alkoxylation reaction is carried out in a tubular reactor, under conditions as described above, at the inlet of the tubular reactor and at least one place other than said inlet, the alkylene oxide is is added to react the secondary alcohol alkoxylate with the alkylene oxide sequentially. With this configuration, it is possible to suppress local temperature changes in the reactor (in particular, suppress/prevent local temperature increases due to alkylene oxide addition reactions). Therefore, the coloring of the secondary alcohol alkylene oxide high adduct, which is the final product, can be effectively reduced. It is also possible to easily control the added mole number of alkylene oxide in the secondary alcohol alkylene oxide high adduct, which is the final product. The reaction between the secondary alcohol alkoxylate and the alkylene oxide may be carried out in a tubular reactor (continuous reactor). A type reactor (continuous reactor) or a continuous tank type reactor may be provided separately.

In one aspect of the present preferred embodiment (third aspect), the alkylene oxide addition reaction includes, for example, JP-A-2003-221593, JP-A-48-34807, JP-A-56-131531, oil Chemistry, 24, 7, p. p. 427-434 (1975), Japanese Patent Publication No. 51-046084, etc. can be applied in the same manner or with appropriate modifications. An example of the alkylene oxide addition reaction is shown below. In addition, this invention is not limited by the following method.

In the present preferred embodiment (third aspect), the catalyst is from the viewpoint that a secondary alcohol alkylene oxide high adduct having a desired number of moles of alkylene oxide to be added can be produced (the number of moles of alkylene oxide to be added can be controlled to be high). Alkaline catalysts are used from Thus, in a preferred form of the invention, the catalyst is an alkaline catalyst. Alkaline catalysts include, but are not limited to, sodium hydroxide, potassium hydroxide, sodium alkoxides, and the like. The amount of the catalyst to be added is 0.01 to 1 mass %, preferably more than 0.02 mass % and less than 0.5 mass % with respect to the secondary alcohol alkoxylate, but is not limited thereto. Alternatively, the feed rate of the catalyst to the tubular reactor is 0.1 to 5 kg/hr, preferably 0.5 to 2 kg/hr, but is not limited thereto. In this step, the catalyst may be added as it is or in the form of a solution (for example, an aqueous solution). The concentration of the catalyst in the latter case is about 30 to 70% by mass in the catalyst solution, but is not limited to this.

In the present preferred embodiment (third aspect), the alkylene oxide (AO) is preferably ethylene oxide, propylene oxide, or the like. In one embodiment of the present invention, nitrogen substitution may be carried out when the alkylene oxide is added. The initial nitrogen pressure during nitrogen substitution is preferably 1.0 to 2.0 MPa, more preferably 1.3 to 1.7 MPa.

In this preferred embodiment (third aspect), the feed rate of alkylene oxide to the tubular reactor is 300-1500 kg/hr, preferably 700-1200 kg/hr, but is not limited thereto. Alternatively, the amount of alkylene oxide supplied to the tubular reactor is the average number of moles of alkylene oxide added to the secondary alcohol (average number of moles of alkylene oxide added in the secondary alcohol alkylene oxide high adduct as the final product ) is 5 to 50 mol (preferably 6 to 15 mol, more preferably 7 to 9 mol). For example, the amount of alkylene oxide added is 5 to 15 mol, preferably 6 to 12 mol, per 1 mol of the secondary alcohol alkoxylate, but is not limited thereto. The amount of alkylene oxide added is the total amount of alkylene oxide added in this step.

In this preferred embodiment (third aspect), the reaction of the secondary alcohol alkoxylate and the alkylene oxide is carried out by feeding the secondary alcohol alkoxylate and the catalyst to the reactor and then dividing the alkylene oxide into tubular reactors. feeding; secondary alcohol alkoxylate and catalyst in either order (secondary alcohol alkoxylate post-catalyst or post-catalyst secondary alcohol alkoxylate) or simultaneously into the tubular reactor; feeding the alkylene oxide into the reactor in portions; after feeding the secondary alcohol alkoxylate, the alkylene oxide and the catalyst into the tubular reactor, then feeding the alkylene oxide at at least one point other than the reactor inlet; can be done in the form of Preferably, after the secondary alcohol alkoxylate, alkylene oxide and catalyst are fed to the tubular reactor, the alkylene oxide is fed at least one location other than the reactor inlet under the specific conditions described above. This makes it possible to more effectively suppress local temperature changes in the reactor (particularly, more effectively suppress/prevent local temperature increases due to alkylene oxide addition reactions). Therefore, the coloring of the secondary alcohol alkylene oxide high adduct, which is the final product, can be more effectively reduced. In addition, the added mole number of the alkylene oxide in the secondary alcohol alkylene oxide high adduct, which is the final product, can be more easily controlled. The secondary alcohol and catalyst may each be fed all at once, continuously, or stepwise (divided).

In this preferred embodiment, the shape and size of the tubular reactor are not particularly limited, and can be appropriately selected according to the supply amount of each raw material (secondary alcohol alkoxylate, alkylene oxide, catalyst). For example, a tubular reactor (reaction tube) may be linear, partially curved (e.g., J-shaped, U-shaped, Z-shaped, helical, etc.), or circular. may be The tubular reactor (reaction tube) preferably has at least a partial bend, more preferably has a U-shaped reaction tube, and particularly preferably has a U-shaped reaction tube as shown in FIG. It has a structure in which reaction tubes are repeatedly connected. That is, in a preferred form of the invention, the tubular reactor has at least a partial bend. In a preferred form of the invention, the tubular reactor has a U-shaped reaction tube. In a particularly preferred form of the present invention, the tubular reactor has a structure in which U-shaped reaction tubes are repeatedly connected.

In this preferred embodiment (third aspect), the inner diameter of the tubular reactor (reaction tube) is 15 mm or more and 65 mm or less, preferably 20 mm or more and 50 mm or less, but is not limited thereto. The outer diameter of the tubular reactor (reaction tube) is 10 mm or more and 70 mm or less, preferably 25 mm or more and 55 mm or less, but is not limited thereto. The length (tube length, overall length) of the tubular reactor (reaction tube) can be appropriately selected according to the production amount of the secondary alcohol alkylene oxide high adduct. For example, the length (tube length) of the tubular reactor (reaction tube) is 100 m or more and 3000 m or less, preferably more than 300 m and 2000 m or less, but is not limited thereto. With a tubular reactor of such size, the color of the secondary alcohol alkylene oxide high adduct, which is the final product, can be more effectively improved.

In this preferred embodiment (third aspect), the alkylene oxide is supplied at least one location other than the inlet of the tubular reactor (via a supply section installed along the longitudinal direction of the tubular reactor successively introduced). Here, the number of alkylene oxides to be supplied per 1,000 m of tubular reactor length is set at, for example, 2 or more and 30 or less, preferably 3 or more and 20 or less, more preferably 5 or more and 18 or less, other than the inlet of the reactor. , but not limited to. That is, in one form of the present invention, alkylene oxide is added at 2 to 30 locations per 1000 m of tubular reactor. In a preferred form of the invention, the alkylene oxide is added at 3 to 20 locations per 1000 m of tubular reactor. In a more preferred form of the invention, the alkylene oxide is added at 5 to 18 locations per 1000 m of tubular reactor. Here, the alkylene oxide supply unit may be installed at any position in the tubular reactor, but is preferably installed on the same tube plate surface of the tubular reactor as shown in FIG. With this configuration, the amount of alkylene oxide supplied can be controlled, and coloring can be reduced.

In this preferred embodiment (third aspect), each alkylene oxide supply section of the tubular reactor may be provided with a mechanism for smoothly supplying alkylene oxide. As such a mechanism, for example, a weir is provided on the surface of the supply section, a mechanism is provided for selectively circulating alkylene oxide from one reaction tube outlet to a desired reaction tube inlet, and the opening of the inlet and outlet of the reaction tube is provided. and the like, but are not limited to these.

In this preferred embodiment (third aspect), each alkylene oxide supply section of the tubular reactor may be supplied with alkylene oxide from one alkylene oxide supply source as shown in FIG. ), the alkylene oxide may be supplied from an alkylene oxide source.

In this preferred embodiment (third aspect), the tubular reactor may be provided with only one thermometer, but it is preferred that the reactor be provided with a plurality of thermometers. With this configuration, it is possible to evenly check the temperature change during the reaction. That is, in a preferred form of the invention, the temperature is measured at at least one point other than the inlet of the tubular reactor. Here, the number of thermometers installed is, for example, 5 or more and 50 or less, preferably 7 or more and 20 or less per 1000 m of tubular reactor length, but is not limited thereto. In addition, the installation interval of the thermometers is immediately after the alkylene oxide supply location to the reactor (for example, 0 m or more and less than 100 m, preferably 0 to 80 m from the alkylene oxide supply location, more preferably the total installation of the thermometers At a rate exceeding 80% of the number of Not limited. By installing the thermometer as described above, the addition reaction of the alkylene oxide to the secondary alcohol alkoxylate can be controlled more reliably. Therefore, the hue of the secondary alcohol alkylene oxide high adduct, which is the final product, can be improved.

In the present preferred embodiment (third aspect), as the reaction conditions (alkoxylation reaction conditions) between the secondary alcohol alkoxylate and the alkylene oxide, the same conditions as known can be adopted. For example, the reaction temperature is 120° C. or higher and 180° C. or lower, preferably 130° C. or higher and 170° C. or lower, but is not limited thereto. Also, the maximum temperature during the reaction is preferably 170°C or less, more preferably less than 165°C. This makes it possible to more effectively suppress the reduction in hue. As for the reaction temperature of the tubular reactor, it is preferable to monitor all the installed thermometers to check whether the peak temperature has exceeded.

Here, the alkylene oxide addition reaction is generally an exothermic reaction. For this reason, the reactor may have a system for circulating a heat medium (eg hot water) as shown in FIG. 4 in order to adjust the reaction temperature. When a system for flowing a heat medium is provided, the heat medium (for example, hot water, steam) after circulation may be taken out and used for other processes. This form leads to reuse of existing energy, reduction of carbon dioxide emissions, etc., and is preferable from the viewpoint of the global environment.

In this preferred embodiment, the reaction time is 0.1 hour or more and 2 hours or less, preferably 0.3 hour or more and 1 hour or less, but is not limited thereto. Under such conditions, a desired amount of alkylene oxide can be added to the secondary alcohol alkoxylate. In addition, the hue of the secondary alcohol alkylene oxide high adduct, which is the final product, can be further improved. The above reaction time is the total reaction time when two or more reactors are used. Alternatively, the number of alkylene oxide additions of the secondary alcohol alkylene oxide high adduct produced by the reaction is measured, and the reaction may be terminated when the desired number of added moles is reached. The reaction pressure may be normal pressure or increased pressure, but from the viewpoint of solubility of alkylene oxide, reaction rate, etc., it is preferable to carry out the reaction under increased pressure using an inert gas such as nitrogen gas.

According to the above preferred embodiment, formula (4): C _m H _2m+1 [O(XO) _q H] (in formula (4), X represents an alkylene group having 1 to 3 carbon atoms; m is 12 to 14; ; q is more than 3.5 and 50 or less). Moreover, since the method according to the preferred embodiment uses a tubular reactor, continuous (mass) production is possible. In addition, the secondary alcohol alkylene oxide high adduct produced by the preferred embodiment has excellent hue and high purity. Therefore, according to the method according to the above-described preferred embodiment, it is possible to continuously (largely) produce secondary alcohol alkylene oxide high adducts with excellent hue.

In formula (4) above, X and m have the same definitions as in formula (1) above. Also, q is the average number of added moles of alkylene oxide in the secondary alcohol alkylene oxide high adduct. q is 5 or more and 50 or less, preferably 6 or more and 15 or less, more preferably 7 or more and 9 or less. Secondary alcohol alkylene oxide high adducts have high water solubility and can be suitably used as surfactants. In this specification, the average number of moles of alkylene oxide added to the secondary alcohol alkoxylate means that the "alkylene oxide adduct" in the above (average number of moles of alkylene oxide added to the alkylene oxide adduct) is replaced with "secondary alcohol A value measured in the same manner is adopted instead of "high alkylene oxide adduct".

The secondary alcohol alkylene oxide high adduct produced by this preferred embodiment is excellent in hue (little or no coloring). Specifically, the hue (APHA) of the secondary alcohol alkylene oxide high adduct, which is the final product, is 70 or less. Here, the hue (APHA) of the secondary alcohol alkylene oxide high adduct is preferably 65 or less, more preferably 60 or less. Here, the lower limit of the hue (APHA) of the secondary alcohol alkylene oxide high adduct is not particularly limited, preferably as low as possible. That is, the secondary alcohol alkylene oxide high adduct has a hue (APHA) of preferably 50-70, more preferably 50-65, and even more preferably 50-60. In the present specification, the hue (APHA) of the secondary alcohol alkylene oxide high adduct adopts the value measured by the method described in the examples below.

The secondary alcohol alkoxylate produced by the method of the present invention or the secondary alcohol alkylene oxide high adduct produced using the secondary alcohol alkoxylate is less likely or not colored. In addition, the secondary alcohol alkoxylate produced by the method of the present invention does not or hardly gels, has excellent detergency, and has little or no odor. Therefore, secondary alcohol alkoxylates and secondary alcohol alkylene oxide high adducts are useful as raw materials for detergent (surfactant) compositions.

Here, the detergent (surfactant) composition containing the secondary alcohol alkoxylate and the secondary alcohol alkylene oxide high adduct may be used alone, but other conventionally known surfactants may be used. They may be used together. Examples of such surfactants include alkylbenzenesulfonates, alkylsulfates, α-olefinsulfonates, alkylsulfonates, aliphatic amidesulfonates, dialkylsulfosuccinates, and alkyl ether sulfates. cationic surfactants such as alkylamine salts and quaternary ammonium salts; and zwitterionic surfactants such as alkylbetaines.

Detergent (surfactant) compositions containing secondary alcohol alkoxylates and secondary alcohol alkylene oxide high adducts can be added with various additives. Such additives include, for example, alkaline agents, builders, fragrances, fluorescent brighteners, coloring agents, foaming agents, foam stabilizers, polishing agents, disinfectants, bleaching agents, enzymes, preservatives, dyes, solvents. etc.

Detergent (surfactant) compositions containing secondary alcohol alkoxylates and secondary alcohol alkylene oxide high adducts can be used for clothing, textiles, tableware, containers, miscellaneous goods, foods, building maintenance products, housing, furniture, It can be effectively used as a cleaning agent for automobiles, aircraft, metal products, etc., as a shampoo, body shampoo, and the like.

Alternatively, secondary alcohol alkoxylates and secondary alcohol alkylene oxide high adducts may be used as emulsifiers. Oily substances that can be used in this case are not particularly limited, and mineral oils, animal and vegetable oils, synthetic oils and the like can be used. These may be used alone or in combination of two or more. Examples of mineral oils include, for example, spindle oil, machine oil, liquid paraffin oil, and the like. Examples of animal and vegetable oils include beef tallow, lard, fish oil, whale oil, rapeseed oil, sesame oil, coconut oil, soybean oil, palm oil, camellia oil, castor oil, and the like. In one aspect of the present invention, the emulsifier can be used for agricultural chemicals, metalworking oils, paints, emulsifiers for emulsion polymerization, and the like.

The effects of the present invention will be described using the following examples and comparative examples. However, the technical scope of the present invention is not to be construed as being limited to the following examples and comparative examples, and examples obtained by appropriately combining the technical means disclosed in each example are also within the scope of the present invention. include. In the following examples, unless otherwise specified, operations were performed at room temperature (25°C). Moreover, unless otherwise specified, "%" and "parts" mean "% by mass" and "parts by mass" respectively.

Example 1
1000 g of a mixture of saturated aliphatic hydrocarbons having 12 to 14 carbon atoms (average molecular weight: 184) and 25 g of metaboric acid are placed in a cylindrical reactor with a capacity of 3 L, and the oxygen concentration is 3.5 vol% and the nitrogen concentration is 96.5 vol%. of gas was blown in at a rate of 430 L per hour, and a liquid-phase oxidation reaction was carried out at 170° C. under normal pressure for 2 hours to obtain an oxidation reaction mixture (oxidation reaction step). The mixture of saturated aliphatic hydrocarbons having 12 to 14 carbon atoms used as a raw material is the total mass of the mixture of saturated aliphatic hydrocarbons having 12 to 14 carbon atoms and saturated aliphatic hydrocarbons having 12 to 14 carbon atoms. It contains at a rate exceeding 95% by mass.

This oxidation reaction mixture was treated at 200 hPa and 170° C. to orthoborate the alcohol contained therein to obtain a borate compound (borate ester mixture) (esterification step). Next, this borate compound (borate ester mixture) was flash-distilled at 170° C. (bottom temperature) and 7 hPa (unreacted saturated aliphatic hydrocarbon recovery step). Next, the residual liquid was hydrolyzed with a large amount (2 mass times the residual liquid) of hot water at 95° C. to separate into an aqueous layer containing orthoboric acid and an organic layer (hydrolysis step). The obtained organic layer was subjected to saponification treatment using sodium hydroxide at 140° C. and washed with water to remove the organic acid and the organic acid ester (saponification step). This organic layer was fractionally distilled at 7 hPa to obtain a fraction with a boiling point range of 95 to 120°C as the first fraction and a fraction with a boiling point range of 120 to 150°C as the second fraction (purification step). Here, the first fraction (95° C. or more and less than 120° C. fraction) was a mixture of small amounts of saturated aliphatic hydrocarbons, carbonyl compounds and monohydric primary alcohols (monoalcohols). The second fraction (boiling point range 120-150° C. fraction) is a mixture of trace amounts of carbonyl compounds and secondary alcohols (monoalcohols), where most of the secondary alcohols are monohydric secondary It is an alcohol and contains more than 95% by weight of secondary alcohols having 12 to 14 carbon atoms relative to the total weight of the mixture. As this second fraction, a mixture of secondary alcohols (average molecular weight: 200) was obtained.

A mixture of secondary alcohols having 12 to 14 carbon atoms (average molecular weight: 200) was charged into a tubular first reactor (tubular reactor, internal volume: 10 L) at 10 kg / hr, and boron trifluoride was added. Ether complex (acid catalyst) was supplied at 24 g/hr. Further, in the first reactor, a total of nine thermometers were installed at positions from the inlet of the reactor to capture the maximum reaction temperature.

Next, ethylene oxide was added to the first reactor at the inlet of the first reactor (first stage), the point 20 m from the inlet (second stage), and the point 40 m from the inlet (third stage). The ethoxylation reaction was carried out at 50° C. for 55 minutes at a rate of 3.3 kg/hr in stages to obtain a reactant. The ethoxylation reaction temperature was in the range of 40 to 70°C. The amount of ethylene oxide supplied in the ethoxylation reaction was about 1.5 mol per 1 mol of the mixture of secondary alcohols.

The above reaction product was supplied to a second reactor (tank reactor, internal volume: 10 L), and an ethoxylation reaction was further performed at 50°C for 55 minutes to obtain a reaction product containing an ethylene oxide adduct.

14.8 L/hr of the reaction product obtained above and 3.7 L/hr of 1% by mass sodium hydroxide aqueous solution were charged into the first mixing vessel of a mixer/settler type apparatus and stirred at 95° C. for 15 minutes. , washed. Thereafter, this mixture is transferred to the first standing tank of a mixer-settler type apparatus, left standing in the first standing tank at 75 ° C. for 30 minutes, and the organic layer containing the ethylene oxide adduct (organic layer 1- 1) and the aqueous layer. 14.8 L/hr of this organic layer (organic layer 1-1) and 3.7 L/hr of water are put into a second mixing tank of a mixer/settler type device, stirred at 95° C. for 15 minutes, and washed. gone. After that, the mixture was transferred to a second stationary tank of a mixer-settler type apparatus, and allowed to stand in the second stationary tank at 70°C for 30 minutes to form an organic layer containing a secondary alcohol ethoxylate precursor ( Separating into an organic layer 1-2) and an aqueous layer, a liquid (1) containing a secondary alcohol ethoxylate precursor having an average ethylene oxide addition mole number (n in formula (1)) of 1.7 was prepared. Obtained. The average ethylene oxide addition mole number (average EO addition mole number) of the secondary alcohol ethoxylate precursor in the liquid (1) was measured according to the following method.

Further, the obtained organic layer (organic layer 1-2) was subjected to an appearance test of the interface between the organic layer and the water layer in a stationary tank and an appearance test of the organic layer according to the following methods. The results are shown in Table 1 below.

<Evaluation method 1>
(1) Measurement of average number of moles of ethylene oxide added (average number of moles of EO) is calculated using Equation 2 below. Incidentally, the hydroxyl value is measured based on the B method of JIS K1557-1:2007. Specifically, a pyridine solution containing phthalic anhydride is used as a sample, and hydroxyl groups are phthalated under pyridine reflux. Excess phthalating reagent is hydrolyzed with water and the phthalic acid produced is titrated with standard sodium hydroxide solution. The hydroxyl value is determined by calculating from the titer difference between the blank test and the sample test.

(2) Appearance test of the interface between the organic layer and the aqueous layer in the stationary tank The presence of an emulsified layer was determined visually for the interface between the organic layer and the aqueous layer in the second stationary tank. In Table 1 below, "◯" indicates that no emulsified layer was observed at the interface between the organic layer and the aqueous layer (less than 5% of the total liquid surface area), and "△" indicates that the emulsified layer was an organic layer. The emulsified layer was slightly observed at the interface between the organic layer and the water layer (5% or more and less than 30% of the total liquid surface area). 30% or more of the area) are shown, respectively. "◯" or "Δ" means that there is no practical problem, and "◯" means that the appearance is very good.

(3) Appearance test of organic layer in stationary tank The presence of crystals in the organic layer in the second stationary tank was determined visually. In Table 1 below, "○" indicates that no crystals were observed in the organic layer, "Δ" indicates that some crystals were observed in the organic layer, and "×" indicates that crystals were observed in the organic layer. Significantly observed, respectively. “◯” or “Δ” means acceptable for practical use, and “◯” means that the appearance is very good.

Next, the liquid (1) containing the secondary alcohol ethoxylate precursor obtained above is supplied to the first distillate cut column (light separation column), and the light components are separated at a bottom temperature of 190° C. and a top pressure of 3 hPa. Evaporate and collect the bottom liquid. This bottom liquid is supplied to an alcohol recovery column (rectification column) and distilled at a bottom temperature of 190 ° C. and a top pressure of 25 hPa to distill off unreacted alcohol and a low EO mole addition fraction to obtain a secondary alcohol. Ethoxylate (1) was obtained. The average ethylene oxide addition mole number (p in formula (2)) of the resulting secondary alcohol ethoxylate (1) was measured and found to be 2.9. The yield of the secondary alcohol ethoxylate 3 mol adduct (EO 3 mol adduct) contained in the secondary alcohol ethoxylate (1) was sufficient ("○" in the item "Yield" in Table 1 below). .

The resulting secondary alcohol ethoxylate (1) was evaluated for hue according to the following method. The results are shown in Table 1 below.

<Evaluation method 2>
(4) Evaluation of Hue Each sample (secondary alcohol ethoxylate) was filled up to the marked line of the colorimetric tube, placed on white paper, and compared with the standard solution in natural light. At this time, the comparison was made by looking into the bottom of the colorimetric tube, and the Hazen unit color number (platinum-cobalt scale) (APHA No.) corresponding to the hue of the sample was selected. In Table 1 below, the smaller the value of the hue (APHA No.), the less the coloring. A hue (APHA No.) of less than 45 is practically desirable.

Example 2
In Example 1, the same operation as in Example 1 was performed except that the amount of ethylene oxide supplied was changed to 2.4 kg/hr, and an organic layer containing a secondary alcohol ethoxylate precursor (organic layer 2-2 ) and an aqueous layer to obtain a liquid (2) containing a secondary alcohol ethoxylate precursor having an average ethylene oxide addition mole number of 1.2. The amount of ethylene oxide supplied in the above ethoxylation reaction was about 1.1 mol per 1 mol of the mixture of secondary alcohols. The average ethylene oxide addition mole number (average EO addition mole number) of the secondary alcohol ethoxylate precursor in the liquid (2) was measured in the same manner as in Example 1.

Further, the obtained organic layer (organic layer 2-2) was subjected to an appearance test of the interface between the organic layer and the water layer in a stationary tank in the same manner as in Example 1, and the appearance of the organic layer. did the test. The results are shown in Table 1 below.

Next, a secondary alcohol ethoxylate (2) was obtained in the same manner as in Example 1, except that the liquid (2) obtained above was used instead of the liquid (1). The average ethylene oxide addition mole number (p in formula (2)) of the resulting secondary alcohol ethoxylate (2) was measured and found to be 2.7. The content (yield) of the secondary alcohol ethoxylate 3 mol adduct (EO 3 mol adduct) contained in the secondary alcohol ethoxylate (2) was sufficient, but slightly lower than in Example 1. (“△” in the item “Yield” in Table 1 below).

The resulting secondary alcohol ethoxylate (2) was evaluated for hue in the same manner as in Example 1. The results are shown in Table 1 below.

Example 3
In Example 1, the same operation as in Example 1 was performed except that the amount of ethylene oxide supplied was changed to 3.0 kg/hr, and an organic layer containing a secondary alcohol ethoxylate precursor (organic layer 3-2 ) and an aqueous layer to obtain a liquid (3) containing a secondary alcohol ethoxylate precursor having an average ethylene oxide addition mole number of 1.6. The amount of ethylene oxide supplied in the above ethoxylation reaction was about 1.4 mol per 1 mol of the mixture of secondary alcohols. The average ethylene oxide addition mole number (average EO addition mole number) of the secondary alcohol ethoxylate precursor in the liquid (2) was measured in the same manner as in Example 1.

Further, the obtained organic layer (organic layer 3-2) was subjected to an appearance test of the interface between the organic layer and the water layer in a stationary tank in the same manner as in Example 1, and the appearance of the organic layer. did the test. The results are shown in Table 1 below.

Next, a secondary alcohol ethoxylate (3) was obtained in the same manner as in Example 1, except that the liquid (3) obtained above was used instead of the liquid (1). The average ethylene oxide addition mole number (p in formula (2)) of the resulting secondary alcohol ethoxylate (3) was measured and found to be 2.9. The content (yield) of the secondary alcohol ethoxylate 3 mol adduct (EO 3 mol adduct) contained in the secondary alcohol ethoxylate (3) was equivalent to that in Example 1 and was sufficient ( “○” in the item of “Yield” in Table 1 below).

The resulting secondary alcohol ethoxylate (3) was evaluated for hue in the same manner as in Example 1. The results are shown in Table 1 below.

Comparative example 1
In Example 1, the same operation as in Example 1 was performed, except that the amount of ethylene oxide supplied was changed to 3.9 kg/hr, and the ethoxylation reaction in the first reactor was performed at 80 ° C. A liquid (4) separated into an organic layer containing a secondary alcohol ethoxylate (comparative organic layer 1-2) and an aqueous layer and containing a secondary alcohol ethoxylate precursor having an average ethylene oxide addition mole number of 2.1 got The amount of ethylene oxide supplied in the ethoxylation reaction was about 1.8 mol per 1 mol of the secondary alcohol. The average ethylene oxide addition mole number (average EO addition mole number) of the secondary alcohol ethoxylate precursor in the liquid (4) was measured in the same manner as in Example 1. It is speculated that the temperature in the first reactor rose to 80°C because a large amount of reaction heat was generated even though ethylene oxide was supplied in such an amount as not to cause a local temperature rise.

The resulting organic layer (comparative organic layer 1-2) was subjected to an appearance test of the interface between the organic layer and the aqueous layer in a stationary tank and an appearance test of the organic layer in the same manner as in Example 1. did The results are shown in Table 1 below.

Next, a comparative secondary alcohol ethoxylate (1) was obtained in the same manner as in Example 1, except that the liquid (4) obtained above was used instead of the liquid (1). . The average number of moles of ethylene oxide added to the resulting comparative secondary alcohol ethoxylate (1) was measured and found to be 3.1. The content (yield) of the secondary alcohol ethoxylate 3 mol adduct (EO 3 mol adduct) contained in the comparative secondary alcohol ethoxylate (1) was considerably lower than that in Example 1 (see below). "X" in the item of Table 1 "Yield").

The resulting comparative secondary alcohol ethoxylate (1) was evaluated for hue in the same manner as in Example 1. The results are shown in Table 1 below.

Comparative example 2
A reactant containing an ethylene oxide adduct was obtained in the same manner as in Example 1.

14.8 L/hr of the reaction product obtained above and 3.7 L/hr of 1% by mass sodium hydroxide aqueous solution were charged into the first mixing vessel of a mixer/settler type apparatus and stirred at 95° C. for 15 minutes. , washed. After that, the mixture was transferred to the first standing tank of a mixer-settler type apparatus, left standing in the first standing tank at 60° C. for 30 minutes, and the organic layer containing the ethylene oxide adduct (comparative organic layer 2 -1) and the aqueous layer. 14.8 L/hr of this organic layer (comparative organic layer 2-1) and 3.7 L/hr of water are put into a second mixing tank of a mixer/settler type device, stirred at 95° C. for 15 minutes, and washed. did After that, this mixture was transferred to a second standing tank of a mixer-settler type apparatus, left standing in the second standing tank at 60° C. for 30 minutes, and an organic layer containing a secondary alcohol ethoxylate precursor ( It was separated into a comparative organic layer 2-2) and an aqueous layer to obtain a liquid (5) containing a secondary alcohol ethoxylate precursor having an average ethylene oxide addition mole number of 1.7. The average ethylene oxide addition mole number (average EO addition mole number) of the secondary alcohol ethoxylate precursor in the liquid (5) was measured in the same manner as in Example 1.

The resulting organic layer (comparative organic layer 2-2) was subjected to an appearance test of the interface between the organic layer and the aqueous layer in a stationary tank and an appearance test of the organic layer in the same manner as in Example 1. did The results are shown in Table 1 below.

Next, a comparative secondary alcohol ethoxylate (2) was obtained in the same manner as in Example 1, except that the liquid (5) obtained above was used instead of the liquid (1). . The average number of moles of ethylene oxide added to the resulting comparative secondary alcohol ethoxylate (2) was measured and found to be 2.9. The content (yield) of the secondary alcohol ethoxylate 3-mol adduct (EO 3-mol adduct) contained in the comparative secondary alcohol ethoxylate (2) was considerably lower than that in Example 1 (see below). "X" in the item of Table 1 "Yield").

The resulting comparative secondary alcohol ethoxylate (2) was evaluated for hue in the same manner as in Example 1. The results are shown in Table 1 below.

From Table 1 above, almost no emulsified layer was observed at the interface in the organic layers 1-2 to 3-2 of Examples 1 to 3, whereas the average ethylene oxide addition moles of the secondary alcohol alkoxylate precursor Formation of an emulsified layer in the comparative organic layer 1-2 of Comparative Example 1 in which the number (n in formula (1)) is 2.1 and in the comparative organic layer 2-2 of Comparative Example 2 in which the standing temperature is 60° C. was well recognized. Further, the secondary alcohol ethoxylates (1) to (3) of Examples 1 to 3 are significantly higher than the comparative secondary alcohol ethoxylates (1) and (2) of Comparative Examples 1 and 2. It can be seen that coloring can be suppressed. In addition to the above, in the organic layers 1-2 to 3-2 of Examples 1 to 3, almost no precipitation of fine crystals was observed, whereas the comparative organic layer 1-2 of Comparative Example 1 and the comparative example A considerable amount of crystals were observed in the comparative organic layer 2-2 of No. 2. Therefore, according to the method of the present invention, the secondary alcohol ethoxylates (1) to (3) of Examples 1 to 3 are converted to the comparative secondary alcohol ethoxylates (1) and (2) of Comparative Examples 1 and 2. ) are considered to have superior quality.

Example 4
A secondary alcohol ethoxylate (3) (average ethylene oxide addition mole number=2.9) was obtained in the same manner as in Example 3.

In a third reactor (U-shaped reactor, outer diameter: 32 mm, inner diameter: 28 mm, tube length: 650 m), the secondary alcohol ethoxylate (3) obtained above (average EO addition moles = 2.9 ) was fed at 1045 kg/hr, 48 mass % aqueous sodium hydroxide solution at 938 g/hr, and ethylene oxide at 830 kg/hr, respectively. The third reactor had a structure in which 33 U-shaped reaction tubes each having a tube length of 10 m were repeatedly connected. Also, in the third reactor, an ethylene oxide feeder (EO feeder) was installed at the position shown in Table 2 below (EO feeder position in Table 2). In addition, in the column of "X _n' <X _{n' +1} " in Table 2 below, three adjacent ethylene oxide supply unit sets satisfying X _n' < X _{n' +1} are marked with "O" and X _n' < X Three adjacent ethylene oxide supply sets that do not satisfy _n'+1 (ie, X _n' >X _n'+1 or X _n' =X _n'+1 ) are indicated by an "x", respectively. As shown in Table 2 below, n is 9, and the number of adjacent three ethylene oxide supply sets satisfying X _n′ <X _n′+1 is 6, so N[X _n′ , X _{n′ +1} ]/(n−1) is about 0.8 (=6/8). In addition, a total of 10 thermometers were installed near each ethylene oxide supply in the third reactor.

Next, ethylene oxide (EO) is supplied to the third reactor through an ethylene oxide supply unit (EO supply unit) installed at the position shown in Table 2 below (EO supply unit position in Table 2). , supplied in the amount shown in Table 2 below (EO supply amount in Table 2), initial nitrogen pressure 1.0 to 2.0 MPa, ethoxylation reaction at 140 to 160 ° C. for 0.5 to 1.0 hours. A further run yielded a reaction containing a secondary alcohol ethoxylate. At this time, the maximum reaction temperature of the tubular reactor measured by 10 thermometers was 160°C. Ethylene oxide (EO) was also fed at the tubesheet side of the third reactor (the ethylene oxide feed was located substantially at the same tubesheet side). Furthermore, the total amount of ethylene oxide supplied in the ethoxylation reaction was about 6 moles per mole of the secondary alcohol ethoxylate precursor. In the column of "Yn _" <Yn _"+1 " in Table 2 below, two adjacent ethylene oxide supply unit sets that satisfy Yn _" <Yn _"+1 are indicated by "O" and Yn _" <Y Two adjacent ethylene oxide supply sets that do not satisfy _n″+1 (ie, Y _n″ >Y _n″+1 or Y _n″ =Y _n″+1 ) are indicated by an “x”, respectively. As shown in Table 2 below, n is 9 and the number of two adjacent ethylene oxide supply sets satisfying Y _n″ <Y _n″+1 is 8, so N[Y _n″ , Y _{n″ +1} ]/n is about 0.9 (=8/9).

The reaction product containing the secondary alcohol ethoxylate obtained above was neutralized with acetic acid until the pH reached 6 to obtain secondary alcohol ethoxylate (A).

Regarding the secondary alcohol ethoxylate (A) obtained above, the average ethylene oxide addition mole number (average EO addition mole number) was measured according to the above method, and was 9. Further, the obtained secondary alcohol ethoxylate (A) was evaluated for hue (APHA) according to the following method, and was 50-55.

Claims (8)

A secondary alcohol is reacted with an alkylene oxide in the presence of a catalyst to obtain a reaction liquid containing an alkylene oxide adduct, the reaction liquid is mixed with water, and then allowed to stand at a temperature exceeding 60° C. to form an aqueous layer and Separating the organic layer, formula (1): C _m H _2m+1 [O(XO) _n H] (in formula (1), X represents an alkylene group having 1 to 3 carbon atoms; m is 11 to 15; n is greater than 0 and less than 2.1), and the liquid is purified to obtain a liquid of the formula (2): C _m H _2m+1 [O (XO) _p H] (in formula (2), X and m have the same definitions as in formula (1) above; p is 2.5 to 3.5). A method for producing a secondary alcohol alkoxylate, comprising obtaining 2. The method according to claim 1, wherein in formula (1), n is greater than 1.5 and less than 1.8. The separation is carried out by mixing the reaction solution with an alkaline aqueous solution to separate into an aqueous layer and an organic layer 1, and then mixing the organic layer 1 with water to separate into an aqueous layer and an organic layer 2. 3. The method according to Item 1 or 2. 4. The method according to claim 3, wherein the mixing volume ratio of the reaction liquid and the alkaline aqueous solution is 1 to 8:1 when the reaction liquid is mixed with the alkaline aqueous solution. The method according to claim 3 or 4, wherein the mixing volume ratio of the organic layer 1 and the water when mixing the organic layer 1 with the water is 1 to 8:1. The method of any one of claims 1-5, wherein the catalyst is an acid catalyst. Using the method according to any one of claims 1 to 6, formula (2): C _m H _2m+1 [O(XO) _p H] (in formula (2), X has 1 to 3 carbon atoms represents an alkylene group; m is 11 to 15; p is 2.5 to 3.5).
Alkylene oxide is added to the secondary alcohol alkoxylate through alkylene oxide supply units installed at the inlet of the tubular reactor and n locations other than the inlet (n is an integer of 2 or more), The secondary alcohol alkoxylate is reacted with the alkylene oxide in the tubular reactor to form formula (4): C _m H _2m+1 [O(XO) _q H] (wherein X is carbon represents an alkylene group with a number of 1 to 3; m is 12 to 14; q is more than 3.5 and 50 or less).
The alkylene oxide supply unit is installed in the tubular reactor so as to satisfy the following formula (i), and further the alkylene oxide is added to the secondary alcohol alkoxylate so as to satisfy the following formula (2). , a method for producing a secondary alcohol alkylene oxide high adduct:

Formula (2): C _m H _{2m +1} [O(XO) pH] (wherein X represents an alkylene group having 1 to 3 carbon atoms; m is 12 ∼ 14; p is 2.5 to 3.5).

Images