Preparation method of cetyl ethyl hexanoate

Abstract

The invention discloses a preparation method of cetyl alcohol ethyl hexanoate, and the preparation method comprises the following steps: under the protection of a catalyst and nitrogen, ethyl hexanoic acid and cetyl alcohol are subjected to an esterification reaction, the catalyst is a titanium dioxide loaded stannous oxide composite material; after the esterification reaction is finished, adding a proper amount of water into a reaction product, uniformly mixing, filtering, collecting a catalyst and filtrate, and standing and layering the filtrate to remove a water layer so as to obtain an oil layer; carrying out film evaporation dehydration and deacidification on the oil layer to obtain a cetyl alcohol ethylhexanoate crude product; and carrying out gas stripping on the cetyl alcohol ethyl hexanoate crude product to remove peculiar smell, so as to obtain the cetyl alcohol ethyl hexanoate. According to the preparation method disclosed by the invention, through limitation of a specific catalyst and a process, high-temperature side reaction and generation of pollutants can be effectively reduced, and the purity and yield of the prepared product are improved.

Description

Technical Field

[0001] The present invention relates to the field of synthesis technology, and in particular to a method for preparing cetyl ethylhexanoate. Background Art

[0002] The existing industrial production of cetyl ethylhexanoate usually uses ethylhexanoic acid and cetyl alcohol as raw materials, uses strong acids such as concentrated sulfuric acid and phosphoric acid as catalysts for esterification, and then undergoes vacuum dealcoholization, strong alkali neutralization, water washing, and activated carbon decolorization.

[0003] However, the products obtained by existing technologies have many by-products, low purity, dark color, strong odor, and are unstable during long-term storage; the reaction process uses strong acids and strong bases, the reaction is violent and produces a large amount of sewage and solid waste; the process is intermittent, the production efficiency is low, the operating cost is high, the safety risks are great, and the product quality is unstable, making it difficult to meet market needs. Summary of the Invention

[0004] The object of the present invention is to provide a method for preparing cetyl ethylhexanoate. The preparation method of the present invention can effectively reduce high-temperature side reactions and the generation of pollutants, thereby improving the purity and yield of the prepared product through the limitation of specific catalysts and processes.

[0005] In order to achieve the above-mentioned purpose of the present invention, the following technical solutions are adopted:

[0006] The first aspect of the present invention provides a method for preparing cetyl ethylhexanoate, the method comprising the following steps:

[0007] (a) esterifying ethylhexanoic acid and cetyl alcohol under a catalyst and nitrogen protection conditions, wherein the catalyst is a titanium dioxide-supported stannous oxide composite material;

[0008] (b) After the esterification reaction is completed, water is added to the reaction product, mixed, filtered, the catalyst and the filtrate are collected, and the filtrate is allowed to stand for stratification to remove the water layer to obtain an oil layer;

[0009] (c) subjecting the oil layer to thin film evaporation dehydration and deacidification to obtain a crude product of cetyl ethylhexanoate;

[0010] (d) subjecting the crude product of cetyl ethylhexanoate to gas stripping and deodorization to obtain the cetyl ethylhexanoate.

[0011] Preferably, in step (a), the mass ratio of ethylhexanoic acid to cetyl alcohol is 1:(0.65-2).

[0012] Preferably, in step (a), the amount of catalyst added is 0.005 to 0.015 times the mass of cetyl alcohol.

[0013] Preferably, in step (a), the titanium dioxide-supported stannous oxide composite material is prepared by the following method:

[0014] (1) dissolving a stannous oxide precursor in an anhydrous ethanol solvent to form a uniform solution to obtain a precursor solution;

[0015] (2) adding TiO2 nanoparticles to the precursor solution and stirring for 30 to 60 minutes, allowing to stand, and filtering to obtain titanium dioxide loaded with a stannous oxide precursor;

[0016] (3) drying the titanium dioxide loaded with stannous oxide precursor under nitrogen protection, and then calcining it at 150-200° C. for 40-60 min to obtain the titanium dioxide loaded with stannous oxide composite material.

[0017] Preferably, the ethylhexanoic acid is refluxed during the esterification reaction; the temperature of the esterification reaction is 200-220° C., the pressure is 100-500 mbar, and the reaction is continued until no water is generated.

[0018] Preferably, in step (b), the amount of water added is 0.5 to 5 times the mass of the catalyst.

[0019] Preferably, in step (c), the temperature for dehydration and deacidification is 135-220° C., and the vacuum degree is 1-5 mbar.

[0020] Preferably, in step (d), the temperature of the gas stripping deodorization is 180-220° C., the vacuum degree is 0.5-1 mbar, and the nitrogen volume of the gas stripping tank is 2-5 Nm 3 / hr.

[0021] Compared with the prior art, the beneficial effects of the present invention include at least:

[0022] The preparation method of the present invention adopts a non-acidic catalyst to carry out the catalytic reaction through the limitation of specific catalysts and processes, thereby eliminating the strong base neutralization, water washing and decolorization steps, and avoiding reversible reactions, ester saponification, and the generation of a large amount of sewage and hazardous solid waste. It can effectively reduce high-temperature side reactions, improve the purity and yield of the prepared product, and solve the problems in the prior art of using strong acid catalysts such as sulfuric acid and phosphoric acid, which cause many side reactions at high temperatures, easily oxidize materials and products at high temperatures, and have a dark color. DETAILED DESCRIPTION

[0023] The following embodiments of the technical solution of the present invention are described in detail in conjunction with the embodiments. The following embodiments are only used to more clearly illustrate the technical solution of the present invention and are therefore only used as examples and cannot be used to limit the scope of protection of the present invention.

[0024] It should be noted that, unless otherwise specified, the technical or scientific terms used in this application should have the common meanings understood by those skilled in the art to which the present invention belongs.

[0025] An embodiment of the present invention provides a method for preparing cetyl ethylhexanoate, the method comprising the following steps:

[0026] (a) esterifying ethylhexanoic acid and cetyl alcohol under a catalyst and nitrogen protection conditions, wherein the catalyst is a titanium dioxide-supported stannous oxide composite material;

[0027] (b) After the esterification reaction is completed, water is added to the reaction product, mixed, filtered, the catalyst and the filtrate are collected, and the filtrate is allowed to stand for stratification to remove the water layer to obtain an oil layer;

[0028] (c) subjecting the oil layer to thin film evaporation dehydration and deacidification to obtain a crude product of cetyl ethylhexanoate;

[0029] (d) subjecting the crude product of cetyl ethylhexanoate to gas stripping and deodorization to obtain the cetyl ethylhexanoate.

[0030] The preparation method of the present invention adopts a non-acidic catalyst to carry out the catalytic reaction through the limitation of specific catalysts and processes, thereby eliminating the strong base neutralization, water washing and decolorization steps, and avoiding reversible reactions, ester saponification, and the generation of a large amount of sewage and hazardous solid waste. The mild reaction can effectively reduce high-temperature side reactions, thereby achieving the purpose of preparing a product with high purity and high yield, and solving the problems in the prior art of using strong acid catalysts such as sulfuric acid and phosphoric acid, which result in many side reactions at high temperatures, easy oxidation of materials and products at high temperatures, and dark color.

[0031] In some embodiments, in step (a), the mass ratio of ethylhexanoic acid to cetyl alcohol is 1:(0.65-2).

[0032] In some embodiments, in step (a), the amount of catalyst added is 0.005 to 0.015 times the mass of cetyl alcohol.

[0033] In some embodiments, in step (a), the titanium dioxide-supported stannous oxide composite material is prepared by the following method:

[0034] (1) dissolving a stannous oxide precursor in an anhydrous ethanol solvent to form a uniform solution to obtain a precursor solution;

[0035] (2) adding TiO2 nanoparticles to the precursor solution and stirring for 30 to 60 minutes, allowing to stand, and filtering to obtain titanium dioxide loaded with a stannous oxide precursor;

[0036] (3) drying the titanium dioxide loaded with stannous oxide precursor under nitrogen protection, and then calcining it at 150-200° C. for 40-60 min to obtain the titanium dioxide loaded with stannous oxide composite material.

[0037] In some embodiments, ethylhexanoic acid is refluxed during the esterification reaction; the esterification reaction temperature is 200-220° C., the pressure is 100-500 mbar, and the reaction is carried out until no water is generated.

[0038] In some embodiments, in step (b), the amount of water added is 0.5 to 5 times the mass of the catalyst.

[0039] In some embodiments, in step (c), the temperature for dehydration and deacidification is 135-220° C., and the vacuum degree is 1-5 mbar.

[0040] In some embodiments, in step (d), the temperature of the gas stripping deodorization is 180-220° C., the vacuum degree is 0.5-1 mbar, and the nitrogen volume of the gas stripping tank is 2-5 Nm 3 / hr.

[0041] The technical solution of the present invention is further described in detail below through specific embodiments.

[0042] The titanium dioxide-loaded tin oxide composite materials used in the following examples were prepared by the following method:

[0043] (1) dissolving a stannous oxide precursor (Sn(NO3)2) in an anhydrous ethanol solvent to form a uniform solution to obtain a precursor solution;

[0044] (2) adding TiO2 nanoparticles to the precursor solution and stirring for 50 minutes, allowing to stand, and filtering to obtain titanium dioxide loaded with a stannous oxide precursor; the mass ratio of TiO2 nanoparticles to the stannous oxide precursor is 2:1;

[0045] (3) drying the titanium dioxide loaded with the stannous oxide precursor under nitrogen protection, and then calcining it at 180° C. for 50 min to obtain the titanium dioxide loaded with stannous oxide composite material.

[0046] Example 1

[0047] This embodiment is a preparation method of cetyl ethylhexanoate, which comprises the following steps:

[0048] (a) nitrogen was purged into an esterification reactor, and then 2250 kg of ethylhexanoic acid, 3290 kg of cetyl alcohol, and 16.5 kg of a catalyst were metered in sequence. The mixture was heated to 200° C. under stirring and nitrogen atmosphere to carry out an esterification reaction. No water was generated in the ester. During the esterification reaction, the volatilized ethylhexanoic acid was cooled and refluxed. The reaction pressure was 100 mbar.

[0049] (b) After the esterification reaction is completed, 12 kg of water is added to the reaction product and stirred, and the mixture is filtered through a microfiltration membrane filter to collect the catalyst and the filtrate. The filtrate is allowed to stand for stratification to remove the water layer to obtain an oil layer;

[0050] (c) pumping the oil layer into a thin film evaporator for dehydration and deacidification to obtain a crude product of cetyl ethylhexanoate, wherein the dehydration and deacidification temperature is controlled at 165° C. and the vacuum degree is 5 mbar;

[0051] (d) The crude product of cetyl ethylhexanoate was pumped into a stripping tower and nitrogen was introduced to remove odor. The stripping temperature was controlled at 200°C and the vacuum was 1 mbar. The nitrogen flow rate was 2.5 Nm 3 / hr, the material is removed from the bottom of the stripping tower and cooled to obtain the cetyl ethylhexanoate.

[0052] Example 2

[0053] This embodiment is a preparation method of cetyl ethylhexanoate, which comprises the following steps:

[0054] (a) nitrogen was purged into an esterification reactor, and then 2350 kg of ethylhexanoic acid, 3290 kg of cetyl alcohol, and 16.5 kg of a catalyst were metered in sequence. The mixture was heated to 220° C. under stirring and nitrogen atmosphere to carry out an esterification reaction. No water was generated in the ester. During the esterification reaction, the volatilized ethylhexanoic acid was cooled and refluxed. The reaction pressure was 500 mbar.

[0055] (b) After the esterification reaction is completed, 10 kg of water is added to the reaction product and stirred, and the mixture is filtered through a microfiltration membrane filter to collect the catalyst and the filtrate. The filtrate is allowed to stand for stratification to remove the water layer to obtain an oil layer;

[0056] (c) pumping the oil layer into a thin film evaporator for dehydration and deacidification to obtain a crude product of cetyl ethylhexanoate, wherein the dehydration and deacidification temperature is controlled at 165° C. and the vacuum degree is 5 mbar;

[0057] (d) The crude cetyl ethylhexanoate was pumped into a stripping tower, and nitrogen was introduced to remove odor by stripping. The stripping temperature was controlled at 205° C. and the vacuum was 0.5 mbar. The nitrogen flow rate was 3.5 Nm 3 / hr. The material was removed from the bottom of the stripping tower and cooled to obtain the cetyl ethylhexanoate.

[0058] Example 3

[0059] This embodiment is a preparation method of cetyl ethylhexanoate, which comprises the following steps:

[0060] (a) nitrogen was purged into an esterification reactor, and then 2550 kg of ethylhexanoic acid, 3290 kg of cetyl alcohol, and 20 kg of a catalyst were added in sequence. The mixture was heated to 210° C. under stirring and nitrogen atmosphere to carry out an esterification reaction. No water was generated in the ester. During the esterification reaction, the volatilized ethylhexanoic acid was cooled and refluxed. The reaction pressure was 200 mbar.

[0061] (b) After the esterification reaction is completed, 50 kg of water is added to the reaction product and stirred, and the mixture is filtered through a microfiltration membrane filter to collect the catalyst and the filtrate. The filtrate is allowed to stand for stratification to remove the water layer to obtain an oil layer;

[0062] (c) pumping the oil layer into a thin film evaporator for dehydration and deacidification to obtain a crude product of cetyl ethylhexanoate, wherein the dehydration and deacidification temperature is controlled at 200° C. and the vacuum degree is 5 mbar;

[0063] (d) The crude cetyl ethylhexanoate was pumped into a stripping tower, and nitrogen was introduced to remove odor by stripping. The stripping temperature was controlled at 210° C. and the vacuum was 0.2 mbar. The nitrogen flow rate was 3 Nm 3 / hr. The material was removed from the bottom of the stripping tower and cooled to obtain the cetyl ethylhexanoate.

[0064] Experimental example

[0065] Cetyl ethylhexanoate was prepared according to the preparation methods of Examples 1 to 3 respectively;

[0066] The appearance of the cetyl ethylhexanoate prepared in different examples was observed, and the observation results are shown in Table 1;

[0067] The content, acid value, chromaticity and water content of cetyl ethylhexanoate prepared in different examples were tested, and the test results are shown in Table 1;

[0068] Table 1

[0069]

[0070]

[0071] From Table 1 we can see that:

[0072] The cetyl ethylhexanoate prepared by the preparation method of the embodiment of the present application has high purity, light color and low acid value.

[0073] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or make equivalent replacements for some or all of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present invention, and they should all be included in the scope of the claims and description of the present invention.

Claims

1. A method for preparing cetyl ethylhexanoate, characterized in that: The preparation method comprises the following steps: (a) esterifying ethylhexanoic acid and cetyl alcohol under a catalyst and nitrogen protection conditions, wherein the catalyst is a titanium dioxide-supported stannous oxide composite material; (b) After the esterification reaction is completed, water is added to the reaction product, mixed, filtered, the catalyst and the filtrate are collected, and the filtrate is allowed to stand for stratification to remove the water layer to obtain an oil layer; (c) subjecting the oil layer to thin film evaporation dehydration and deacidification to obtain a crude product of cetyl ethylhexanoate; (d) subjecting the crude product of cetyl ethylhexanoate to gas stripping and deodorization to obtain the cetyl ethylhexanoate.

2. The preparation method according to claim 1, characterized in that In the step (a), the mass ratio of ethylhexanoic acid to cetyl alcohol is 1:(0.65-2).

3. The preparation method according to claim 1, characterized in that In the step (a), the amount of the catalyst added is 0.005 to 0.015 times the mass of cetyl alcohol.

4. The preparation method according to claim 1, characterized in that In the step (a), the titanium dioxide-loaded stannous oxide composite material is prepared by the following method: (1) dissolving a stannous oxide precursor in an anhydrous ethanol solvent to form a uniform solution to obtain a precursor solution; (2) adding TiO2 nanoparticles to the precursor solution and stirring for 30 to 60 minutes, allowing to stand, and filtering to obtain titanium dioxide loaded with a stannous oxide precursor; (3) drying the titanium dioxide loaded with stannous oxide precursor under nitrogen protection, and then calcining it at 150-200° C. for 40-60 min to obtain the titanium dioxide loaded with stannous oxide composite material.

5. The preparation method according to claim 1, characterized in that During the esterification reaction, ethylhexanoic acid is refluxed; the temperature of the esterification reaction is 200-220° C., and the pressure is 100-500 mbar; and the reaction is carried out until no water is generated.

6. The preparation method according to claim 1, characterized in that In the step (b), the amount of water added is 0.5 to 5 times the mass of the catalyst.

7. The preparation method according to claim 1, characterized in that In the step (c), the temperature for dehydration and deacidification is 135-220° C., and the vacuum degree is 1-5 mbar.

8. The preparation method according to claim 1, characterized in that In the step (d), the temperature of the gas stripping deodorization is 180-220°C, the vacuum degree is 0.5-1 mbar, and the nitrogen volume of the gas stripping tank is 2-5 Nm 3 / hr.

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