An acetaldehyde polymerization deterioration product solvent, its preparation method and application

Abstract

The present invention provides an acetaldehyde polymerization deterioration product dissolving agent, a preparation method thereof and an application thereof, and mainly solves the problem that acetaldehyde polymerizes and deteriorates under the action of impurities in an industrial device and then solidifies to block containers and pipelines and cannot flow. The dissolving agent comprises the following components in parts by weight: C 1 -C 4 alcohol 30-70 parts; C 3 -C 6 ketone 10-45 parts; tris(hydroxymethyl)aminomethane 1-10 parts; C 1 -C 4 acid 15-25 parts; inorganic acid 0.5-5 parts. The technical solution provided by the present invention preferably solves this problem, and can be used to dissolve the colloids or solids formed after the deterioration of acetaldehyde, and solve the blockage problems of containers for storing liquid acetaldehyde such as storage tanks and liquid separation tanks, and conveying pipelines.

Description

Technical Field

[0001] The present invention relates to the technical field of petrochemical engineering, and particularly relates to a dissolving agent for acetaldehyde polymerization deterioration products, a preparation method thereof, and an application thereof. Background Art

[0002] As a common chemical raw material, acetaldehyde can be used to produce acetic acid, ethyl acetate, crotonaldehyde, 1,3 - butanediol, pentaerythritol, etc. As a highly chemically active substance, acetaldehyde can undergo an acetal reaction by itself in the presence of trace amounts of acidic impurities, deteriorating to form acetal polymers such as paraldehyde and metaldehyde. In addition, under the stimulation of acidic and alkaline impurities, acetaldehyde can also undergo an aldol condensation reaction to form unsaturated carbonyl compounds such as crotonaldehyde. Unsaturated carbonyl compounds can react with acetaldehyde or further react with each other to form oligomers or even polymers. As the carbon chain grows and the molecular weight increases, the overall viscosity of the acetaldehyde deterioration products increases and the fluidity becomes worse. When the content of the polymer increases to a certain proportion, the product gradually solidifies and loses fluidity.

[0003] In industrial devices such as liquid storage tanks and liquid separation tanks, acetaldehyde is stored and emptied regularly in a liquid state. During storage, liquid acetaldehyde will undergo an aldol condensation reaction under the catalysis of trace impurities, and the deteriorated products formed will have a deeper color, gradually increasing viscosity, and worse fluidity. After deteriorating to a certain extent, it even solidifies and loses fluidity. The deteriorated products cannot be transferred and subsequently processed as liquids, seriously blocking containers and pipelines and affecting the operation of related devices.

[0004] Patent CN111234307A discloses a dissolving agent for polystyrene waste and a preparation method thereof. This method adsorbs the waste from the production of essential oils using camphor trees as raw materials through a macroporous adsorption resin, and then obtains a dissolving agent to dissolve the polystyrene waste. The macroporous adsorption resin is a polar macroporous adsorption resin and / or a non - polar macroporous adsorption resin.

[0005] Patent CN110591123A discloses a dissolving agent for removing cured silicone rubber and a preparation method thereof. The dissolving agent is characterized in that it includes 30% - 60% of C 2 ~C 4 monohydric alcohol or dihydric alcohol, 1% - 8% of strong base, 1% - 10% of dimethyl silicone oil, 1% - 10% of metal slow - release agent, and the balance is solvent oil. This dissolving agent can be used to dissolve and remove cured silicone rubber.

[0006] However, in the existing technology, there is no dissolving agent solution designed for the deterioration products formed by the aldol condensation reaction of acetaldehyde. The problem that the deteriorated products formed after acetaldehyde polymerization have poor fluidity or even solidify and block containers and pipelines has always existed. Summary of the Invention

[0007] In view of the problem that aldol condensation reaction occurs in acetaldehyde itself in the above-mentioned prior art, the fluidity of the deteriorated product is poor and even solidifies, and then the pipeline and container are blocked, one of the purposes of the present invention is to provide a dissolving agent for acetaldehyde polymerization deteriorated product, which can make the acetaldehyde polymerization deteriorated product become liquid for easy treatment.

[0008] Another purpose of the present invention is to provide a preparation method of a dissolving agent for acetaldehyde polymerization deteriorated product corresponding to the first purpose.

[0009] Another purpose of the present invention is to provide an application of a dissolving agent for acetaldehyde polymerization deteriorated product corresponding to the above purposes.

[0010] To achieve the above first purpose, the technical solution adopted by the present invention is as follows:

[0011] A dissolving agent for acetaldehyde polymerization deteriorated product includes the following components by weight:

[0012]

[0013] In some preferred embodiments of the present invention, the C 1 ~C 4 alcohol is selected from at least one of C 1 ~C 4 monohydric alcohol and C 2 ~C 4 polyhydric alcohol, preferably at least one of C 1 ~C 4 monohydric alcohol, more preferably at least one of methanol, ethanol, n-propanol, isopropanol, n-butanol, 2-butanol and 3-butanol, and further preferably at least one of methanol and ethanol.

[0014] According to the present invention, the polyhydric alcohol includes dihydric alcohol, trihydric alcohol and tetrahydric alcohol.

[0015] In some preferred embodiments of the present invention, the C 3 ~C 6 ketone is selected from at least one of acetone, methyl ethyl ketone, 2-pentanone, 3-pentanone and 2-hexanone, preferably acetone.

[0016] In some preferred embodiments of the present invention, the C 1 ~C 4 acid is selected from at least one of C 1 ~C 4 monobasic acid and C 2 ~C 4 polybasic acid, preferably selected from C 1 ~C 4At least one of monobasic acids, more preferably at least one of formic acid, acetic acid, n-propionic acid, n-butyric acid and 2-butyric acid, and further preferably at least one of formic acid and acetic acid.

[0017] According to the present invention, the polybasic acids include dibasic acids, tribasic acids and tetrabasic acids.

[0018] In some preferred embodiments of the present invention, the inorganic acid is selected from at least one of an aqueous sulfuric acid solution with a sulfuric acid concentration of 97 wt% to 99 wt%, an aqueous hydrochloric acid solution with a hydrochloric acid concentration of 33 wt% to 37 wt%, and an aqueous nitric acid solution with a nitric acid concentration of 50 wt% to 70 wt%, and is preferably an aqueous sulfuric acid solution with a sulfuric acid concentration of 97.5 wt% to 98.5 wt%.

[0019] According to the present invention, the C 1 ~C 4 alcohol and the C 1 ~C 4 acid are miscible.

[0020] To achieve the second above object, the technical solution adopted by the present invention is as follows:

[0021] A preparation method of the solvent according to any one of the above embodiments, comprising:

[0022] S1. Mix the C 1 ~C 4 alcohol, the C 3 ~C 6 ketone and the tris(hydroxymethyl)aminomethane to obtain a mixed solution;

[0023] S2. Mix the mixed solution with the C 1 ~C 4 acid and the inorganic acid to obtain a solvent.

[0024] In some preferred embodiments of the present invention, in step S2, the C 1 ~C 4 acid and the inorganic acid are sequentially added to the mixed solution to obtain the solvent.

[0025] According to the present invention, the mixing in steps S1 and S2 is carried out under normal temperature and pressure.

[0026] According to the present invention, to ensure the mixing uniformity, the present invention preferably carries out the mixing under stirring conditions. Stirring is a conventional operation method in the art, and those skilled in the art can select appropriate stirring conditions according to needs.

[0027] According to the present invention, in step S2, the C 1 ~C4 The acid and the inorganic acid are added dropwise.

[0028] According to the present invention, the pH value of the solvent is 3 to 8.

[0029] To achieve the third object, the technical solution adopted by the present invention is as follows:

[0030] Use of a solvent as described in any one of the above embodiments or a solvent prepared by the preparation method described in any one of the above embodiments for dissolving the polymerized and deteriorated product of acetaldehyde. Preferably, the polymerized and deteriorated product of acetaldehyde includes the product of aldol condensation reaction of acetaldehyde.

[0031] In some preferred embodiments of the present invention, the solvent is contacted with the polymerized and deteriorated product of acetaldehyde, or the solvent is added to the acetaldehyde material containing the polymerized and deteriorated product of acetaldehyde.

[0032] In some preferred embodiments of the present invention, the mass ratio of the solvent to the polymerized and deteriorated product of acetaldehyde is (20-40):100; and / or the conditions of the contact include: the temperature is 15°C to 35°C.

[0033] In some preferred embodiments of the present invention, the contact method is stirring or standing, and the time is not limited.

[0034] According to the present invention, the contact method may be soaking, for example, placing the fitting containing the polymerized and deteriorated product of acetaldehyde in the solvent.

[0035] The beneficial effects of the present invention are at least in the following aspects:

[0036] First, the solvent of the present invention itself has a suitable acidity and alkalinity. Through a suitable acid-base input ratio, while ensuring the effect of the solvent, it avoids showing strong acidity or strong alkalinity itself and thus corroding the device and equipment. The preparation method of the solvent itself is convenient, without using expensive reagents, and the cost is low. It can be widely used in the cleaning of related devices, achieving good technical effects.

[0037] Second, the solvent of the present invention, through a suitable solvent blending ratio, obtains a solvent with good solubility for the deteriorated product of acetaldehyde. For the containers or pipelines in which acetaldehyde polymerization and deterioration have occurred in industrial devices, a certain amount of this solvent can be added. After soaking for a certain period of time, the solvent and the polymerized and deteriorated product of acetaldehyde penetrate each other, and the colloidal or solidified deteriorated product gradually dissolves in the solvent, restoring fluidity. The solvent can prevent the blockage of containers and pipelines or dredge the blocked pipelines and containers, facilitating the restoration of the material to a liquid state for subsequent processing. Specific Embodiments

[0038] The present invention will be described in detail below through examples, but the protection scope of the present invention is not limited to the following description.

[0039] For those not specified in the examples, they are carried out according to conventional conditions or the conditions recommended by the manufacturer. For reagents or instruments without indicating the manufacturer, they are all conventional products that can be obtained through commercial channels.

[0040] In the following embodiments, unless otherwise specified, the concentration of concentrated sulfuric acid used is 98 wt%.

[0041] Example 1

[0042] Add 55 g of absolute ethanol and 20 g of acetone to a beaker, and then slowly add 5 g of tris(hydroxymethyl)aminomethane and stir well until completely dissolved.

[0043] Continuously add 18 g of acetic acid to the solution, stir, and slowly add 2 g of concentrated sulfuric acid to obtain a dissolving agent.

[0044] Take 10 g of the product of acetaldehyde polymerization deterioration, the acetaldehyde aldol condensation reaction product, and place it in a beaker. Add 1 g of the dissolving agent thereto, tie the mouth of the beaker with plastic wrap, and place it on a shaker and shake for 6 hours. Take a clean sintered glass crucible, weigh it (weight is m), and place it on a suction flask, connect the vacuum suction filtration device and start it. Pour all the oscillated substances into the sintered glass, maintain the suction filtration state for 30 minutes, then transfer the sintered glass to an oven at 80 °C and store for 12 hours. Take out the sintered glass crucible, cool it, and weigh it (weight is M). Calculate the dissolution efficiency (dissolution rate) through the following formula:

[0045] Dissolution rate = (10 - M + m) / mass of dissolving agent

[0046] The calculated dissolution rate of the dissolving agent is 3.34.

[0047] Example 2

[0048] Add 65 g of absolute ethanol and 10 g of acetone to a beaker, and then slowly add 5 g of tris(hydroxymethyl)aminomethane and stir well until completely dissolved.

[0049] Continuously add 18 g of acetic acid to the solution, stir, and slowly add 2 g of concentrated sulfuric acid to obtain a dissolving agent.

[0050] Test the dissolution rate of the dissolving agent in the same manner as in Example 1, and the result is 3.24.

[0051] Example 3

[0052] Add 30 g of absolute ethanol and 45 g of acetone to a beaker, and then slowly add 5 g of tris(hydroxymethyl)aminomethane and stir well until completely dissolved.

[0053] 18 g of acetic acid was continuously added to the solution, and 2 g of concentrated sulfuric acid was slowly added to prepare a solvent.

[0054] The dissolution rate of the dissolving agent was tested in the same manner as in Example 1 and the result was 3.01.

[0055] Example 4

[0056] Add 55 g of anhydrous ethanol and 20 g of acetone into a beaker, then slowly add 5 g of tris(hydroxymethyl)aminomethane and stir thoroughly until it is completely dissolved.

[0057] 15 g of acetic acid was continuously added to the solution, and 5 g of concentrated sulfuric acid was slowly added to prepare a solvent.

[0058] The dissolution rate of the dissolving agent was tested in the same manner as in Example 1 and the result was 4.01.

[0059] Example 5

[0060] Add 55 g of anhydrous ethanol and 20 g of acetone into a beaker, then slowly add 5 g of tris(hydroxymethyl)aminomethane and stir thoroughly until it is completely dissolved.

[0061] 19.5 g of acetic acid was continuously added to the solution, and 0.5 g of concentrated sulfuric acid was slowly added to prepare a solvent.

[0062] The dissolution rate of the dissolving agent was tested in the same manner as in Example 1 and the result was 3.57.

[0063] Example 6

[0064] The difference between this embodiment and embodiment 1 is that anhydrous methanol is used to replace the anhydrous ethanol in embodiment 1 to prepare the solvent.

[0065] The dissolution rate of the dissolving agent was tested in the same manner as in Example 1 and the result was 3.24.

[0066] Example 7

[0067] The difference between this embodiment and embodiment 1 is that n-butanol is used to replace the anhydrous ethanol in embodiment 1 to prepare the solvent.

[0068] The dissolution rate of the dissolving agent was tested in the same manner as in Example 1 and the result was 2.97.

[0069] Example 8

[0070] The difference between this embodiment and embodiment 1 is that butanone is used to replace the acetone in embodiment 1 to prepare the solvent.

[0071] The dissolution rate of the solvent was tested in the same manner as in Example 1, and the result was 2.42.

[0072] Example 9

[0073] The difference between this example and Example 1 is only that n-butyric acid is used to replace acetic acid in Example 1 to prepare the solvent.

[0074] The dissolution rate of the solvent was tested in the same manner as in Example 1, and the result was 2.93.

[0075] Example 10

[0076] The difference between this example and Example 1 is only that concentrated hydrochloric acid with a concentration of 37 wt% is used to replace concentrated sulfuric acid in Example 1 to prepare the solvent.

[0077] The dissolution rate of the solvent was tested in the same manner as in Example 1, and the result was 1.31.

[0078] Example 11

[0079] The difference between this example and Example 1 is only that concentrated nitric acid with a concentration of 70 wt% is used to replace concentrated sulfuric acid in Example 1 to prepare the solvent.

[0080] The dissolution rate of the solvent was tested in the same manner as in Example 1, and the result was 2.70.

[0081] Comparative Example 1

[0082] The difference between this example and Example 1 is only that ethanol is used to replace the solvent in Example 1 to test the solvent, and the result was 0.89.

[0083] Comparative Example 2

[0084] The difference between this example and Example 1 is only that acetic acid is used to replace the solvent in Example 1 to test the solvent, and the result was 1.27.

[0085] Comparative Example 3

[0086] The difference between this example and Example 1 is only that water is used to replace the solvent in Example 1 to test the solvent, and the result was 0.05.

[0087] Comparative Example 4

[0088] 75 g of absolute ethanol was added to a beaker, and then 5 g of tris(hydroxymethyl)aminomethane was slowly added and stirred thoroughly until completely dissolved.

[0089] 20 g of acetic acid was continuously added to the solution and stirred to prepare the solvent.

[0090] The dissolution rate of the solvent was tested in the same manner as in Example 1, and the result was 1.5.

[0091] It should be noted that the above-described embodiments are only used to explain the present invention and do not constitute any limitation to the present invention. The present invention has been described by reference to the exemplary embodiments, but it should be understood that the words used therein are descriptive and explanatory words rather than limiting words. Modifications may be made to the present invention within the scope of the claims of the present invention as provided, and revisions may be made to the present invention without departing from the scope and spirit of the present invention. Although the present invention described therein relates to specific methods, materials and embodiments, it does not mean that the present invention is limited to the specific examples disclosed therein. On the contrary, the present invention can be extended to all other methods and applications having the same function.

Claims

1. An acetaldehyde polymerization deterioration product dissolving agent, comprising the following components by weight parts: The inorganic acid is selected from at least one of an aqueous sulfuric acid solution with a sulfuric acid concentration of 97wt% - 99wt%, an aqueous hydrochloric acid solution with a hydrochloric acid concentration of 33wt% - 37wt%, and an aqueous nitric acid solution with a nitric acid concentration of 50wt% - 70wt%.

2. The dissolving agent according to claim 1, characterized in that, by weight parts, the dissolving agent comprises the following components:

3. The dissolving agent according to claim 1 or 2, characterized in that, The said C 1 ~C 4 The alcohol is selected from C 1 ~C 4 monohydric alcohols and C 2 ~C 4 at least one of polyhydric alcohols.

4. The dissolving agent according to claim 3, characterized in that, The C 1 ~C 4 alcohol is selected from at least one of C 1 ~C 4 monohydric alcohols.

5. The dissolving agent according to claim 4, characterized in that, The said C 1 ~C 4 The alcohol is selected from at least one of methanol, ethanol, n-propanol, isopropanol, n-butanol, 2-butanol, and 3-butanol.

6. The dissolving agent according to claim 5, characterized in that, The said C 1 ~C 4 The alcohol is selected from at least one of methanol and ethanol.

7. The dissolving agent according to claim 1 or 2, characterized in that, The C 3 ~C 6 ketone is selected from at least one of acetone, methyl ethyl ketone, 2-pentanone, 3-pentanone and 2-hexanone.

8. The dissolving agent according to claim 7, characterized in that, Said C 3 ~C 6 The ketone is acetone.

9. The dissolving agent according to claim 1 or 2, characterized in that, The said C 1 ~C 4 The acid is selected from C 1 ~C 4 monobasic acids and C 2 ~C 4 at least one of polybasic acids.

10. The dissolving agent according to claim 9, characterized in that, The said C 1 to C 4 acid is selected from at least one of C 1 to C 4 monobasic acids.

11. The dissolving agent according to claim 10, characterized in that, The said C 1 ~C 4 acid is selected from at least one of formic acid, acetic acid, n-propionic acid, n-butyric acid and 2-butyric acid.

12. The dissolving agent according to claim 11, characterized in that, The C 1 ~C 4 acid is selected from at least one of formic acid and acetic acid.

13. The dissolving agent according to claim 1 or 2, characterized in that, the inorganic acid is selected from an aqueous sulfuric acid solution with a sulfuric acid concentration of 97.5wt% - 98.5wt%.

14. A preparation method of the dissolving agent according to any one of claims 1 - 13, comprising: S1. Mix the C 1 -C 4 alcohol, the C 3 -C 6 ketone and the tris(hydroxymethyl)aminomethane to obtain a mixed solution; S2. Mix the mixed solution with the C 1 ~C 4 acid and the inorganic acid to obtain a dissolving agent.

15. The preparation method according to claim 14, characterized in that, In step S2, the C 1 -C 4 acid and the inorganic acid are successively added to the mixed solution to obtain the dissolving agent.

16. An application of the dissolving agent according to any one of claims 1 - 13 or the dissolving agent prepared by the preparation method according to claim 14 or 15 in dissolving an acetaldehyde polymerization deterioration product.

17. The application according to claim 16, characterized in that, the acetaldehyde polymerization deterioration product includes an acetaldehyde aldol condensation reaction product.

18. The application according to claim 16 or 17, characterized in that, bringing the dissolving agent into contact with the acetaldehyde polymerization deterioration product, or adding the dissolving agent to an acetaldehyde material containing an acetaldehyde polymerization deterioration product.

19. The application according to claim 16 or 17, characterized in that, the mass ratio of the dissolving agent to the acetaldehyde polymerization deterioration product is (20 - 40):100; and / or the conditions of the contact include: the temperature is 15°C - 35°C.

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