阅读说明：本技术 将酸氢化成醇的制备方法 (Process for the hydrogenation of acids to alcohols ) 是由 周俊彦 张鸿铭 邱圣涵 林裕川 江家维 杜政杰 于 2018-07-26 设计创作，主要内容包括：本发明提供一种将酸氢化成醇的制备方法,其步骤包括：将含铜层状硅酸盐(copper phyllosilicate)作为催化剂,经还原处理后,在该经还原的催化剂的存在下将酸氢化成醇,其中,该催化剂包含载体SiO<Sub>2</Sub>以及活性金属Cu。本发明将酸氢化成醇的制备方法不仅可将羧酸氢化成醇,还可将二元酸直接氢化成二元醇、环烷羧酸直接氢化成环烷醇,具有简化反应步骤、降低生产成本、降低反应压力、提高反应收率等优势。(The invention provides a preparation method for hydrogenating acid into alcohol, which comprises the following steps: copper-containing sheet silicate (copper phyllosilicate) is used as a catalyst, and after reduction treatment, acid is hydrogenated into alcohol in the presence of the reduced catalyst, wherein the catalyst comprises SiO carrier 2 And the active metal Cu. The preparation method for hydrogenating acid into alcohol not only can hydrogenate carboxylic acid into alcohol, but also can directly hydrogenate dibasic acid into dihydric alcohol and naphthenic carboxylic acid into cycloalkanol, and has the advantages of simplifying reaction steps, reducing production cost, reducing reaction pressure, improving reaction yield and the like.)

1. A process for the preparation of an alcohol by hydrogenation of an acid, comprising the steps of:

using a copper-containing sheet silicate as a catalyst, reducing the catalyst, and hydrogenating the acid to alcohol in the presence of the reduced catalyst, wherein the catalyst comprises SiO as a carrier₂And the active metal Cu.

2. The process for the preparation of an alcohol by hydrogenation of an acid as claimed in claim 1, wherein the catalyst has I by IR spectroscopy₆₇₀/I₈₀₀The peak area ratio ranges from 0.05 to 0.5.

3. The process for the preparation of an alcohol by hydrogenation of an acid as claimed in claim 2, wherein the catalyst has I by IR spectroscopy₆₇₀/I₈₀₀The peak area ratio ranges from 0.1 to 0.37.

4. The method of claim 2, wherein the acid comprises one or a combination of a monobasic acid, a hydroxyl group-containing monobasic acid, a dibasic acid, and a polybasic acid.

5. The method of claim 4, wherein the acid comprises one or more compounds having a carboxyl group and the alcohol is a monohydric alcohol or a dihydric alcohol.

6. The method of claim 5, wherein the acid comprises one selected from the group consisting of formic acid, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, caprylic acid, succinic acid, glutaric acid, adipic acid, sebacic acid, and 1, 4-cyclohexanedicarboxylic acid; the corresponding alcohols produced are methanol, ethanol, propanol, butanol, pentanol, hexanol, octanol, butanediol, pentanediol, hexanediol, decanediol and 1, 4-cyclohexanedimethanol, respectively.

7. The method according to claim 4, wherein the reduction treatment comprises pretreating the copper-containing layered silicate at 120 to 400 ℃ for 1 to 7 hours in a hydrogen atmosphere.

8. The process for producing an alcohol by hydrogenation of an acid according to claim 4, wherein the pressure at the time of the reaction is 50kg/cm²To 100kg/cm²。

9. The process for producing an alcohol by hydrogenation of an acid according to claim 8, wherein the pressure during the reaction is 90kg/cm²。

10. A method for preparing dihydric alcohol by directly hydrogenating dibasic acid, which is characterized by comprising the following steps:

the process for the production of alcohols by hydrogenation of acids as claimed in any of claims 1 to 9, characterized in that the dibasic acids are directly hydrogenated to glycols in the presence of the reduced catalyst.

11. A method for preparing naphthenic carboxylic acid directly hydrogenated into naphthenic alcohol is characterized by comprising the following steps:

the production process for hydrogenating an acid into an alcohol according to any one of claims 1 to 9, wherein naphthenic carboxylic acid is directly hydrogenated into a cycloalkanol in the presence of the reduced catalyst.

Technical Field

The present invention relates to a method for preparing alcohol by hydrogenating acid, especially a method for directly hydrogenating carboxylic monoacid, diacid or naphthenoid with carboxyl (-COOH) into alcohol.

Background

However, the utilization of fossil fuels causes a great deal of environmental pollution, and fossil fuels are non-renewable, and resources are increasingly scarce, so that the search for other methods for producing monohydric alcohols and dihydric alcohols is the focus of research in related industries at present.

Although it is known that monohydric and dihydric alcohols can be obtained by hydrogenation of organic acids, the conditions for hydrogenation of carboxylic acids are very severe because of the low electrophilicity of the C ═ O bonds in organic acids, for example: higher reaction temperature and higher hydrogen pressure, etc. The more common way to hydrogenate acids to alcohols is a two-step process of esterifying organic acids and then further hydrogenating the esters to alcohols.

In order to increase the yield of the hydrogenation reaction, acid hydrogenation is often carried out using a noble metal catalyst having high activity together with one or more metals, and it has been reported that a copper-based catalyst is used in the reaction, but only a hydroxyl group-containing monobasic acid is hydrogenated to an alcohol.

Disclosure of Invention

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description, serve to explain the principles of the invention.

FIG. 1 is an infrared spectrum of a catalyst used in a preferred embodiment of the present invention.

Detailed Description

The following detailed description, embodiments and technical contents of the present invention are described with reference to the drawings, however, it should be understood that these embodiments are only for the purpose of facilitating the understanding of the present invention and are not intended to limit the scope of the present invention.

The word "comprise" or "comprising" when used herein is intended to mean that it does not exclude the presence or addition of one or more other elements, steps, operations and/or elements. "A" means that the grammatical object of the object is one or more than one (i.e., at least one).

The invention provides a preparation method for hydrogenating acid into alcohol, which comprises the following steps: using a copper-containing sheet silicate (copper phyllosilicate) as a catalyst, reducing the catalyst, and hydrogenating the acid to alcohol in the presence of the reduced catalyst, wherein the catalyst comprises a carrier SiO₂And the active metal Cu.

The invention also provides a preparation method for directly hydrogenating dibasic acid into dihydric alcohol, which comprises the following steps: copper-containing layered silicate (copper phyllosilicate) is used as a catalyst, and after reduction, the copper-containing layered silicate is subjected to reduction in the presence of the reduced catalystThe dibasic acid is directly hydrogenated into the dihydric alcohol, wherein the catalyst comprises a carrier SiO₂And the active metal Cu.

The invention also provides a preparation method for directly hydrogenating naphthenic carboxylic acid into naphthenic alcohol, which comprises the following steps: copper-containing layered silicate (copper phyllosilicate) is used as a catalyst, and after reduction, naphthenic carboxylic acid is directly hydrogenated into alkanol in the presence of the reduced catalyst, wherein the catalyst comprises SiO carrier₂And the active metal Cu.

The term "method for preparing an alcohol by hydrogenating an acid" as used herein refers to a method for preparing an alcohol by hydrogenating an acid in one step, i.e., directly preparing an alcohol by hydrogenating an acid, rather than a two-step method comprising esterifying an acid to form an ester and then hydrogenating the ester to form an alcohol.

The "acid" as used herein refers to a reactant of the preparation method of the present invention. In a preferred embodiment, the acid is, for example but not limited to: comprises one or a combination of a monobasic acid, a hydroxyl group-containing monobasic acid, a dibasic acid and a polybasic acid. In a preferred embodiment, the acid comprises one or more compounds having a carboxyl group (-COOH), i.e., the acid comprises one or more compounds having a carboxyl group. . In a preferred embodiment, the acid is, for example but not limited to: comprises one or a combination of formic acid, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, caprylic acid, succinic acid, glutaric acid, adipic acid, sebacic acid, 1, 4-cyclohexanedicarboxylic acid and other organic acids.

The term "alcohol" as used herein refers to the product of the preparation process of the present invention, which may be a monohydric alcohol, a dihydric alcohol or a polyhydric alcohol, depending on the reactants. In a preferred embodiment, in the method of the present invention for the hydrogenation of an acid to an alcohol, the reactant is a monocarboxylic acid and the product is a monohydric alcohol. In a preferred embodiment, in the method for preparing alcohol by hydrogenating acid of the present invention, the reactant is dicarboxylic acid and the product is diol. In a preferred embodiment, in the process for the hydrogenation of an acid to an alcohol of the present invention, the reactant is a naphthenic carboxylic acid and the product is a cycloalkanol. In a preferred embodiment, in the method of the present invention for preparing alcohols by hydrogenating acids, when the reactant acid is one of formic acid, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, caprylic acid, succinic acid, glutaric acid, adipic acid, sebacic acid, 1, 4-cyclohexanedicarboxylic acid, the corresponding alcohol is methanol, ethanol, propanol, butanol, pentanol, hexanol, octanol, butanediol, pentanediol, hexanediol, decanediol, 1, 4-cyclohexanedimethanol, respectively.

The "catalyst" referred to herein is the use of copper-containing layered silicate (CPS), which is a good catalyst in hydrogenation. The copper-containing layered silicate forms a layered structure with highly dispersed active metal copper (Cu), while Cu⁰And Cu⁺The copper-containing phyllosilicate used in the invention has excellent catalytic performance due to the synergistic effect of the copper-containing phyllosilicate and the copper-containing phyllosilicate. And the copper and the silicon dioxide have stronger interaction, so that the catalyst has good heat resistance, and the catalyst can be prevented from being deactivated due to the agglomeration of active metals. In a preferred embodiment, the copper-containing layered silicate of the present invention has an infrared spectroscopy (IR) analysis of 670 and 800cm^-1Band of (1) found experimentally₆₇₀And I₈₀₀The area ratio of (A) can be taken as the proportion occupied by the layered structure when I₆₇₀And I₈₀₀When the area ratio is too low, the layered structure of the copper-containing layered silicate is less, and the surface area of copper metal is too small, so that the reaction rate is too slow, and even catalytic reaction cannot be carried out; when I is₆₇₀And I₈₀₀When the area ratio is too high, it means that the layered structure of the copper-containing layered silicate is large, and the surface area of copper metal is too large, so that the activity of the catalyst becomes too high, and the reactant is excessively hydrogenated, resulting in an increase in by-products, thereby affecting the yield, and therefore it is preferable to have I₆₇₀/I₈₀₀The peak area ratio (ratio) ranges from 0.05 to 0.5, such as but not limited to: 0.05, 0.07, 0.1, 0.13, 0.15, 0.17, 0.2, 0.23, 0.25, 0.27, 0.3, 0.33, 0.35, 0.37, 0.4, 0.43, 0.45, 0.47, or 0.5. In a more preferred embodiment, the copper-containing layered silicate of the invention has an IR spectrum analysis of I₆₇₀/I₈₀₀Peak area ratioIn the range of 0.1 to 0.37, such as but not limited to: 0.1, 0.11, 0.12, 0.13, 0.14, 0.15, 0.16, 0.17, 0.18, 0.19, 0.2, 0.21, 0.22, 0.23, 0.24, 0.25, 0.26, 0.27, 0.28, 0.29, 0.3, 0.31, 0.32, 0.33, 0.34, 0.35, 0.36, 0.37.

According to the present invention, it is found that there is a correlation between the yield of the product "alcohol" and the surface area of the active metal, and therefore, the copper particles dispersed in the layered silicate are preferably copper nanoparticles.

The preparation method of the invention uses the copper-containing layered silicate as the catalyst, and the catalyst is subjected to reduction treatment after preparation and before use, and the reduction treatment comprises the following steps: the copper-containing layered silicate is reduced by exposing it to hydrogen, however, the method of reducing the catalyst is not limited in the present invention. In a preferred embodiment, the reduction treatment is carried out by pretreating the copper-containing layered silicate at 120 to 400 ℃ for 1 to 7 hours in a hydrogen atmosphere; the temperature of the reduction reaction is not limited to: 120 deg.C, 150 deg.C, 170 deg.C, 200 deg.C, 220 deg.C, 250 deg.C, 270 deg.C, 300 deg.C, 320 deg.C, 350 deg.C, 370 deg.C, or 400 deg.C; the time of the aforementioned reduction reaction is, for example, but not limited to: 1 hour, 2 hours, 3 hours, 4 hours, 5 hours, 6 hours, 7 hours, or the like.

In the preparation method of the present invention, a certain reaction pressure is required to be maintained during the hydrogenation reaction, and in a preferred embodiment, the reaction pressure may be 50 to 200kg/cm²Examples, but not limited to: 50kg/cm²、60kg/cm²、70kg/cm²、80kg/cm²、90kg/cm²、100kg/cm²、110kg/cm²、120kg/cm²、130kg/cm²、140kg/cm²、150kg/cm²、160kg/cm²、170kg/cm²、180kg/cm²、190kg/cm²Or 200kg/cm²And the like. In a more preferred embodiment, the reaction pressure of the preparation process of the present invention is 90kg/cm²。

In the preparation method of the present invention, the hydrogenation reaction has a better reaction temperature and reaction time, and in a preferred embodiment, the hydrogenation reaction is performed at a temperature of 150 ℃ to 350 ℃ for 3 to 24 hours, and the reaction temperature is, for example, but not limited to: 150 ℃, 160 ℃, 170 ℃, 180 ℃, 190 ℃, 200 ℃, 210 ℃, 220 ℃, 230 ℃, 240 ℃, 250 ℃, 260 ℃, 270 ℃, 280 ℃, 290 ℃, 300 ℃, 310 ℃, 320 ℃, 330 ℃, 340 ℃, or 350 ℃, and the like, and the reaction time is, for example, but not limited to: 3 hours, 3.5 hours, 4 hours, 4.5 hours, 5 hours, 5.5 hours, 6 hours, 6.5 hours, 7 hours, 7.5 hours, 8 hours, 8.5 hours, 9 hours, 9.5 hours, 10 hours, 10.5 hours, 11 hours, 11.5 hours, 12 hours, 12.5 hours, 13 hours, 13.5 hours, 14 hours, 14.5 hours, 15 hours, 15.5 hours, 16 hours, 16.5 hours, 17 hours, 17.5 hours, 18 hours, 18.5 hours, 19 hours, 19.5 hours, 20 hours, 20.5 hours, 21 hours, 21.5 hours, 22 hours, 22.5 hours, 23 hours, 23.5 hours, or 24 hours, etc.

With respect to the reaction pressure, temperature and time of the hydrogenation reaction, the reaction conditions may be adjusted according to the reactants and catalyst and the desired effect, and in a preferred embodiment, the hydrogenation reaction is carried out in the presence of the reduced copper-containing layered silicate with a gas pressure of 90kg/cm at 240 ℃²And reacting for 12 to 20 hours. The advantage of such hydrogenation conditions is that the reaction pressure only has to be maintained at 90kg/cm²The method can achieve the excellent effect of hydrogenating the carboxylic acid into the alcohol in one step with the yield of more than 95 percent, and overcome the defects that the reaction condition is difficult because the high-pressure reaction needs to be maintained in the conventional preparation method or the production cost is high because of a noble metal catalyst.

The following examples are intended to illustrate, but not to limit, the present invention.

PREPARATION EXAMPLE 1 preparation of copper-containing layered silicate catalyst

(1) 15g of copper nitrate and 46ml of aqueous ammonia were taken and added to 300ml of pure water.

(2) The above solution was added to 45ml of silica sol and stirred for 1 day.

(3) The solution was heated in a water bath at 80 ℃ until the pH decreased from 11 to 7.

(4) The above solution was placed in an oven at 150 ℃ and heated for 1 day, filtered and dried at 60 ℃.

(5) Finally, the copper-containing layered silicate Catalyst (CPS) is obtained by placing the copper-containing layered silicate catalyst into a high-temperature furnace and calcining the copper-containing layered silicate catalyst at 400 ℃ for 4 hours.

[ example 1]

(1) 0.3g of the copper-containing layered silicate catalyst of preparation example 1 was placed in a 1 liter autoclave and subjected to reduction treatment in a hydrogen atmosphere at 350 ℃ for 3 hours.

(2) Next, 0.6g of adipic acid as a reactant, and 180ml of 1, 4-dioxane as a solvent were charged into the autoclave.

(3) Introducing nitrogen for 3 times, introducing hydrogen for 3 times, and introducing hydrogen to increase pressure to 54kg/cm²。

(4) The temperature was raised to 240 ℃ and the pressure was maintained at 90kg/cm²The reaction was stirred for 12 hours.

(5) After completion of the reaction, the catalyst was filtered and analyzed by a gas chromatograph, and the results are shown in Table 1.

[ examples 2 to 12]

The reaction was carried out in the same manner as in example 1 except that the reactants were changed to those shown in Table 1, and the results are shown in Table 1.

TABLE 1

The results show that, as shown in example 1 of table 1, adipic acid was successfully converted into hexanediol by the preparation method of the present invention, and the product yield was as high as 95.9%, confirming that the preparation method of the present invention can be applied to the direct hydrogenation of carboxylic acids to alcohols, and that the preparation method of the present invention can be applied to the direct hydrogenation of dibasic acids to glycols, and the product yield was as high as 95% or more.

As shown in example 2 of table 1, the preparation method of the present invention successfully converts 1, 4-cyclohexanedicarboxylic acid into 1, 4-cyclohexanedimethanol with a product yield as high as 97.2%, confirming that the preparation method of the present invention can be applied to the direct hydrogenation of naphthenic carboxylic acid into cycloalkanol, and that the preparation method of the present invention can be applied to the direct hydrogenation of naphthenic dibasic acid into naphthenic diol with a product yield of more than 95%.

As shown in examples 3 to 9 of Table 1, the method of the present invention successfully converts monobasic acids such as formic acid, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid and caprylic acid into monohydric alcohols such as methanol, ethanol, propanol, butanol, pentanol, hexanol and octanol, respectively, and the yield of the corresponding monobasic alcohols is as high as 95.7% to 98.6%, and it is evident that the method of the present invention can directly hydrogenate monobasic acids into monohydric alcohols, and the yield of the corresponding monobasic alcohols is 95% or more.

As shown in examples 10 to 12 in table 1, the preparation method of the present invention can successfully convert dibasic acids such as succinic acid, glutaric acid, and sebacic acid into diols such as butanediol, pentanediol, and decanediol, and their corresponding diols, respectively, in addition to converting adipic acid into hexanediol, and the product yield reaches 95.1% to 97.2%, so that the preparation method of the present invention for hydrogenating acids into alcohols can directly hydrogenate dibasic acids into diols, and the product yield reaches 95% or more.

Thus, as demonstrated in examples 1 to 12, the preparation process of the present invention can hydrogenate an acid to the corresponding alcohol in one step, and the reaction pressure is maintained at only 90kg/cm²The yield of the product is as high as 95.1 percent to 98.6 percent.

[ preparation example 2]Copper silicon shell (Cu/SiO)₂) Preparation of the catalyst

(1) 15g of copper nitrate was taken and added to 13ml of pure water.

(2) An aqueous solution of copper nitrate was uniformly sprayed on 16g of silica.

(3) It was placed in an oven at 60 ℃ and dried overnight.

(4) Finally, the catalyst is put into a high-temperature furnace at 400 ℃ to be calcined for 4 hours to obtain the shell-shaped copper-silicon catalyst.

Comparative example 1

The reaction was carried out in the same manner as in example 1 except that the catalyst was changed to that of preparation example 2, whereby the yield of hexanediol was 69.3%.

Comparative example 2

Except that the catalyst was changed to commercially available non-lamellar Cu/SiO₂The reaction was carried out in the same manner as in example 1 except for using a catalyst (CU60/8T, Johnson Matthey corporation), whereby the yield of hexanediol was 72.8%.

Comparative example 3

Except that the catalyst is changed into a commercial noble metal Ru/Al₂O₃A reaction was carried out in the same manner as in example 1 except for using a catalyst (T-8403, manufactured by Clariant corporation), whereby the yield of hexanediol was 52.6%.

Comparative example 4

The reaction was carried out in the same manner as in example 1 except that the catalyst was changed to a commercially available Cu/Al/Mn multimetal Cu/Al catalyst (T-8706, manufactured by Clariant Co., Ltd.), whereby the yield of hexanediol was 76.6%.

Thus, the catalyst component used has Cu/SiO₂However, the yields of the products of comparative examples 1 and 2, which do not have a layered structure, were 69.3% and 72.8%, respectively, which is much lower than the yield of 95.9% of the product of example 1 under the same reaction conditions. If the catalysts containing copper component are compared (i.e., comparative examples 1, 2, 4), the yield of the product is about 69% -77%, which is much lower than the yield of 95.9% of the product obtained in example 1 under the same reaction conditions. Furthermore, generally speaking, higher product yields would be expected using noble metal catalysts, but comparative example 3 uses a commercially available noble metal catalyst Ru/Al₂O₃The product yield of (a) is only 52.6%, which is much lower than the product yield of 95.9% of example 1 under the same reaction conditions. It is apparent that the yields of hydrogenation of adipic acid to hexanediol in comparative examples 1 to 4 are only 52.6% to 76.6%, which is much lower than the yield of the product of example 1 in which adipic acid is also converted, i.e. the preparation process of the present invention using a copper-containing layered silicate as a reaction catalyst, not only allows the acid to be hydrogenated to the corresponding alcohol in only one step, but also results in superior efficacy which cannot be achieved with other alternative catalysts.

[ preparation example 3]

A copper-containing layered silicate catalyst was obtained in the same manner as in preparation example 1, except that 7g of copper nitrate and 21ml of aqueous ammonia were used.

[ preparation example 4]

A copper-containing layered silicate catalyst was obtained in the same manner as in preparation example 1, except that 27g of copper nitrate and 82ml of aqueous ammonia were used.

IR spectrum measurement and analysis

For preparation examples 1 to 4, IR spectrum measurement and analysis were performed.

IR measurement: preparing 2 wt% catalyst in potassium bromide (KBr) by using a spectrum 1000 type (from Perkin Elmer company), pressing the sample into a test piece, putting the test piece into a machine for analysis, and analyzing the test piece at a wavelength of 400-4400 cm^-1The obtained infrared spectrum is shown in FIG. 1.

Spectral analysis: calculation of I₆₇₀And I₈₀₀Peak area of (D) to obtain I₆₇₀And I₈₀₀The results of the area ratios of (a) to (b) are shown in Table 2.

[ examples 13 and 14]