Polymerization inhibitor applied to butadiene refining process and preparation method thereof

Abstract

The invention provides a polymerization inhibitor applied to a butadiene refining process, which is prepared from the following components in parts by weight: 5 to 10 parts of free trapping agent, 3 to 6 parts of organic sulfonic acid amine salt, 2 to 8 parts of aromatic amine, 65 to 85 parts of C10 aromatic hydrocarbon and 4 to 8 parts of alkylphenol, the free trapping agent is polystyrene microsphere modified piperidine nitroxide free radicals; the organic sulfonic acid amine salt is dihydroxy propanesulfonic acid amine salt; the aromatic amine is one or a mixture of N-methylaniline, N, N-dimethylaniline and benzidine; and the alkylphenol is one or a mixture of 2, 6-di-tert-butyl-4-methylphenol and 4-tert-butylcatechol.

Description

Technical Field

[0001] The invention belongs to the technical field of petrochemical polymerization inhibitors, and specifically relates to a polymerization inhibitor used in a butadiene refining process and a preparation method thereof. Background Art

[0002] Butadiene is an important chemical raw material. It is an unsaturated hydrocarbon with two carbon-carbon double bonds (=C=C=). It has typical olefin reaction characteristics and can participate in a variety of chemical reactions, such as polymerization reactions, addition reactions, etc. It is mainly used in the synthesis of styrene-butadiene rubber, butadiene rubber, nitrile rubber, chloroprene rubber and other polymers.

[0003] Butadiene is mainly produced by the following methods: Pyrolysis gasoline extraction: butadiene is extracted from the mixture produced by petroleum cracking. Ethanol dehydration: butadiene is produced by the dehydration reaction of ethanol at high temperature. Direct dehydrogenation: butadiene is produced by the dehydrogenation reaction of n-butane or n-butene under the action of a catalyst. Butadiene is prone to spontaneous polymerization due to its highly active double bond structure. It is easy to undergo unplanned polymerization during storage, transportation and processing. Therefore, inhibitors are needed to control its polymerization behavior in industrial applications.

[0004] At present, most of them are compounded by piperidine nitroxide free radical polymerization inhibitor and other organic retarders. Piperidine nitroxide free radical polymerization inhibitor and substituted hydrocarbon amine polymerization inhibitor have the advantages of high temperature resistance, low temperature, no corrosion and polymerization inhibition in both gas and liquid. However, due to the high price of hydrocarbon amine and piperidine, and the high volatility of these two compounds at high temperature, they have large resistance, high energy consumption and increased cost. Summary of the invention

[0005] The invention aims to provide a polymerization inhibitor used in the refining process of butadiene and a preparation method thereof. The polymerization inhibitor is prepared by using a free capture agent, an organic sulfonic acid amine salt, an aromatic amine, a C10 aromatic hydrocarbon and an alkylphenol, and has multiple functions such as polymerization inhibition, dispersion and passivation, and can effectively inhibit the polymerization of butadiene.

[0006] In order to achieve the above object, the present invention provides the following technical solutions: A polymerization inhibitor used in the butadiene refining process comprises the following components by weight: 5-10 parts of a free capture agent, 3-6 parts of an organic sulfonic acid amine salt, 2-8 parts of an aromatic amine, 65-85 parts of C10 aromatic hydrocarbons and 4-8 parts of an alkylphenol.

[0007] Preferably, the free capture agent is a polystyrene microsphere modified piperidine nitrogen oxide free radical; the organic sulfonic acid amine salt is a dihydroxypropanesulfonic acid amine salt; the aromatic amine is one of N-methylaniline, N,N-dimethylaniline and benzidine or a mixture; the alkylphenol is one of 2,6-di-tert-butyl-4-methylphenol and 4-tert-butylcatechol or a mixture.

[0008] Preferably, the aromatic amine is a mixture of N-methylaniline and benzidine, and the mass ratio of the two is 1:1.5-2.5.

[0009] Preferably, the alkylphenol is a mixture of 2,6-di-tert-butyl-4-methylphenol and 4-tert-butylcatechol, and the mass ratio of the two is 2-3:1.

[0010] A method for preparing a polymerization inhibitor used in a butadiene refining process comprises the following steps: S1: Preparation of polystyrene microspheres; S2; preparing a free capture agent; S3: preparing organic sulfonic acid amine salt; S4: by weight, 5-10 parts of the free capture agent obtained in step S2, 3-6 parts of the organic sulfonic acid amine salt obtained in step S3 and 65-85 parts of C10 aromatic hydrocarbons are mixed and stirred to obtain a mixed solution A; S5: Add 2-8 parts of aromatic amine and 4-8 parts of alkyl phenol to the mixed solution A obtained in step S4, and mix and stir to obtain a polymerization inhibitor.

[0011] Preferably, step S1 is specifically as follows: 30-60 parts of styrene, 0.5-1.5 parts of potassium persulfate and 8-12 parts of 2-5 mol / L sodium chloride aqueous solution are mixed, and polymerization reaction is carried out at a temperature of 70-90° C. for 8-10 hours in the presence of nitrogen to obtain a microsphere emulsion; and polystyrene microspheres are obtained by centrifugation, washing with distilled water and drying.

[0012] Preferably, step S2 is specifically as follows: 8-12 parts of 4-hydroxy-2,2,6,6-tetramethylpiperidinyl nitroxide free radical, 3-5 parts of polystyrene microspheres and 15-25 parts of cedarwood alcohol are mixed, and ultrasonically treated at 75-85° C. and 1000-1200 W for 25-45 min to obtain a free capture agent.

[0013] Preferably, step S3 is specifically as follows: 20-40 parts of sodium 1-chloro-2-hydroxy-3-propanesulfonate, 6-10 parts of anhydrous sodium carbonate, and 40-60 parts of water are mixed, and stirred at a temperature of 90-100° C. for 2-4 hours to obtain sodium dihydroxypropanesulfonate.

[0014] Preferably, in step S4, the reaction is stirred at a temperature of 45-65° C. and a rate of 450-550 r / min for 30-50 min.

[0015] Preferably, in step S5, the reaction is stirred at a temperature of 70-90° C. and a rate of 500-600 r / min for 1.5-3.5 h.

[0016] Compared with the prior art, the advantages and beneficial effects of the present invention are: The invention uses 4-hydroxy-2,2,6,6-tetramethylpiperidinyl nitroxide free radicals, polystyrene microspheres and cedar alcohol to obtain a free radical scavenger, which can quickly react with the free radicals of the material to prevent the oxidative polymerization of butadiene; under the synergistic effect of organic sulfonic acid amine salts, aromatic amines and alkylphenols, it can effectively remove polymerization initiators such as free radicals and oxygen, eliminate the activity of the polymer in the polymerization process, and thus achieve the effect of effectively inhibiting the polymerization of butadiene. DETAILED DESCRIPTION

[0017] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. 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 raw materials used in the present invention are as follows: Styrene was from Jinan Aochen Chemical Co., Ltd., item number 592; 4-hydroxy-2,2,6,6-tetramethylpiperidinyl nitroxide free radical was from Shanghai Yuanye Biotechnology Co., Ltd., item number S44698; cedarwood alcohol was from Shanghai Puyouwen Biotechnology Co., Ltd., item number P0682; C10 aromatics was from Nanjing Kewen Chemical Co., Ltd., item number 2; and benzidine was from Shanghai Yuanye Biotechnology Co., Ltd., item number B72878.

[0019] Example 1 This embodiment provides a method for preparing a polymerization inhibitor used in a butadiene refining process, comprising the following steps: S1: 30g of styrene, 0.5g of potassium persulfate and 8g of 2mol / L sodium chloride aqueous solution were mixed, and polymerized at 70°C for 8h in the presence of nitrogen to obtain a microsphere emulsion; the microspheres were obtained by centrifugal separation, washing with distilled water and drying; S2: 8 g of 4-hydroxy-2,2,6,6-tetramethylpiperidinyl nitroxide free radical, 3 g of polystyrene microspheres and 15 g of cedarwood alcohol were mixed and ultrasonically treated at 75°C and 1000W for 25 min to obtain a free capture agent; S3: 20 g of sodium 1-chloro-2-hydroxy-3-propanesulfonate, 6 g of anhydrous sodium carbonate and 40 g of water were mixed, and the mixture was stirred at 90° C. and 500 r / min for 2 h to obtain sodium dihydroxypropanesulfonate; S4: 5 g of the free capture agent obtained in step S2, 3 g of sodium dihydroxypropanesulfonate amide obtained in step S3 and 65 g of C10 aromatic hydrocarbon were mixed and stirred, and reacted at a temperature of 45° C. and a speed of 450 r / min for 30 min to obtain a mixed solution A; S5: Add 2 g of aromatic amine (the aromatic amine is a mixture of N-methylaniline and benzidine, with a mass ratio of 1:1.5) and 4 g of alkylphenol (a mixture of 2,6-di-tert-butyl-4-methylphenol and 4-tert-butylcatechol, with a mass ratio of 2:1) to the mixed solution A obtained in step S4, mix and stir, and react at a temperature of 70°C and a speed of 500 r / min for 1.5 h to obtain an inhibitor.

[0020] Example 2 This embodiment provides a method for preparing a polymerization inhibitor used in a butadiene refining process, comprising the following steps: S1: 60g of styrene, 1.5g of potassium persulfate and 12g of 5mol / L sodium chloride aqueous solution were mixed, and polymerized at 90°C for 10h in the presence of nitrogen to obtain a microsphere emulsion; the microspheres were obtained by centrifugal separation, washing with distilled water and drying; S2: 12 g of 4-hydroxy-2,2,6,6-tetramethylpiperidinyl nitroxide free radical, 5 g of polystyrene microspheres and 25 g of cedarwood alcohol were mixed and ultrasonically treated at 85°C and 1200W for 45 min to obtain a free capture agent; S3: 40 g of sodium 1-chloro-2-hydroxy-3-propanesulfonate, 10 g of anhydrous sodium carbonate and 60 g of water were mixed, and stirred at 100° C. for 4 h to obtain sodium dihydroxypropanesulfonate; S4: 10 g of the free capture agent obtained in step S2, 6 g of the organic sulfonic acid amine salt obtained in step S3 and 85 g of C10 aromatic hydrocarbon were mixed and stirred, and reacted at a temperature of 65° C. and a speed of 550 r / min for 50 min to obtain a mixed solution A; S5: Add 8 g of aromatic amine (the aromatic amine is a mixture of N-methylaniline and benzidine, and the mass ratio of the two is 1:2.5) and 8 g of alkylphenol (the alkylphenol is a mixture of 2,6-di-tert-butyl-4-methylphenol and 4-tert-butylcatechol, and the mass ratio of the two is 3:1) to the mixed solution A obtained in step S4, mix and stir, and stir at a temperature of 90°C and a speed of 600 r / min for 3.5 hours to obtain an inhibitor.

[0021] Example 3 This embodiment provides a method for preparing a polymerization inhibitor used in a butadiene refining process, comprising the following steps: S1: 45g of styrene, 1.2g of potassium persulfate and 9g of 3mol / L sodium chloride aqueous solution were mixed, and polymerized at 85°C for 9h in the presence of nitrogen to obtain a microsphere emulsion; the microspheres were obtained by centrifugation, washing with distilled water and drying; S2: 10 g of 4-hydroxy-2,2,6,6-tetramethylpiperidinyl nitroxide free radical, 4 g of polystyrene microspheres and 22 g of cedarwood alcohol were mixed and ultrasonically treated at 80°C and 1100W for 40 min to obtain a free capture agent; S3: 35 g of sodium 1-chloro-2-hydroxy-3-propanesulfonate, 7 g of anhydrous sodium carbonate and 55 g of water were mixed, and the mixture was stirred at 95° C. and 600 r / min for 3.5 h to obtain sodium dihydroxypropanesulfonate; S4: 7 g of the free capture agent obtained in step S2, 5 g of the organic sulfonic acid amine salt obtained in step S3 and 80 g of C10 aromatic hydrocarbon were mixed and stirred, and reacted at a temperature of 55° C. and a speed of 500 r / min for 45 min to obtain a mixed solution A; S5: Add 6 g of aromatic amine and 7 g of alkylphenol to the mixed solution A obtained in step S4, mix and stir, and react at a temperature of 85° C. and a speed of 550 r / min for 3 h to obtain an inhibitor.

[0022] Comparative Example 1 The difference between this comparative example and Example 1 is that step S1 is missing, that is, polystyrene microspheres are not added for modification, and the other steps are the same.

[0023] Comparative Example 2 The difference between this comparative example and Example 1 is that cedarwood alcohol is not added in step S2, and the other steps are the same.

[0024] Comparative Example 3 The difference between this comparative example and Example 1 is that step S3 is missing, that is, organic sulfonic acid amine salt is not added, and the other steps are the same.

[0025] Comparative Example 4 The difference between this comparative example and Example 1 is that alkylphenol is missing in step S5, and the other steps are the same.

[0026] Comparative Example 5 The difference between this comparative example and Example 1 is that the aromatic amine in step S5 is N-methylaniline, and the other steps are the same.

[0027] Comparative Example 6 The difference between this comparative example and Example 1 is that the alkylphenol in step S5 is 2,6-di-tert-butyl-4-methylphenol, and the other steps are the same.

[0028] Performance Testing: A packed tower with a reflux pipe at the top and a raw material supply pipe and an extractant supply pipe in the middle is used for extractive distillation of crude butadiene. The raw material supplied is cracked C4 containing 44-47% butadiene, the extractant is dimethylformamide, the tower top temperature is 41°C, the tower bottom temperature is 135°C, and the tower operating pressure is 3.5kg / cm 2 The inhibitors of the embodiments and comparative examples were dissolved in the reflux line at the top of the tower. The amount of the inhibitor was 0.07% of the total amount of butadiene. The partial reflux method was adopted. After 10 hours of continuous operation, the polymer produced in the tower was dried under reduced pressure to a constant weight and the weight of the polymer was measured. The results are shown in the following table: Table 1 Performance test results

[0029] From the above performance test results, it can be seen that, under the action of the polymerization inhibitor of this aspect, Examples 1-3 significantly reduce the amount of butadiene polymer produced through the synergistic polymerization inhibition effect, showing the excellent polymerization inhibition effect of the composite polymerization inhibitor; in particular, the comprehensive performance of Example 3 is the most outstanding. However, since Comparative Examples 1-6 do not adopt the necessary technical solutions, their corresponding performance tests are significantly worse than those of the embodiments. The above experimental results further prove the importance of the technical solutions defined in the present invention for its technical effects.

[0030] The above is a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A polymerization inhibitor used in a butadiene refining process, characterized in that: The invention comprises the following components in parts by weight: 5-10 parts of free capture agent, 3-6 parts of organic sulfonic acid amine salt, 2-8 parts of aromatic amine, 65-85 parts of C10 aromatic hydrocarbon and 4-8 parts of alkylphenol.

2. The polymerization inhibitor used in the butadiene refining process according to claim 1, characterized in that: The free capture agent is a polystyrene microsphere modified piperidine nitrogen oxide free radical; the organic sulfonic acid amine salt is a dihydroxypropanesulfonic acid amine salt; the aromatic amine is one of N-methylaniline, N,N-dimethylaniline and benzidine or a mixture thereof; the alkylphenol is one of 2,6-di-tert-butyl-4-methylphenol and 4-tert-butylcatechol or a mixture thereof.

3. The polymerization inhibitor used in the butadiene refining process according to claim 1, characterized in that: The aromatic amine is a mixture of N-methylaniline and benzidine, and the mass ratio of the two is 1:1.5-2.

5.

4. The polymerization inhibitor used in the butadiene refining process according to claim 1, characterized in that: The alkylphenol is a mixture of 2,6-di-tert-butyl-4-methylphenol and 4-tert-butylcatechol, and the mass ratio of the two is 2-3:

1.

5. A method for preparing a polymerization inhibitor used in a butadiene refining process, characterized in that: The steps include: S1: Preparation of polystyrene microspheres; S2; preparing a free capture agent; S3: preparing organic sulfonic acid amine salt; S4: by weight, 5-10 parts of the free capture agent obtained in step S2, 3-6 parts of the organic sulfonic acid amine salt obtained in step S3 and 65-85 parts of C10 aromatic hydrocarbons are mixed and stirred to obtain a mixed solution A; S5: Add 2-8 parts of aromatic amine and 4-8 parts of alkyl phenol to the mixed solution A obtained in step S4, and mix and stir to obtain a polymerization inhibitor.

6. The method for preparing a polymerization inhibitor used in a butadiene refining process according to claim 3, characterized in that: Step S1 is specifically as follows: 30-60 parts of styrene, 0.5-1.5 parts of potassium persulfate and 8-12 parts of 2-5 mol / L sodium chloride aqueous solution are mixed, and polymerization reaction is carried out at 70-90° C. for 8-10 hours in the presence of nitrogen to obtain a microsphere emulsion; and polystyrene microspheres are obtained by centrifugal separation, washing with distilled water and drying.

7. The method for preparing a polymerization inhibitor used in a butadiene refining process according to claim 3, characterized in that: Step S2 is specifically as follows: 8-12 parts of 4-hydroxy-2,2,6,6-tetramethylpiperidinyl nitroxide free radical, 3-5 parts of polystyrene microspheres and 15-25 parts of cedarwood alcohol are mixed, and ultrasonically treated at 75-85° C. and 1000-1200 W for 25-45 minutes to obtain a free capture agent.

8. The method for preparing a polymerization inhibitor used in a butadiene refining process according to claim 3, characterized in that: Step S3 is specifically as follows: 20-40 parts of sodium 1-chloro-2-hydroxy-3-propanesulfonate, 6-10 parts of anhydrous sodium carbonate, and 40-60 parts of water are mixed, and stirred at a temperature of 90-100° C. for 2-4 hours to obtain sodium dihydroxypropanesulfonate amine.

9. The method for preparing a polymerization inhibitor used in a butadiene refining process according to claim 3, characterized in that: In step S4, the reaction is stirred at a temperature of 45-65° C. and a rate of 450-550 r / min for 30-50 min.

10. The method for preparing a polymerization inhibitor used in a butadiene refining process according to claim 3, characterized in that: In step S5, the reaction is stirred at a temperature of 70-90° C. and a rate of 500-600 r / min for 1.5-3.5 h.

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