Composite stabilizer for 2-bromo-3, 3, 3-trifluoropropene and use method thereof

Abstract

The invention relates to a compound stabilizer of 2-bromo-3, 3, 3-trifluoropropene and a use method thereof, the compound stabilizer comprises a phenolic compound, a phosphite ester or thioester compound and an acid binding agent, the molar ratio of the phenolic compound, the phosphite ester or thioester compound and the acid binding agent is 1: (0.1-6): (0.1-6), and the mass ratio of the phenolic compound, the phosphite ester or thioester compound and the acid binding agent to the 2-bromo-3, 3, 3-trifluoropropene is (0.001-1.0): 100. Through the interaction of the components of the stabilizers and the rectification treatment process of the product, the deterioration problems of value increase, color yellowing, purity reduction and the like of the 2-bromo-3, 3, 3-trifluoroacrylic acid can be effectively inhibited, excellent long-acting stability is provided, the production, transportation and storage of the 2-bromo-3, 3, 3-trifluoroacrylic acid are facilitated, and the product has good market prospects. The smooth application in the fields of novel fire extinguishing agents, organic synthesis and the like is ensured.

Description

Technical Field

[0001] The invention relates to the technical field of chemical additives, and in particular to a composite stabilizer for improving the stability of 2-bromo-3,3,3-trifluoropropene and a use method thereof. Background Art

[0002] 2-Bromo-3,3,3-trifluoropropene is an important organic compound, which is widely used in refrigerants, high-efficiency fire extinguishing agents and organic synthesis. The molecular structure of 2-Bromo-3,3,3-trifluoropropene contains bromine atoms and unsaturated double bonds, and has a low boiling point. In the field of fire extinguishing agents, it has outstanding advantages such as high fire extinguishing efficiency, clean and residue-free, low atmospheric greenhouse effect value and ozone depletion value, and environmental friendliness. It is an ideal substitute for traditional halon fire extinguishing agents and perfluoroalkane fire extinguishing agents, and has broad market application prospects.

[0003] Due to the presence of bromine atoms, 2-bromo-3,3,3-trifluoropropene is very prone to free radical chain reactions, resulting in deterioration phenomena such as increased acid value, yellowing, and reduced purity, especially at high temperatures, and even during the production distillation process. The highly perishable nature of 2-bromo-3,3,3-trifluoropropene has brought great inconvenience to production, transportation, and storage, and has seriously affected the quality and performance of the product, limiting its application in the field of fire extinguishing agents.

[0004] At present, there are relevant literatures introducing the synthesis method of 2-bromo-3,3,3-trifluoropropene and its application in new fire extinguishing agents. For example, CN102206134A, CN103232319A, CN113087589A and other patents disclose some synthesis methods of 2-bromo-3,3,3-trifluoropropene; CN115888002A discloses a new clean and efficient gas fire extinguishing agent with perfluorohexanone and 2-bromo-3,3,3-trifluoropropene as main components; "Fire Science and Technology", 41(7), 873-876(2022) studied 2-bromo-3,3,3-trifluoropropene. The fire extinguishing and cooling effect of 2-bromo-3,3,3-trifluoropropene on battery fires; the ratio of the composite fire extinguishing medium formed by 2-bromo-3,3,3-trifluoropropene and nitrogen and the critical fire extinguishing conditions under different ratios were studied in "Fire Science", 19(2), 60-67(2010); the generation mechanism and amount of hydrogen fluoride during the fire extinguishing process of 2-bromo-3,3,3-trifluoropropene were studied in "Acta Chimica Sinica", 68(18), 1829-1836(2010). However, none of the above literatures mentioned the deterioration problems of 2-bromo-3,3,3-trifluoropropene, such as the increase of acid value, yellowing of color, and reduction of purity, during the synthesis, storage and application of 2-bromo-3,3,3-trifluoropropene. Summary of the invention

[0005] In view of the above-mentioned prior art conditions, the present invention provides a composite stabilizer for 2-bromo-3,3,3-trifluoropropene and a method for using the same. The composite stabilizer can effectively inhibit the decomposition of 2-bromo-3,3,3-trifluoropropene and solve the problem that 2-bromo-3,3,3-trifluoropropene is easily deteriorated during production, transportation, storage and application.

[0006] The technical solution of the present invention can be summarized as follows:

[0007] The composite stabilizer of 2-bromo-3,3,3-trifluoropropene includes: a phenolic compound, a phosphite or thioester compound, and an acid binding agent.

[0008] According to the present invention, preferably, the molar ratio of the phenolic compound, the phosphite or thioester compound, and the acid-binding agent is 1:(0.1-6):(0.1-6).

[0009] According to the present invention, preferably, the phenolic compound is a monophenol, diphenol, polyphenol or hindered phenol or semi-hindered phenol antioxidant containing one or more aliphatic substituents;

[0010] More preferably, it is one or a combination of p-hydroxyanisole, hydroquinone, 2-methylhydroquinone, 2-tert-butylhydroquinone, p-tert-butylcatechol, 2,6-di-tert-butyl-p-cresol, 2,6-di-tert-butyl-p-ethylphenol, 2,4-dimethyl-6-tert-butylphenol, pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, triethylene glycol bis[β-(3-tert-butyl-4-hydroxy-5-methylphenyl)propionate], and 2,2'-methylenebis(4-methyl-6-tert-butylphenol);

[0011] More preferably, the phenolic compound is one or a combination of p-hydroxyanisole, 2-tert-butylhydroquinone, 2,6-di-tert-butyl-p-cresol, pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, etc.

[0012] According to the present invention, preferably, the phosphite compound is an aliphatic or aromatic phosphite triester compound or a phosphite antioxidant;

[0013] More preferably, it is one or a combination of triethyl phosphite, tributyl phosphite, trioctyl phosphite, triphenyl phosphite, trisphenol A phosphite, tris[2,4-di-tert-butylphenyl]phosphite, bis(2,4-di-tert-butylphenol)pentaerythritol diphosphite, and bis(2,4-dicumylphenyl)pentaerythritol diphosphite;

[0014] More preferably, the phosphite compound is one or a combination of triethyl phosphite, tributyl phosphite, tri[2,4-di-tert-butylphenyl]phosphite, etc.

[0015] According to the present invention, preferably, the thioester compound is a thioester antioxidant; more preferably, it is one or a combination of two or more of dilauryl thiodipropionate, dioctadecyl thiodipropionate, and pentaerythritol tetrakis (3-lauryl thiopropionate);

[0016] More preferably, the thioester compound is one or a combination of two or more of dilauryl thiodipropionate and dioctadecyl thiodipropionate.

[0017] According to the present invention, preferably, the acid-binding agent is an aromatic, aliphatic, alicyclic or alkenyl epoxy compound, and more preferably is phenyl glycidyl ether, n-butyl glycidyl ether, isobutyl glycidyl ether, ethylene glycol diglycidyl ether, butanediol diglycidyl ether, hexanediol diglycidyl ether, glycerol triglycidyl ether, allyl glycidyl ether, glycidyl acrylate, glycidyl methacrylate, bis[(3,4-epoxycyclohexyl)methyl]adipate or a combination of several thereof;

[0018] More preferably, the acid binding agent is one or a combination of glycerol triglycidyl ether, hexanediol diglycidyl ether, and glycidyl methacrylate.

[0019] According to the present invention, preferably, the molar ratio of the phenolic compound, the phosphite or thioester compound, and the acid-binding agent is 1:(1-3):(1-5).

[0020] According to the present invention, preferably, the composite stabilizer of 2-bromo-3,3,3-trifluoropropene comprises the following components in molar parts:

[0021] 1 part of p-hydroxyanisole, 0.4-0.8 parts of tributyl phosphite, and 0.8-1.2 parts of allyl glycidyl ether.

[0022] According to the present invention, preferably, the composite stabilizer of 2-bromo-3,3,3-trifluoropropene comprises the following components in molar parts:

[0023] 1 part of pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, 2-3 parts of tris[2,4-di-tert-butylphenyl]phosphite, 4-6 parts of hexanediol diglycidyl ether.

[0024] According to the present invention, preferably, the composite stabilizer of 2-bromo-3,3,3-trifluoropropene comprises the following components in molar parts:

[0025] 1 part of pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, 1-3 parts of distearyl thiodipropionate, and 4-6 parts of hexanediol diglycidyl ether.

[0026] According to the present invention, the method for using the composite stabilizer of 2-bromo-3,3,3-trifluoropropene comprises the following steps:

[0027] The composite stabilizer is added to the product of 2-bromo-3,3,3-trifluoropropene, and the mass ratio of the composite stabilizer to 2-bromo-3,3,3-trifluoropropene is 0.001 to 1.0:100, preferably 0.005 to 0.5:100.

[0028] According to the present invention, preferably, the composite stabilizer is added to the crude product of 2-bromo-3,3,3-trifluoropropene, and then further distilled;

[0029] Preferably, an alkali solution with a mass concentration of 3 to 30% is added to the crude product of 2-bromo-3,3,3-trifluoropropene or the 2-bromo-3,3,3-trifluoropropene product with a high acid value, the mass ratio of the alkali solution to the 2-bromo-3,3,3-trifluoropropene is 0.1 to 3:10, the alkali solution floats on the liquid surface of the 2-bromo-3,3,3-trifluoropropene, and then the distillation is started;

[0030] Preferably, the alkali solution is a sodium hydroxide solution, the mass concentration of the sodium hydroxide solution is 5-10%, and the mass ratio of the alkali solution to 2-bromo-3,3,3-trifluoropropene is 0.5-1.5:10.

[0031] According to the present invention, a distillation method for 2-bromo-3,3,3-trifluoropropene is also provided, comprising the following steps:

[0032] Adding alkali solution with a mass concentration of 3 to 30% to the crude product of 2-bromo-3,3,3-trifluoropropene or the 2-bromo-3,3,3-trifluoropropene product with a high acid value, wherein the mass ratio of the alkali solution to the 2-bromo-3,3,3-trifluoropropene is 0.1 to 3:10, and the alkali solution floats on the liquid surface of the 2-bromo-3,3,3-trifluoropropene, and then starting distillation;

[0033] Preferably, the alkali solution is a sodium hydroxide solution, the concentration of the sodium hydroxide solution is 5-10%, and the mass ratio of the alkali solution to 2-bromo-3,3,3-trifluoropropene is 0.5-1.5:10.

[0034] According to the present invention, preferably, the composite stabilizer is dissolved in the crude 2-bromo-3,3,3-trifluoropropene product for distillation, and the mass concentration of the composite stabilizer in the crude 2-bromo-3,3,3-trifluoropropene product is 1-20%. During the distillation process, preferably, a metering pump is used to continuously pump the composite stabilizer solution into the 2-bromo-3,3,3-trifluoropropene product fraction through the production pipeline, so that the 2-bromo-3,3,3-trifluoropropene product can contact the composite stabilizer in a timely and sufficient manner; further preferably, the concentration of the composite stabilizer solution is 5-10%;

[0035] Preferably, the composite stabilizer is added by directly pumping a sufficient amount through a metering pump during distillation, or by first pumping a small amount and then adding it to the 2-bromo-3,3,3-trifluoropropene product fraction.

[0036] Beneficial effects of the present invention:

[0037] 1. The present invention provides a composite stabilizer composition for 2-bromo-3,3,3-trifluoropropene and a method for using the same, wherein a combination of a phenolic compound, a phosphite or thioester compound, and an acid-binding agent is selected as the composite stabilizer. The components of the composite stabilizer work together to significantly improve the stability of 2-bromo-3,3,3-trifluoropropene during production, storage, transportation, and application. When used in conjunction with a distillation treatment method, the effect is even better.

[0038] 2. Experimental results show that the 2-bromo-3,3,3-trifluoropropene product prepared by using the composite stabilizer of the present invention has excellent stability and can remain unchanged for at least 5 years under normal storage conditions. DETAILED DESCRIPTION

[0039] The invention provides a composite stabilizer for 2-bromo-3,3,3-trifluoropropene and a use method thereof. The composite stabilizer can effectively inhibit the decomposition of 2-bromo-3,3,3-trifluoropropene, and solves the problem that 2-bromo-3,3,3-trifluoropropene is easily deteriorated during production, transportation, storage and application.

[0040] The composite stabilizer of 2-bromo-3,3,3-trifluoropropene includes: a phenolic compound, a phosphite or thioester compound, and an acid binding agent.

[0041] In one or more preferred embodiments, the molar ratio of the phenolic compound, the phosphite or thioester compound, and the acid-binding agent is 1:(0.1-6):(0.1-6).

[0042] According to the present invention, the three components of the composite stabilizer have obvious synergistic effects. The role of the phenolic substance is to absorb the free radicals generated by the deterioration of 2-bromo-3,3,3-trifluoropropene and prevent the chain reaction;

[0043] In one or more preferred embodiments, the phenolic compound is a monophenol, diphenol, polyphenol, or hindered phenol or semi-hindered phenol antioxidant containing one or more aliphatic substituents;

[0044] Preferably, it is one or a combination of p-hydroxyanisole, hydroquinone, 2-methylhydroquinone, 2-tert-butylhydroquinone, p-tert-butylcatechol, 2,6-di-tert-butyl-p-cresol, 2,6-di-tert-butyl-p-ethylphenol, 2,4-dimethyl-6-tert-butylphenol, pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, triethylene glycol bis[β-(3-tert-butyl-4-hydroxy-5-methylphenyl)propionate], and 2,2'-methylenebis(4-methyl-6-tert-butylphenol);

[0045] More preferably, the phenolic compound is one or a combination of p-hydroxyanisole, 2-tert-butylhydroquinone, 2,6-di-tert-butyl-p-cresol, pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, etc.

[0046] According to the present invention, the role of the phosphite or thioester compound is to solve the color stain of the phenolic compound and improve the color change problem of the sample during storage;

[0047] In one or more preferred embodiments, the phosphite compound is an aliphatic or aromatic phosphite triester compound or a phosphite antioxidant;

[0048] Preferably, one or a combination of triethyl phosphite, tributyl phosphite, trioctyl phosphite, triphenyl phosphite, trisphenol A phosphite, tris[2,4-di-tert-butylphenyl]phosphite, bis(2,4-di-tert-butylphenol)pentaerythritol diphosphite, and bis(2,4-dicumylphenyl)pentaerythritol diphosphite;

[0049] More preferably, the phosphite compound is one or a combination of triethyl phosphite, tributyl phosphite, tri[2,4-di-tert-butylphenyl]phosphite, etc.

[0050] In one or more preferred embodiments, the thioester compound is a thioester antioxidant; more preferably, it is one or a combination of disodium thiodipropionate, distearyl thiodipropionate, and pentaerythritol tetrakis (3-lauryl thiopropionate);

[0051] More preferably, the thioester compound is one or a combination of two or more of dilauryl thiodipropionate and dioctadecyl thiodipropionate.

[0052] According to the present invention, the acid-binding agent has the function of absorbing the acidic substances produced in the deterioration process, controlling the acid value of the product to be lower, and also has the function of controlling the color of the product.

[0053] In one or more preferred embodiments, the acid-binding agent is an aromatic, aliphatic, alicyclic or alkenyl epoxy compound, preferably phenyl glycidyl ether, n-butyl glycidyl ether, isobutyl glycidyl ether, ethylene glycol diglycidyl ether, butanediol diglycidyl ether, hexanediol diglycidyl ether, glycerol triglycidyl ether, allyl glycidyl ether, glycidyl acrylate, glycidyl methacrylate, bis[(3,4-epoxycyclohexyl)methyl]adipate or a combination of the above;

[0054] More preferably, the acid binding agent is one or a combination of glycerol triglycidyl ether, hexanediol diglycidyl ether, and glycidyl methacrylate.

[0055] In one or more preferred embodiments, the molar ratio of the phenolic compound, the phosphite or thioester compound, and the acid-binding agent is 1:(1-3):(1-5).

[0056] In one or more preferred embodiments, the composite stabilizer of 2-bromo-3,3,3-trifluoropropene comprises the following components in molar proportions:

[0057] 1 part of p-hydroxyanisole, 0.4-0.8 parts of tributyl phosphite, and 0.8-1.2 parts of allyl glycidyl ether.

[0058] In one or more preferred embodiments, the composite stabilizer of 2-bromo-3,3,3-trifluoropropene comprises the following components in molar proportions:

[0059] 1 part of pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, 2-3 parts of tris[2,4-di-tert-butylphenyl]phosphite, 4-6 parts of hexanediol diglycidyl ether.

[0060] In one or more preferred embodiments, the composite stabilizer of 2-bromo-3,3,3-trifluoropropene comprises the following components in molar proportions:

[0061] 1 part of pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, 1-3 parts of distearyl thiodipropionate, and 4-6 parts of hexanediol diglycidyl ether.

[0062] According to the present invention, the method for using the composite stabilizer of 2-bromo-3,3,3-trifluoropropene comprises the following steps:

[0063] The composite stabilizer is added to the product of 2-bromo-3,3,3-trifluoropropene, and the mass ratio of the composite stabilizer to 2-bromo-3,3,3-trifluoropropene is 0.001 to 1.0:100, preferably 0.005 to 0.5:100.

[0064] In one or more preferred embodiments, the composite stabilizer is added to the crude product of 2-bromo-3,3,3-trifluoropropene, and then further distilled;

[0065] Preferably, an alkali solution with a mass concentration of 3 to 30% is added to the crude product of 2-bromo-3,3,3-trifluoropropene or the 2-bromo-3,3,3-trifluoropropene product with a high acid value, the mass ratio of the alkali solution to the 2-bromo-3,3,3-trifluoropropene is 0.1 to 3:10, the alkali solution floats on the liquid surface of the 2-bromo-3,3,3-trifluoropropene, and then the distillation is started;

[0066] Preferably, the alkali solution is a sodium hydroxide solution, the mass concentration of the sodium hydroxide solution is 5-10%, and the mass ratio of the alkali solution to 2-bromo-3,3,3-trifluoropropene is 0.5-1.5:10.

[0067] According to the present invention, a distillation treatment method for 2-bromo-3,3,3-trifluoropropene is also provided, the purpose of which is to obtain a product with a low initial acid value so as to cooperate with the above-mentioned composite stabilizer to exert the best effect.

[0068] The distillation treatment method of 2-bromo-3,3,3-trifluoropropene comprises the following steps:

[0069] Alkali solution with a mass concentration of 3 to 30% is added to the crude product of 2-bromo-3,3,3-trifluoropropene or the 2-bromo-3,3,3-trifluoropropene product with a higher acid value, the mass ratio of the alkali solution to 2-bromo-3,3,3-trifluoropropene is 0.1 to 3:10, the alkali solution floats on the liquid surface of 2-bromo-3,3,3-trifluoropropene, and then distillation is started.

[0070] In one or more preferred embodiments, the alkali solution is a sodium hydroxide solution, the concentration of the sodium hydroxide solution is 5-10%, and the mass ratio of the alkali solution to 2-bromo-3,3,3-trifluoropropene is 0.5-1.5:10.

[0071] In one or more preferred embodiments, the composite stabilizer is dissolved in the crude 2-bromo-3,3,3-trifluoropropene product for distillation, and the mass concentration of the composite stabilizer in the crude 2-bromo-3,3,3-trifluoropropene product is 1-20%. During the distillation process, a metering pump is preferably used to continuously pump the composite stabilizer solution into the 2-bromo-3,3,3-trifluoropropene product fraction through the production pipeline, so that the 2-bromo-3,3,3-trifluoropropene product can be timely and fully contacted with the composite stabilizer; further preferably, the concentration of the composite stabilizer solution is 5-10%;

[0072] Preferably, the composite stabilizer is added by directly pumping a sufficient amount through a metering pump during distillation, or by first pumping a small amount and then adding it to the 2-bromo-3,3,3-trifluoropropene product fraction.

[0073] In order to enable those skilled in the art to better understand the technical solution of the present invention, the composite stabilizer composition and the use method thereof provided by the present invention are described in detail below in conjunction with specific embodiments, and the protection scope of the present invention is not limited by the following embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without creative work belong to the protection scope of the present invention.

[0074] In the examples, all the raw materials used are conventional commercially available products.

[0075] Example 1

[0076] 10 kg of crude 2-bromo-3,3,3-trifluoropropene and 1 kg of 5% sodium hydroxide solution are added to a 10 L distillation experimental kettle; 3 g of p-hydroxyanisole, 3 g of tributyl phosphite and 3 g of allyl glycidyl ether are added to 200 g of qualified 2-bromo-3,3,3-trifluoropropene product, and stirred to fully dissolve to obtain a composite stabilizer solution; heating is turned on to start distillation, and the purity of the fraction is monitored by gas chromatography. When the purity of the fraction is qualified, the product is started to be produced, and at the same time, the prepared composite stabilizer solution is uniformly metered and pumped into the production pipeline through a horizontal flow pump; the qualified product produced by distillation is dehydrated by a molecular sieve to obtain a dry 2-bromo-3,3,3-trifluoropropene product with the composite stabilizer added; the 2-bromo-3,3,3-trifluoropropene product is sealed and stored at room temperature and away from light.

[0077] Example 2

[0078] Add 10 kg of crude 2-bromo-3,3,3-trifluoropropene and 2 kg of 10% sodium hydroxide solution to a 10 L distillation reactor; add 0.5 g of pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, 0.5 g of tris[2,4-di-tert-butylphenyl]phosphite and 0.5 g of hexanediol diglycidyl ether to 200 g of qualified The 2-bromo-3,3,3-trifluoropropene product is stirred and fully dissolved to obtain a composite stabilizer solution; heating is turned on to start distillation, and the purity of the fraction is monitored by gas chromatography. When the purity of the fraction is qualified, the product is started to be produced, and at the same time, the prepared composite stabilizer solution is uniformly metered and pumped into the production pipeline by a horizontal flow pump; the qualified product produced by distillation is dehydrated by a molecular sieve to obtain a dry 2-bromo-3,3,3-trifluoropropene product with the composite stabilizer added; the 2-bromo-3,3,3-trifluoropropene product is sealed and stored at room temperature and away from light.

[0079] Example 3

[0080] The method is basically the same as Example 2, except that the ratio of the composite stabilizer solution is 200 g of 2-bromo-3,3,3-trifluoropropene product dissolving 0.5 g of pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, 0.5 g of disodium thiodipropionate and 0.5 g of hexanediol diglycidyl ether.

[0081] Comparative Example 1

[0082] Add 10Kg of crude 2-bromo-3,3,3-trifluoropropene and 1Kg of 5% sodium hydroxide solution into a 10L distillation experimental kettle; turn on the heating to start distillation, monitor the purity of the fraction by gas chromatography, and start to produce products when the purity of the fraction is qualified; the qualified products produced by distillation are dehydrated by molecular sieves, sealed, and stored at room temperature and away from light.

[0083] Comparative Example 2

[0084] The method is basically the same as Example 2, except that: the ratio of the composite stabilizer solution is 200 g of 2-bromo-3,3,3-trifluoropropene product dissolved with 1 g of pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate and 0.5 g of distearyl thiodipropionate.

[0085] Comparative Example 3

[0086] The method is basically the same as Example 2, except that the ratio of the composite stabilizer solution is 200 g of 2-bromo-3,3,3-trifluoropropene product dissolved with 1 g of pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate and 0.5 g of hexanediol diglycidyl ether.

[0087] Comparative Example 4

[0088] The method is basically the same as Example 2, except that the distillation treatment capacity is large, the time required for distillation is long, and there is no coordinated distillation treatment process. 3500Kg of 2-bromo-3,3,3-trifluoropropene crude product is added to a 2500L distillation kettle, heating is turned on to start distillation, and the fraction purity is monitored by gas chromatography. When the fraction purity is qualified, the product is extracted, and the qualified product extracted by distillation is dehydrated by molecular sieve; 175g of tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionic acid] pentaerythritol ester, 175g of tris[2,4-di-tert-butylphenyl] phosphite and 175g of hexanediol diglycidyl ether are added by metering, stirred and fully dissolved, and a dry 2-bromo-3,3,3-trifluoropropene product with a composite stabilizer added is obtained; this 2-bromo-3,3,3-trifluoropropene product is sealed and stored at room temperature and away from light.

[0089] Test Example 1

[0090] The color of each sample was observed, and the purity and acid value of each sample were tested according to ASTM D8060-16 standard. The results are listed in Table 1.

[0091] Table 1 Appearance and test results of each sample

[0092]

[0093]

[0094] It can be seen from the test data in Table 1 that the samples with the addition of phenolic compounds, phosphites or thioester compounds, and an acid-binding agent composite stabilizer have the best stability; the sample in Comparative Example 1 does not add any stabilizer, and obvious deterioration occurs, the color turns yellow, the purity decreases, the acid value increases significantly, and there is a pungent smell; the sample in Comparative Example 2 uses a combination stabilizer of phenolic compounds and thioester compounds, which has a certain stabilizing effect, but the increase in acid value is difficult to control, and the high acid value further promotes the deterioration and yellowing of the sample; the sample in Comparative Example 3 uses a combination stabilizer of phenolic compounds and an acid-binding agent, which can better exert stability, and the acid value and purity are effectively controlled, but the appearance color of the sample will be significantly deepened; Comparative Example 4 adds a three-component composite stabilizer, but does not adopt a distillation treatment process, especially under high temperature conditions, it is easy to cause the initial acid value of the sample to be high, and the sample will gradually change color, affecting the use effect of the composite stabilizer.

[0095] In summary, there is an obvious synergistic effect between the three components of the composite stabilizer: the role of phenolic substances is to absorb the free radicals generated by the deterioration of 2-bromo-3,3,3-trifluoropropene and prevent chain reactions; the role of phosphites or thioester compounds is to solve the color pollution of phenolic compounds and improve the discoloration problem of samples during storage; and the role of acid binding agents is to absorb acidic substances generated during the deterioration process, control the lower acid value of the product, and also control the color of the product; the above three cooperate with each other and are indispensable. In addition, since 2-bromo-3,3,3-trifluoropropene is very easy to deteriorate, especially in the high temperature environment in summer, it is also very necessary to use it in conjunction with the distillation treatment process, which helps to eliminate the interference of acid value, ensure the use effect of the composite stabilizer, and exert long-term stability.

[0096] Test Example 2

[0097] For the samples of Example 2 and Example 3, a long-term stability test was conducted, the color of the samples was observed regularly, and the purity and acid value of the samples were tested according to the ASTM D8060-16 standard. The results are listed in Table 2.

[0098] Table 2 Statistics of long-term stability test results

[0099]

[0100]

[0101] It can be seen from the test results in Table 2 that, for the samples of Example 2 and Example 3, after being stored at room temperature and away from light for 5 years, the color, purity and acid value did not change significantly, and the long-term stability was excellent.

[0102] The above is a preferred embodiment of the present invention and does not limit the patent scope of the present invention. For those skilled in the art, the technical solutions of the above embodiments can be modified, or some of the technical features can be replaced by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention and directly or indirectly applied to other related technical fields shall be included in the protection scope of the present invention.

Claims

1. A composite stabilizer of 2-bromo-3,3,3-trifluoropropene, characterized in that: The composite stabilizer comprises the following components: a phenolic compound, a phosphite or thioester compound, and an acid binding agent.

2. The composite stabilizer of 2-bromo-3,3,3-trifluoropropene according to claim 1, characterized in that: The molar ratio of the phenolic compound, the phosphite or thioester compound and the acid-binding agent is 1:(0.1-6):(0.1-6).

3. The composite stabilizer of 2-bromo-3,3,3-trifluoropropene according to claim 1, characterized in that: The phenolic compound is a monophenol, diphenol, polyphenol, hindered phenol, or semi-hindered phenol antioxidant containing one or more aliphatic substituents; preferably, it is one or a combination of p-hydroxyanisole, hydroquinone, 2-methylhydroquinone, 2-tert-butylhydroquinone, p-tert-butylcatechol, 2,6-di-tert-butyl-p-cresol, 2,6-di-tert-butyl-p-ethylphenol, 2,4-dimethyl-6-tert-butylphenol, pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, triethylene glycol bis[β-(3-tert-butyl-4-hydroxy-5-methylphenyl)propionate], and 2,2'-methylenebis(4-methyl-6-tert-butylphenol); Preferably, the phosphite compound is an aliphatic or aromatic triester phosphite compound or a phosphite antioxidant; preferably, it is one or a combination of triethyl phosphite, tributyl phosphite, trioctyl phosphite, triphenyl phosphite, tribisphenol A phosphite, tris[2,4-di-tert-butylphenyl]phosphite, bis(2,4-di-tert-butylphenol)pentaerythritol diphosphite, and bis(2,4-dicumylphenyl)pentaerythritol diphosphite; Preferably, the thioester compound is a thioester antioxidant; more preferably, it is one or a combination of two or more of dilauryl thiodipropionate, dioctadecyl thiodipropionate, and pentaerythritol tetrakis (3-lauryl thiopropionate); Preferably, the acid binding agent is an aromatic, aliphatic, alicyclic or alkenyl epoxy compound, and is further preferably one or a combination of phenyl glycidyl ether, n-butyl glycidyl ether, isobutyl glycidyl ether, ethylene glycol diglycidyl ether, butanediol diglycidyl ether, hexanediol diglycidyl ether, glycerol triglycidyl ether, allyl glycidyl ether, glycidyl acrylate, glycidyl methacrylate, and bis[(3,4-epoxycyclohexyl)methyl]adipate.

4. The composite stabilizer of 2-bromo-3,3,3-trifluoropropene according to claim 1, characterized in that: The molar ratio of the phenolic compound, the phosphite or thioester compound and the acid-binding agent is 1:(1-3):(1-5).

5. The composite stabilizer of 2-bromo-3,3,3-trifluoropropene according to claim 1, characterized in that: The composite stabilizer of 2-bromo-3,3,3-trifluoropropene comprises the following components in molar parts: 1 part of p-hydroxyanisole, 0.4-0.8 parts of tributyl phosphite, and 0.8-1.2 parts of allyl glycidyl ether.

6. The composite stabilizer of 2-bromo-3,3,3-trifluoropropene according to claim 1, characterized in that: The composite stabilizer of 2-bromo-3,3,3-trifluoropropene comprises the following components in molar parts: 1 part of pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, 2-3 parts of tris[2,4-di-tert-butylphenyl]phosphite, 4-6 parts of hexanediol diglycidyl ether.

7. The composite stabilizer of 2-bromo-3,3,3-trifluoropropene according to claim 1, characterized in that: The composite stabilizer of 2-bromo-3,3,3-trifluoropropene comprises the following components in molar parts: 1 part of pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, 1-3 parts of distearyl thiodipropionate, and 4-6 parts of hexanediol diglycidyl ether.

8. A method for using the composite stabilizer of 2-bromo-3,3,3-trifluoropropene according to any one of claims 1 to 7, comprising the following steps: The composite stabilizer is added into the product of 2-bromo-3,3,3-trifluoropropene, and the mass ratio of the composite stabilizer to 2-bromo-3,3,3-trifluoropropene is 0.001-1.0:

100.

9. The method for using the composite stabilizer of 2-bromo-3,3,3-trifluoropropene according to claim 8, characterized in that: adding the composite stabilizer to the crude product of 2-bromo-3,3,3-trifluoropropene, and further rectifying the product; Preferably, an alkali solution with a mass concentration of 3 to 30% is added to the crude product of 2-bromo-3,3,3-trifluoropropene or the 2-bromo-3,3,3-trifluoropropene product with a high acid value, the mass ratio of the alkali solution to the 2-bromo-3,3,3-trifluoropropene is 0.1 to 3:10, the alkali solution floats on the liquid surface of the 2-bromo-3,3,3-trifluoropropene, and then the distillation is started; Preferably, the alkali solution is a sodium hydroxide solution, the mass concentration of the sodium hydroxide solution is 5-10%, and the mass ratio of the alkali solution to 2-bromo-3,3,3-trifluoropropene is 0.5-1.5:

10.

10. A distillation treatment method for 2-bromo-3,3,3-trifluoropropene, comprising using the composite stabilizer of 2-bromo-3,3,3-trifluoropropene according to any one of claims 1 to 7, comprising the following steps: Adding alkali solution with a mass concentration of 3 to 30% to a crude product of 2-bromo-3,3,3-trifluoropropene or a 2-bromo-3,3,3-trifluoropropene product with a higher acid value, wherein the mass ratio of the alkali solution to the 2-bromo-3,3,3-trifluoropropene is 0.1 to 3:10, and the alkali solution floats on the liquid surface of the 2-bromo-3,3,3-trifluoropropene, and then starting distillation; preferably, the alkali solution is a sodium hydroxide solution, wherein the concentration of the sodium hydroxide solution is 5 to 10%, and the mass ratio of the alkali solution to the 2-bromo-3,3,3-trifluoropropene is 0.5 to 1.5:10; The composite stabilizer is dissolved in a crude 2-bromo-3,3,3-trifluoropropene product and distilled. The mass concentration of the composite stabilizer in the crude 2-bromo-3,3,3-trifluoropropene product is 1-20%. During the distillation process, a metering pump is preferably used to continuously pump the composite stabilizer solution into the 2-bromo-3,3,3-trifluoropropene product fraction through a production pipeline, so that the 2-bromo-3,3,3-trifluoropropene product can be timely and fully contacted with the composite stabilizer; Preferably, the composite stabilizer is added by directly pumping a sufficient amount through a metering pump during distillation, or by first pumping a small amount and then adding it to the 2-bromo-3,3,3-trifluoropropene product fraction.

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