Application of Ethylene Oxide in Inhibiting Acetaldehyde Polymerization

Abstract

The present invention discloses the application of ethylene oxide in inhibiting the polymerization of acetaldehyde. The present invention adds ethylene oxide to acetaldehyde and tests the amount of trimeraldehyde generated after a period of time. It is first discovered that ethylene oxide can be added to acetaldehyde as an antacid to reduce the acidity of acetaldehyde and prevent it from generating acidic substances for a long time, thereby inhibiting the polymerization of acetaldehyde during storage and transportation; and ethylene oxide does not react with acetaldehyde under normal conditions, thereby avoiding affecting the quality of acetaldehyde.

Description

Technical Field

[0001] The invention belongs to the field of acetaldehyde storage and transportation, and particularly relates to the application of ethylene oxide in inhibiting acetaldehyde polymerization. Background Art

[0002] In the process of preparing acetaldehyde from ethanol, polymerization reaction easily occurs due to the instability of acetaldehyde. Polymerization reaction also occurs during the storage and transportation of acetaldehyde to produce trimeraldehyde.

[0003] In the prior art, in order to inhibit acetaldehyde polymerization, ammonium acetate is usually added to acetaldehyde as an inhibitor, but the amount of ammonium acetate added is usually high, and adding more than 30 ppm of ammonium acetate will affect the quality of acetaldehyde. In view of this, it is urgent to develop a suitable measure to inhibit acetaldehyde polymerization without affecting the quality of acetaldehyde. Summary of the invention

[0004] In view of the shortcomings of the prior art, the present invention aims to provide an application of ethylene oxide in inhibiting the polymerization of acetaldehyde. By adding ethylene oxide as a polymerization inhibitor to acetaldehyde, the acetaldehyde quality is not affected and the polymerization of acetaldehyde can be well inhibited.

[0005] To achieve the above object, the present invention is implemented through the following technical solutions:

[0006] The invention provides application of ethylene oxide in inhibiting acetaldehyde polymerization.

[0007] Furthermore, ethylene oxide reduces the acidity of acetaldehyde by reacting with the acid in acetaldehyde, thereby inhibiting the polymerization of acetaldehyde.

[0008] Since organic acids and inorganic acids are the most unavoidable in the daily production of acetaldehyde, further, the above acid is an organic acid and / or an inorganic acid. The inorganic acid is usually hydrochloric acid and / or sulfuric acid, and the organic acid is formic acid.

[0009] Furthermore, the use of ethylene oxide in inhibiting acetaldehyde polymerization includes: adding a certain amount of ethylene oxide to the acetaldehyde raw material, then sealing it, and storing or transporting it in a low temperature environment.

[0010] Furthermore, the low temperature environment is 10-15°C.

[0011] More preferably, the low temperature environment is 10°C.

[0012] Furthermore, the amount of ethylene oxide added is 30 to 50 ppm.

[0013] More preferably, the amount of ethylene oxide added is 30 ppm.

[0014] The invention also provides a compounding agent for inhibiting acetaldehyde polymerization, wherein the compounding agent contains ethylene oxide.

[0015] The beneficial effects of the present invention are:

[0016] The present invention adds ethylene oxide to acetaldehyde and tests the generated amount of trimeraldehyde after a period of time. It is found for the first time that ethylene oxide can be added to acetaldehyde as an antacid to reduce the acidity of acetaldehyde and prevent it from generating acidic substances for a long time, thereby inhibiting the polymerization of acetaldehyde during storage and transportation. Moreover, ethylene oxide does not react with acetaldehyde under normal conditions, thereby avoiding affecting the quality of acetaldehyde. DETAILED DESCRIPTION

[0017] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0018] The embodiment of the present invention provides the use of ethylene oxide in inhibiting acetaldehyde polymerization, comprising: adding 30-50 ppm of ethylene oxide to acetaldehyde raw material, then sealing, and storing or transporting at a low temperature of 10-15°C.

[0019] Example 1

[0020] Pure acetaldehyde (99.8%, industrial product) was placed in a constant temperature environment of 10°C for 24 hours and then sampled and analyzed. The acetaldehyde content in the sample remained basically unchanged, still at around 99.8%, and no new acetaldehyde was observed, indicating that acetaldehyde itself would not undergo self-polymerization reaction without adding any other substances.

[0021] Example 2

[0022] During the experiment, the reaction container was first placed in a refrigerator to cool, and then 1000 ml of the finished acetaldehyde raw material was taken out and added. 10 ppm of hydrochloric acid was added to the reaction container through the small hole in the bottle cap with a micro-injector. After the reaction container was fully shaken, it was quickly placed in a constant temperature environment of 10°C. After the reaction proceeded to a predetermined time, a sample was taken through the micro-hole in the bottle cap, and the content of triacetaldehyde in the sample was analyzed by gas chromatography. The results are recorded in Table 1.

[0023] Table 1 Effect of hydrochloric acid on acetaldehyde catalytic polymerization

[0024]

[0025] It can be seen that hydrochloric acid has an obvious catalytic effect on the polymerization reaction of acetaldehyde.

[0026] Example 3

[0027] During the experiment, the reaction container was first placed in a refrigerator to cool, and then 1000 ml of the finished acetaldehyde raw material was taken out and added, and 30 ppm of ethylene oxide was added and then sealed. 10 ppm of hydrochloric acid was added to the reaction container through the small hole in the bottle cap with a micro-injector. After the reaction container was fully shaken, it was quickly placed in a constant temperature environment of 10°C. After the reaction proceeded to a predetermined time, a sample was taken through the micro-hole in the bottle cap, and the content of triacetaldehyde in the sample was analyzed by gas chromatography. The results are recorded in Table 2.

[0028] Table 2 Inhibition of 30ppm ethylene oxide on acetaldehyde self-polymerization

[0029]

[0030] It can be seen that ethylene oxide has a significant inhibitory effect on the acetaldehyde polymerization reaction, and the acetaldehyde content in the system will not decrease after 48 hours, and no other impurities will be generated.

[0031] Example 4

[0032] During the experiment, the reaction container was first placed in a refrigerator to cool, and then 1000 ml of the finished acetaldehyde raw material was taken out and added, and 50 ppm of ethylene oxide was added and then sealed. 10 ppm of hydrochloric acid was added to the reaction container through the small hole in the bottle cap with a micro-injector. After the reaction container was fully shaken, it was quickly placed in a constant temperature environment of 10°C. After the reaction was carried out for a predetermined time, a sample was taken through the micro-hole in the bottle cap, and the content of triacetaldehyde in the sample was analyzed by gas chromatography. The results are recorded in Table 3.

[0033] Table 3 Inhibition effect of 50ppm ethylene oxide on acetaldehyde self-polymerization

[0034]

[0035] It can be seen that ethylene oxide has a significant inhibitory effect on the acetaldehyde polymerization reaction. After adding 50 ppm ethylene oxide into the system, the rate of acetaldehyde self-polymerization to produce trimeraldehyde decreases, the growth rate of trimeraldehyde content is very slow, and the acetaldehyde content in the system will not decrease after 48 hours, and no other impurities are generated.

[0036] Comparative Example 1

[0037] During the experiment, the reaction container was first placed in a refrigerator to cool, and then 1000 ml of the finished acetaldehyde raw material was taken out and added, and 30 ppm of ammonium acetate was added and then sealed. 10 ppm of hydrochloric acid was added to the reaction container through the small hole in the bottle cap with a micro-injector. After the reaction container was fully shaken, it was quickly placed in a constant temperature environment of 10°C. After the reaction was carried out for a predetermined time, a sample was taken through the micro-hole in the bottle cap, and the content of triacetaldehyde in the sample was analyzed by gas chromatography. The results are recorded in Table 4.

[0038] Table 4 Inhibition of 30ppm ammonium acetate on acetaldehyde self-polymerization

[0039]

[0040] Comparative Example 2

[0041] During the experiment, the reaction container was first placed in a refrigerator to cool, and then 1000 ml of the finished acetaldehyde raw material was taken out and added, and 50 ppm of ammonium acetate was added and then sealed. 10 ppm of hydrochloric acid was added to the reaction container through the small hole in the bottle cap with a micro-injector. After the reaction container was fully shaken, it was quickly placed in a constant temperature environment of 10°C. After the reaction proceeded to a predetermined time, a sample was taken through the micro-hole in the bottle cap, and the content of triacetaldehyde in the sample was analyzed by gas chromatography. The results are recorded in Table 5.

[0042] Table 5 Inhibition of 50ppm ammonium acetate on acetaldehyde self-polymerization

[0043]

[0044] It can be seen from the results of Examples 1 to 4 that pure acetaldehyde itself will not polymerize, and hydrochloric acid has a significant catalytic effect on the polymerization reaction of acetaldehyde. When ethylene oxide is added, the ethylene oxide reacts with the acid to reduce the acidity of acetaldehyde and prevent it from producing acidity for a long time, thereby inhibiting the polymerization of acetaldehyde.

[0045] It can be seen from Examples 3 to 4 and Comparative Examples 1 to 2 that ethylene oxide has a better inhibitory effect on acetaldehyde polymerization than ammonium acetate, and it is found that after adding ammonium acetate for 48 hours, in addition to inhibiting polymerization, other impurities are produced in the sample, which reduces the acetaldehyde content and affects the quality of acetaldehyde; while ethylene oxide not only has a certain inhibitory effect on acetaldehyde polymerization but also has little effect on the quality of acetaldehyde.

[0046] The present invention also explores that when an organic acid such as formic acid is added to acetaldehyde, ethylene oxide also has an inhibitory effect on acetaldehyde polymerization, which is similar to the inhibitory effect when hydrochloric acid is added to the system. Since the catalytic effect of formic acid on acetaldehyde polymerization is much weaker than that of hydrochloric acid, the present invention will not go into details here.

[0047] In summary, the present invention explores the causes of acetaldehyde polymerization and the application of ethylene oxide in inhibiting acetaldehyde polymerization. By adding ethylene oxide to acetaldehyde, it is ensured that acetaldehyde will not undergo polymerization reaction during storage and transportation, and no other impurities are generated, which effectively solves the safety problems caused by acetaldehyde polymerization during storage and transportation.

[0048] It should be noted that the above embodiments all belong to the same inventive concept, and the description of each embodiment has its own focus. For matters that are not described in detail in some embodiments, reference may be made to the description in other embodiments.

[0049] The above-mentioned embodiments only express the implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. The use of ethylene oxide in inhibiting acetaldehyde polymerization, characterized in that: The ethylene oxide reduces the acidity of acetaldehyde by reacting with the acid in acetaldehyde, thereby inhibiting the polymerization of acetaldehyde; The acid is an organic acid and / or an inorganic acid; a certain amount of ethylene oxide is added to the acetaldehyde raw material, which is then sealed and stored or transported in a low-temperature environment; the low-temperature environment is 10-15°C; and the amount of ethylene oxide added is 30-50ppm.

2. The use of ethylene oxide in inhibiting acetaldehyde polymerization according to claim 1, characterized in that: The inorganic acid is hydrochloric acid and / or sulfuric acid; the organic acid is formic acid.

3. The use of ethylene oxide in inhibiting acetaldehyde polymerization according to claim 1, characterized in that: The low temperature environment is 10°C.

4. The use of ethylene oxide in inhibiting acetaldehyde polymerization according to claim 1, characterized in that: The added amount of ethylene oxide is 30 ppm.

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