KR20120003212A - Method of producing long chain aliphatic tertiary amine using catalyst with liquid phase - Google Patents

Abstract

PURPOSE: A method for manufacturing long chain aliphatic tertiary amine using a liquid catalyst is provided to improve the yield of the amine under a simplified refining condition without a catalyst filtering process. CONSTITUTION: A liquid homogenous mixed metal colloid catalyst for manufacturing long chain aliphatic tertiary amine is represented by chemical formula 1. In the chemical formula 1, the a, the b, and the c are the content of the catalyst with respect to the weight of total metal elements. The M is lanthanum-based elements and is selected from a group including lanthanum(La), cerium(Ce), and samarium(Sm). A method for manufacturing aliphatic tertiary amine reacts C8 to C36 long chain aliphatic alcohol with dimethyl amine under the catalyst.

Description

Method of producing long chain aliphatic tertiary amine using catalyst with liquid phase

The present invention relates to a method for preparing a long chain aliphatic tertiary amine using a liquid phase catalyst.

Aliphatic tertiary amines are intermediates such as domestic or industrial cationic surfactants, amphoteric surfactants, amine oxides, etc., using bovine oil, palm oil, palm oil, rapeseed oil as raw materials.

In particular, dimethyl long-chain alkylamine is made of quaternary amines and is widely used in fabric softeners, antistatic agents, rinse products, cosmetic emulsifiers, dye additives, antibacterial agents, and the like. Various methods of preparing the same aliphatic tertiary amines are known.

Among them, from the viewpoint of the purity and economical efficiency of the synthesized aliphatic tertiary amine, the method of aminating the aliphatic alcohol in the presence of a catalyst is most preferred, and in the presence of an amination catalyst, dimethylamine, methylamine, ammonia or the like is used as an amination agent. When the aliphatic alcohol is reacted, the tertiary amine is synthesized, and in the reaction, by-products such as primary amine and secondary amine may be produced by transalkylation or disproportionation reaction. It is used.

In the process of aminating an aliphatic alcohol to produce a tertiary amine, Cu (copper), Ni (nickel), Co (cobalt), Cr (chromium) catalysts and the like having hydrogenation and dehydrogenation functions are used.

French Patent 780,028 discloses a process for preparing diethyldodecylamine from dodecyl alcohol and diethylamine using a Cu / Ba supported catalyst.

In a similar manner, German Patent No. 2,749,064 discloses a method using a Cu / Re supported catalyst. However, since the catalysts have relatively low activity and selectivity, a large amount of catalysts must be used, and strict reaction conditions such as high reaction pressure and reaction temperature are required, and in order to increase the yield of the product, such as 2.5 to 8.5 wt% Since the use of a large amount of catalysts, there was also an increase in catalyst cost, filtration and recovery of the catalyst.

Accordingly, in order to increase the activity and selectivity of the catalyst, copper-chromite catalysts have been disclosed in US Pat. Nos. 4,138,437 and Japanese Patent Nos. 1977-19604, and nickel (Ni) / copper (Cu) in US Pat. Nos. 3,390,184. / Chromium (Cr) catalysts have been disclosed.

In the case of the chromium-containing catalyst, the amination activity and selectivity were high, but there is a problem that the metal component of the catalyst is dissolved during the reaction, thereby gradually decreasing the activity, and also difficult to separate and purify chromium having carcinogenic toxicity contained in the product. There are disadvantages.

In order to secure these disadvantages, it is a catalyst useful for high activity and repeated use without using chromium which is a toxic component. A mixed metal oxide catalyst consisting of Zn), calcium (Ca) and aluminum (Al) has been disclosed. Using the catalyst, the aliphatic alcohol when the amination reaction was carried out for 3 hours at a temperature of 220 ℃ and atmospheric pressure showed a conversion rate of 100%, the yield of the tertiary amine was 93%, the tertiary amine after distillation The purity of showed 98%.

The catalyst has a high yield and a high purity of the distilled tertiary amine, but the filtration separation time of the catalyst is more than 3 hours, there is a problem that the complexity of the separation step and operating time increases.

US Patent No. 2,953,601, US Patent No. 3,152,185 and US Patent No. 3,223,734 disclose a Raney nickel catalyst having a high specific gravity to improve the filtration and recovery problem of the amination catalyst, US Patent No. 4,152,353 In the arc, a catalyst having 20 to 49 mol% of nickel, 36 to 79 mol% of copper, and 1 to 15 mol% of mixed metals such as iron, zinc, and zirconium was used based on the absence of oxide.

As the specific gravity of the catalyst increased, the recovery and reuse performance of the catalyst was improved, but the production cost of the catalyst was increased, and the yield of the aliphatic tertiary amine was also 70% or less, and the activity was still insufficient.

U.S. Patent Nos. 4,210,605 and 4,254,060 disclose methods using copper (Cu) / nickel (Ni) / barium (Ba) catalysts in the form of liquid homogeneous colloids.

In this method, a three-component metal catalyst consisting of copper stearate, nickel acetyl acetate, barium stearate (0.1% by weight of copper metal, 0.02% by weight of nickel metal, 0.04% by weight of barium metal) was used as a catalyst, and accordingly, The aliphatic alcohol when reacted for 2 hours at a temperature of 210 ° C. and atmospheric pressure showed a conversion of 100%, a yield of tertiary amine was 96%, and a purity of tertiary amine after distillation was 99%.

However, in spite of such excellent reaction characteristics, the catalyst is easily poisoned by trace impurities such as carbon monoxide contained in the reactants and amine by-products in the product, and the activity thereof is reduced, thereby causing problems in repeated use.

Accordingly, the present inventors have tried to prepare a liquid homogeneous mixed metal colloidal catalyst having improved reaction stability while adjusting high constituent colloidal catalyst to maintain high activity and high selectivity. By preparing a three-component colloidal catalyst material composed of the components, and by adjusting the composition ratio of the metal component contained in the catalyst to a specific numerical range, a long-chain aliphatic tertiary amine can be produced in high yield and high purity, and the catalyst is simply separated It was confirmed that the present invention can be reused without deterioration of activity and completed the present invention.

An object of the present invention is to carry out the amination reaction using a liquid homogeneous mixed metal colloid catalyst having excellent reaction stability, reaction selectivity, and activity, so that long-chain aliphatic from long-chain aliphatic alcohol in high yield under simple purification conditions in which the catalyst filtration step is omitted. It is to provide a method for preparing a tertiary amine.

In order to achieve the above object, the present invention provides a liquid homogeneous mixed metal colloid catalyst for preparing aliphatic tertiary amine represented by the following formula (1).

In addition, the present invention is a method for producing an aliphatic tertiary amine comprising the step of reacting a long chain aliphatic alcohol having a carbon number of 8 to 36 with dimethylamine in the presence of a liquid homogeneous mixed metal colloid catalyst represented by the following formula (1) To provide.

[Formula 1]

(In Formula 1, M, a, b and c are as defined herein).

According to the present invention, since the amination reaction is carried out using a liquid homogeneous mixed metal colloid catalyst having excellent reaction stability, reaction selectivity and activity, the catalyst filtration step is omitted, so that purification is simple and high yield of 94% or more. And a long chain aliphatic tertiary amine with high purity of 96% or more, and also, since the catalyst of the present invention does not have a catalyst filtration step, it can be easily separated and reused from the product through a distillation step, and the activity of the catalyst decreases upon reuse. Is not very economical and effective.

Hereinafter, the present invention will be described in detail.

The present invention provides a liquid homogeneous mixed metal colloid catalyst for preparing aliphatic tertiary amine represented by the following Chemical Formula 1.

(In the formula 1,

a, b and c are the content of the total metal element weight of the catalyst,

M is a lanthanum-based metal element)

At this time, M is preferably selected from the group consisting of lanthanum, cerium and samarium.

In the catalyst according to the present invention, the copper content (a) as the catalyst content is 40 to 90% by weight, the nickel content (b) is 4 to 30% by weight, the content of the lanthanum-based metal (M) (c) Silver is preferably 4 to 30% by weight, a is 50 to 80% by weight, b is 8 to 25% by weight, and c is more preferably 4 to 30% by weight.

If the content of copper is more than 90% by weight, the size of the copper crystals increases, the reaction activity is rather reduced. When the content of copper is less than 40% by weight, the copper crystals are small but the amination activity is low and the conversion rate is reduced.

In addition, when the content of nickel is 4% by weight or less, or the content of M is 30% by weight or more, the uniformity and stability of the copper crystals are reduced, so that the conversion rate is low due to low amination reaction activity, and the content of nickel is more than 30% by weight. Or, if the M content is less than 4% by weight, as the acidity and basicity of the catalyst are greatly increased, the aldol condensation and peraminelation side reactions increase, thereby greatly reducing the selectivity of the tertiary amine and increasing the high boiling by-product.

In the catalyst according to the present invention, the catalyst may be obtained by reducing the carboxylic acid salt of the mixed metal of Formula 1 with hydrogen, but is not limited thereto.

In addition, the present invention, in the presence of a liquid homogeneous mixed metal colloid catalyst represented by the following formula (1), a long chain aliphatic alcohol having a carbon number of 8 to 36 by reacting with dimethylamine to prepare a long chain aliphatic tertiary amine Provided are methods for preparing aliphatic tertiary amines.

[Formula 1]

(In the formula 1,

a, b and c are the content of the total metal element weight of the catalyst,

M is a lanthanum-based metal element)

In the production method according to the invention, a is 40 to 90% by weight, b is 4 to 30% by weight, c is 4 to 30% by weight, M is lanthanum (La), cerium (Ce), and samarium At least one metal element selected from (Sm) is shown.

Copper (Cu) is 40 to 90% by weight of the total metal element of the catalyst, nickel (Ni) is 4 to 30% by weight, M is 4 to 30% by weight as the active component of the three-component metal colloid catalyst Preferably, copper is 50 to 80% by weight, nickel (Ni) is 8 to 25% by weight, and M is more preferably 4 to 30% by weight.

If the content of copper is more than 90% by weight, the size of the copper crystals increases, the reaction activity is rather reduced. When the content of copper is less than 40% by weight, the copper crystals are small but the amination activity is low and the conversion rate is reduced.

In addition, when the content of nickel is 4% by weight or less, or the content of M is 30% by weight or more, the uniformity and stability of the copper crystals are reduced, so that the conversion rate is low due to low amination reaction activity, and the content of nickel is more than 30% by weight. Or, if the M content is less than 4% by weight, as the acidity and basicity of the catalyst are greatly increased, the aldol condensation and peraminelation side reactions increase, thereby greatly reducing the selectivity of the tertiary amine and increasing the high boiling by-product.

In the catalyst according to the present invention, the catalyst may be obtained by reducing the carboxylic acid salt of the mixed metal of Formula 1 with hydrogen, but is not limited thereto.

Examples of the long chain aliphatic alcohols include octyl alcohol, lauryl alcohol, myristyl alcohol, stearyl alcohol, bihenyl alcohol, oleyl alcohol, and the like. Oxo alcohol produced | generated at an oxo synthesis process, etc. are mentioned. These may be used alone or in combination of one or more of them.

During the amination reaction, the catalyst is fed to the reactor at 0.01 to 1% by weight as catalyst metal relative to the long chain aliphatic alcohol, and the dimethylamine is fed to the reactor at a flow rate of 1.05 to 1.2 equivalents per hour relative to the long chain aliphatic alcohol. do. In addition, the amination reaction is carried out at a temperature of 210 to 250 ℃ and a pressure of 0.8 to 2.0 atm.

After performing the amination reaction, the product may be distilled to recover the tertiary amine, and the catalyst remaining in the subsequent amination reaction may be reused.

Since the catalyst of the present invention performs the amination reaction using a liquid homogeneous mixed metal colloid catalyst having excellent reaction stability, reaction selectivity, and activity, the catalyst filtration step is omitted, so that purification is simple and high yield of 94% or more. And a long chain aliphatic tertiary amine with high purity of 96% or more, and also, since the catalyst of the present invention does not have a catalyst filtration step, it can be easily separated and reused from the product through a distillation step, and the activity of the catalyst decreases upon reuse. Is not very economical and effective.

Hereinafter, the amination reaction of the aliphatic alcohol using the catalyst of the present invention will be described in detail.

First, a long chain aliphatic alcohol and a carboxylic acid metal catalyst are injected into the reactor. Subsequently, after replacing the reactor with an inert gas such as nitrogen (N ₂ ), the reactor is again replaced with hydrogen (H ₂ ) while heating the reactor to a temperature of 120 ° C.

After filling the hydrogen pressure to 0.5 atm (gauge pressure) and raising the reaction temperature to a temperature of 210 to 250 ° C, dimethylamine gas was supplied to the reactor at a flow rate of 1.05 to 1.2 equivalents per hour with respect to aliphatic alcohol, and 0.8 to The reaction proceeds for 2 to 6 hours at a reaction pressure of 2.0 atmospheres.

Hydrogen, unreacted amine gas, water produced in the reaction, small amounts of unreacted aliphatic alcohol and produced aliphatic amines, etc. are continuously removed from the reactor as exhaust gas and fed to the condenser.

In the condenser the materials are separated into water and organic layer, the double organic layer is recycled to the reactor, and hydrogen and unreacted amine gas are also recycled to the reactor.

After the reaction, the resulting aliphatic tertiary amine is purified by distillation under reduced pressure or the like, and the remaining colloidal catalyst is supplied to the reactor during the next amination reaction.

Hereinafter, the present invention will be described in detail by way of examples.

However, the following examples are merely to illustrate the invention, but the content of the present invention is not limited by the following examples.

< Example  1>

9.0 g (Copper Stearate (I)) of copper (65.2 wt% based on total metal catalysts), 2.4 g of Nickel Stearate (II)) (17.4 wt% of nickel metals based on total metal catalysts) and lanthanum stearate (Lanthanum Stearate (III)) 3.6 g (17.4 wt% of lanthanum metal based on the total metal catalyst) were mixed to prepare a mixture for a liquid homogeneous mixed metal colloidal catalyst.

A 1 L stainless flask reactor was charged with 600 g of long chain aliphatic stearyl alcohol and 15 g of the mixture for the liquid homogeneous mixed metal colloid catalyst (0.23 wt% of metal catalyst to alcohol), followed by stirring and reactor with nitrogen. Was substituted three times.

After repeating the process of supplying nitrogen and depressurizing three times in the same manner as described above, the reactor was heated to a temperature of 120 ° C., hydrogen was again supplied, and the process of depressurizing was repeated twice. Thereafter, hydrogen was charged at 0.5 atmosphere and maintained at a temperature of 200 ° C. for 1 hour, and the temperature was raised to 220 ° C. again, and then 1.1 equivalent ratio of dimethyl amine gas per hour for aliphatic alcohol was flowed into the reactor at 55 L / hr flow rate. The reaction was carried out for 3 hours at a reaction pressure of 1.0 atm.

Hydrogen, unreacted amine gas, water produced in the reaction, a small amount of unreacted aliphatic alcohol and produced aliphatic amine were continuously removed from the reactor as exhaust gas and fed to the condenser, and the condensate of the condenser was separated into water and an organic layer. The organic layer was recycled to the reactor, and hydrogen and unreacted amine gas were also recycled to the reactor. After the reaction, the catalyst and aliphatic tertiary amine were purified from the product by distillation under reduced pressure.

The remaining colloidal catalyst was stirred by adding 600 g of stearyl alcohol, and charged again in the reactor, and used five times for the amination reaction.

The prepared amination reaction product was analyzed by gas chromatography (GC), and the results are shown in Table 1 below. The reaction results were expressed in weight%, and the residual amount of metal contained in the purified aliphatic tertiary amine after distillation was measured by acid decomposition of the sample and quantitatively analyzed by an Inductively Coupled Plasma Atomic Emission Spectrometer. The content of copper, nickel and lanthanum in the purified sample after the first to fifth reactions of the reaction was 1 ppm or less.

< Example  2>

10.4 g of copper stearate, 1.0 g of nickel stearate, and 3.6 g of lanthanum stearate were used to prepare the catalyst, except that the metal composition in the catalyst was used at a composition ratio of 75.2 wt% copper, 7.4 wt% nickel, and 17.4 wt% lanthanum. It was carried out in the same manner as in Example 1 to prepare a long chain aliphatic tertiary amine, the reaction results are shown in Table 1 below.

< Example  3>

Example 1 except that 10.4 g of copper stearate, 2.4 g of nickel stearate and 1.5 g of lanthanum stearate were used to prepare the catalyst, except that the metal composition in the catalyst was 75.2 wt% copper, 17.4 wt% nickel, and 7.4 wt% lanthanum. The long chain aliphatic tertiary amine was prepared by the same method as described in Table 1 below.

< Example  4>

3.6 g of cerium stearate instead of lanthanum stearate was used to prepare the catalyst in the same manner as in Example 1, except that the metal composition of the catalyst was 65.2 wt% copper, 17.4 wt% nickel, and 17.4 wt% cerium. To prepare a long chain aliphatic tertiary amine, the results are shown in Table 1 below.

< Example  5>

3.9 g of samarium stearate instead of lanthanum stearate was used to prepare the catalyst in the same manner as in Example 1, except that the metal composition of the catalyst was 65.2 wt% copper, 17.4 wt% nickel, and 17.4 wt% samarium. To prepare a long chain aliphatic tertiary amine, the results are shown in Table 1 below.

< Comparative example  1>

12.4 g of copper stearate, 1.0 g of nickel stearate and 0.9 g of lanthanum stearate were used to prepare the catalyst, except that the metal composition in the catalyst was 90.2 wt% copper, 7.4 wt% nickel, and 2.4 wt% lanthanum. Performed in the same manner as in Example 1 to prepare a long chain aliphatic tertiary amine, the results are shown in Table 1 below.

< Comparative example  2>

The catalyst was prepared using 8.3 g of copper stearate, 4.5 g of nickel stearate, and 1.5 g of lanthanum stearate, except that the metal composition in the catalyst was 60.2 wt% copper, 32.4 wt% nickel, and 7.4 wt% lanthanum. Performed in the same manner as in Example 1 to prepare a long chain aliphatic tertiary amine, the results are shown in Table 1 below.

< Comparative example  3>

3.5 g of barium stearate instead of lanthanum stearate was used to prepare the catalyst in the same manner as in Example 1, except that the metal composition in the catalyst was 65.2 wt% copper, 17.4 wt% nickel, and 17.4 wt% barium. To prepare a long chain aliphatic tertiary amine, the results are shown in Table 1 below.

Catalyst composition
(Component weight%)
Reaction count Aliphatic tertiary amine assay result reaction
yield(%) distillation
yield(%) water(%) Example 1 Cu (65.2), Ni (17.4), La (17.4) One 97.2 95.2 98.0 3 96.2 95.0 98.0 5 96.0 94.8 97.9 Example 2 Cu (75.2), Ni (7.4), La (17.4) One 96.0 93.7 97.0 5 95.8 93.5 97.3 Example 3 Cu (75.2), Ni (17.4), La (7.4) One 98.0 94.0 98.2 5 95.2 93.0 98.7 Example 4 Cu (65.2), Ni (17.4), Ce (17.4) One 95.2 95.0 97.7 5 94.2 94.0 97.3 Example 5 Cu (65.2), Ni (17.4), Sm (17.4) One 95.7 95.1 97.0 5 94.2 95.0 96.6 Comparative Example 1 Cu (90.2), Ni (7.4), La (2.4)
One 78.0 73.6 97.5 5 76.5 72.6 96.3 Comparative Example 2 Cu (60.2), Ni (32.4), La (7.4) One 87.5 72.6 95.6 5 81.5 70.3 92.3 Comparative Example 3 Cu (65.2), Ni (17.4), Ba (17.4) One 97.6 92.2 96.8 3 86.6 76.6 88.6

In Table 1, when the catalyst is used once, the aliphatic tertiary amines prepared in Examples 1 to 5 of the present invention have the same reaction yield, distillation yield, and purity as those of the Cu · Ni · Ba catalyst of Comparative Example 3. Indicated. However, when the catalyst is reused three or five times, the catalyst of the present invention has excellent reaction yield, distillation yield, and purity with a reaction yield of 95.2 to 97.2%, a distillation yield of 95.0 to 95.2%, and a purity of 97.0 to 98.0%. However, the Cu, Ni, Ba catalyst of Comparative Example 3, the reaction yield was 86.6%, the distillation yield was 76.6% and the purity was 86.6%, it was confirmed that the catalyst activity is significantly reduced depending on the number of reactions.

In addition, looking at the reactivity according to the composition ratio of the catalyst, in the composition ratio of the present invention shows a good reaction yield of 90% or more even in one time and a plurality of repeated reuse, while the composition ratio of copper is 90.2% (Comparative Example 1) When the composition ratio of 76.5 to 78% and nickel was 32.4% (Comparative Example 2), it was confirmed that the reaction yield was low, such as showing a reaction yield of 81.5 to 87.5%.

< Example  6>

In the amination reaction, a long chain aliphatic tertiary amine was prepared in the same manner as in Example 1 except that 600 g of bihenyl alcohol was used instead of stearyl alcohol. The bihenyl alcohol was reacted at a temperature of 230 ℃, the results are shown in Table 2 below.

< Example  7>

In the amination reaction, a long chain aliphatic tertiary amine was prepared in the same manner as in Example 1 except that 600 g of oleyl alcohol was used instead of stearyl alcohol. The oleyl alcohol was reacted at a temperature of 215 ℃, the results are shown in Table 2 below.

Reactant Reaction count
Aliphatic tertiary amine assay Reaction yield (%) Distillation yield (%) water(%) Example 1 Stearyl alcohol One 97.2 95.2 98.0 5 96.0 94.8 97.9 Example 6 Bihenyl alcohol One 97.2 93.8 98.0 5 97.0 93.6 97.8 Example 7 Oleyl alcohol One 97.3 93.7 98.3 5 97.0 93.5 98.1

As shown in Table 2, in preparing the aliphatic tertiary amine, the catalyst of the present invention was confirmed to maintain a high reaction yield, distillation yield and purity regardless of the type of alcohol.

Therefore, the liquid catalyst according to the present invention exhibits a high reaction yield of at least 94% and a high purity of at least 96% regardless of the number of times of repeated reuse and aliphatic tertiary amine preparation, and a high purity of at least 96%. Since it is economical, it can be usefully used for preparing aliphatic tertiary amines.

Claims (15)

Liquid homogeneous mixed metal colloid catalyst for preparing aliphatic tertiary amine represented by Formula 1 below:
[Formula 1]

(In Formula 1,
a, b and c are the content of the total metal element weight of the catalyst,
M is a lanthanum-based metal element).
The liquid homogeneous mixed metal colloid catalyst of claim 1, wherein M is selected from the group consisting of lanthanum (La), cerium (Ce), and samarium (Sm).
The liquid homogeneous mixed metal colloid catalyst of claim 1, wherein a is 40 to 90% by weight, b is 4 to 30% by weight, and c is 4 to 30% by weight.
The liquid homogeneous mixed metal colloid catalyst for preparing aliphatic tertiary amines according to claim 3, wherein a is 50 to 80% by weight, b is 8 to 25% by weight, and c is 4 to 30% by weight.
The liquid homogeneous mixed metal colloid catalyst for preparing aliphatic tertiary amines according to claim 1, wherein the catalyst is obtained by reducing a carboxylic acid salt of a mixed metal of Formula 1 with hydrogen.
6. The liquid homogeneous mixed metal colloid catalyst for preparing aliphatic tertiary amines according to claim 5, wherein the carboxylic acid is stearic acid.
In the presence of a liquid homogeneous mixed metal colloid catalyst represented by the formula (1), a method for producing an aliphatic tertiary amine comprising the step of reacting a long chain aliphatic alcohol having a carbon number of 8 to 36 with dimethylamine.
[Formula 1]

(In Formula 1,
a, b and c are the content of the total metal element weight of the catalyst,
M is a lanthanum-based metal element).
The method of claim 7, wherein M is selected from the group consisting of lanthanum (La), cerium (Ce) and samarium (Sm).
The method of claim 7, wherein a is 40 to 90% by weight, b is 4 to 30% by weight, and c is 4 to 30% by weight.
10. The method of claim 9, wherein a is 50 to 80% by weight, b is 8 to 25% by weight, and c is 4 to 30% by weight.
The method of claim 7, wherein the long-chain aliphatic alcohol is octyl alcohol, lauryl alcohol, myristyl alcohol, stearyl alcohol, bihenyl alcohol, oleyl alcohol, Ziegler alcohol produced in the Ziegler process and oxo alcohol produced in the oxo synthesis process Method for producing an aliphatic tertiary amine, characterized in that at least one selected from the group consisting of.
8. The method of claim 7, wherein the catalyst is used in an amount of 0.01 to 1% by weight based on the long chain aliphatic alcohol.
8. The method for preparing aliphatic tertiary amines according to claim 7, wherein the dimethylamine is supplied at a flow rate of 1.05 to 1.2 equivalents per hour with respect to the long chain aliphatic alcohol.
The method of claim 7, wherein the reaction is performed at a temperature of 210 to 250 ° C. and a pressure of 0.8 to 2.0 atmospheres.
8. The method of claim 7, wherein after the completion of the reaction, the catalyst is simply separated from the product through a distillation step without a catalyst filtration step and reused.