Tert-butylhydroquinone and purification method thereof

Abstract

The purification method comprises the following steps that A, organic acid is evenly dissolved in deionized water, and an acidity stabilizer is prepared; b, adding the tert-butylhydroquinone crude product and a reducing agent into an acidity stabilizer, and heating and dissolving to obtain a crude product solution; c, standing and layering the crude product solution to obtain an upper-layer solution, transferring the upper-layer solution into a crystallization kettle, introducing inert gas into the crystallization kettle, cooling and crystallizing, and centrifuging to obtain a semi-refined tert-butylhydroquinone product; d, uniformly dissolving organic acid in an ethanol solution to prepare an organic acid ethanol solution; e, adding the semi-refined tert-butylhydroquinone into the organic acid ethanol solution, and heating and dissolving to obtain a refined solution; and F, sequentially carrying out decoloration, cooling crystallization, centrifugation, drying and crushing on the refined solution to obtain the tert-butylhydroquinone. According to the scheme, the whiteness and the shelf life of the tert-butylhydroquinone are improved, so that the defects in the prior art are overcome.

Description

Technical Field

[0001] The invention relates to the technical field of tert-butylhydroquinone purification, in particular to tert-butylhydroquinone and a purification method thereof. Background Art

[0002] Tert-butylhydroquinone (TBHQ) is a new type of food antioxidant with low toxicity and high efficiency, which has a wide range of applications. It is used in rubber, plastic, cosmetics and other industries. TBHQ is an important use as an antioxidant for edible oils and fats, which has the advantages of high efficiency and low toxicity.

[0003] TBHQ is a product obtained by alkylation reaction between hydroquinone and an alkylating agent. The production method of TBHQ has only appeared more frequently in literature reports from various countries in the past two decades. Chinese scientists began to study its production method in the mid-to-late 1990s. At present, the basic synthetic route of all reported TBHQ production processes is to use hydroquinone as the parent, and to prepare it with isobutylene or tert-butyl alcohol as the alkylating agent under strong acid catalysis.

[0004] The tert-butylhydroquinone product prepared by the existing purification method has poor stability, with a whiteness of about 78 to 85 degrees and a shelf life of only about 3 to 6 months. Therefore, it needs to be used immediately after preparation and is difficult to store for a long time. Summary of the invention

[0005] The purpose of the present invention is to provide a tert-butylhydroquinone and a purification method thereof, which are beneficial to improving the whiteness and shelf life of tert-butylhydroquinone, so as to overcome the shortcomings of the prior art.

[0006] To achieve this object, the present invention adopts the following technical solutions:

[0007] A method for purifying tert-butylhydroquinone comprises the following steps:

[0008] A. Evenly dissolving an organic acid in deionized water to prepare an acidity stabilizer;

[0009] B. adding crude tert-butylhydroquinone and a reducing agent to the acidity stabilizer, and heating to dissolve to obtain a crude product solution;

[0010] C. The upper layer solution obtained after the crude product solution is allowed to stand for stratification is transferred into a crystallization kettle, and an inert gas is introduced into the interior of the crystallization kettle. After cooling and crystallization, centrifugation is performed to obtain a semi-fine product of tert-butylhydroquinone;

[0011] D. uniformly dissolving the organic acid in the ethanol solution to prepare an organic acid ethanol solution;

[0012] E. adding the semi-fine tert-butylhydroquinone to the organic acid ethanol solution, heating and dissolving to obtain a fine solution;

[0013] F. Decolorizing, cooling, crystallizing, centrifuging, drying and crushing the fine product solution in sequence to obtain tert-butylhydroquinone.

[0014] Preferably, in step A, the ratio of the organic acid to the deionized water is 1:(200-1000) by mass.

[0015] In step B, the addition ratio of the crude tert-butylhydroquinone, the reducing agent and the acidity stabilizer is 1: (0.01-0.015): (10-20) according to the mass ratio.

[0016] Preferably, in step B, the heating temperature for heating and dissolving is 95-100° C.;

[0017] In step C, the cooling temperature of the cooling crystallization is 20-50° C., and the inert gas is nitrogen; in terms of mass percentage, the oxygen content of the crystallization kettle is less than 3%.

[0018] Preferably, in step A, the organic acid is any one of citric acid, oxalic acid and malic acid;

[0019] In step B, the reducing agent is any one of sodium sulfite, sodium dithionite and sodium pyrosulfite.

[0020] Preferably, in step F, the specific step of decolorization is: adding activated carbon to the fine solution at 70-75° C., decolorizing for 0.5 h and then filtering.

[0021] Preferably, in step F, the specific step of drying is: putting the powder obtained after centrifugation into an oven for drying, the drying time is 8 to 12 hours, and the oven is ventilated in the first 0.5 to 1 hour of the drying process.

[0022] Preferably, in step D, the raw materials of the organic acid ethanol solution include organic acid, ethanol and water, and the preparation ratio of the organic acid, the ethanol and the water is (0.2-1): (15-50): (49-84.8) in terms of mass ratio;

[0023] In step E, the addition ratio of the tert-butylhydroquinone semi-fine product and the organic acid ethanol solution is 1:(2.5-5) in terms of mass ratio.

[0024] Preferably, in step E, the heating temperature for heating and dissolving is 70-75°C;

[0025] In step F, the cooling temperature of the cooling crystallization is 25-30° C.; the specific steps of the centrifugation are: placing the precipitated phase after the cooling crystallization in a centrifuge, performing centrifugal washing and spinning, discarding the liquid phase after the centrifugal spinning, and taking out the solid phase to form a powder.

[0026] Preferably, in step D, the organic acid is any one of citric acid, oxalic acid and malic acid.

[0027] A tert-butylhydroquinone is prepared by using the above-mentioned method for purifying tert-butylhydroquinone, and according to mass percentage, the purity of the tert-butylhydroquinone reaches at least 99.6%, and the whiteness of the tert-butylhydroquinone reaches at least 95 degrees.

[0028] The technical solution provided by the present invention may include the following beneficial effects:

[0029] 1. When the crude tert-butylhydroquinone is dissolved, an organic acid and a reducing agent are added to effectively separate the phenol tar and quinone substances (which are present in the lower layer solution obtained after the crude solution in step C is allowed to stand and decompose) in the crude tert-butylhydroquinone that affect the product quality, thereby improving the stability of tert-butylhydroquinone, increasing the antioxidant cycle of tert-butylhydroquinone, and achieving the purpose of improving product quality.

[0030] 2. By adding a combination of an organic acid and a reducing agent during the dissolution of the crude tert-butylhydroquinone, and by introducing an inert gas into the interior of the crystallization kettle during the crystallization process, tert-butylhydroquinone is prevented from being oxidized and discolored during the purification process.

[0031] 3. In the finished product crystallization step of step F, a decolorization procedure is introduced to further thoroughly adsorb the residual phenol tar and quinone substances.

[0032] 4. Since tert-butyl hydroquinone is prepared from tert-butyl alcohol and hydroquinone as raw materials, a small amount of hydroquinone will remain in the crude tert-butyl hydroquinone. If hydroquinone exists in the tert-butyl hydroquinone product, the stability of the product will be deteriorated. After only 3 to 6 months, it will turn red and gray, and the whiteness will decrease, resulting in rework and increased labor costs. Therefore, in the first 0.5 to 1 hour of the drying step, the technical solution needs to ventilate the oven. This is because hydroquinone will evaporate during the oven drying process. The evaporated hydroquinone can be taken away by ventilation, thereby removing impurity hydroquinone, effectively improving the whiteness and stability of the tert-butyl hydroquinone product, so that the shelf life of the prepared tert-butyl hydroquinone product reaches two years, and it will not turn red and gray or agglomerate within two years. DETAILED DESCRIPTION

[0033] A method for purifying tert-butylhydroquinone comprises the following steps:

[0034] A. Evenly dissolving an organic acid in deionized water to prepare an acidity stabilizer;

[0035] B. adding crude tert-butylhydroquinone and a reducing agent to the acidity stabilizer, and heating to dissolve to obtain a crude product solution;

[0036] C. The upper layer solution obtained after the crude product solution is allowed to stand for stratification is transferred into a crystallization kettle, and an inert gas is introduced into the interior of the crystallization kettle. After cooling and crystallization, centrifugation is performed to obtain a semi-fine product of tert-butylhydroquinone;

[0037] D. uniformly dissolving the organic acid in the ethanol solution to prepare an organic acid ethanol solution;

[0038] E. adding the semi-fine tert-butylhydroquinone to the organic acid ethanol solution, heating and dissolving to obtain a fine solution;

[0039] F. Decolorizing, cooling, crystallizing, centrifuging, drying and crushing the fine product solution in sequence to obtain tert-butylhydroquinone.

[0040] Since the tert-butylhydroquinone product prepared by the existing purification method has poor stability, with a whiteness of about 78 to 85 degrees and a shelf life of only about 3 to 6 months, it needs to be used immediately after preparation and is difficult to store for a long time.

[0041] In order to improve the whiteness and shelf life of tert-butylhydroquinone, this technical solution proposes a method for purifying tert-butylhydroquinone to achieve high quality improvement of tert-butylhydroquinone finished products and extend the shelf life. Its technical focus mainly includes the following aspects:

[0042] (1) When the crude tert-butylhydroquinone is dissolved, the addition of an organic acid and a reducing agent can effectively separate the phenol tar and quinone substances (which are present in the lower layer solution obtained after the crude solution in step C is allowed to stand and decompose) in the crude tert-butylhydroquinone that affect the product quality, thereby improving the stability of tert-butylhydroquinone and increasing the antioxidant cycle of tert-butylhydroquinone, thereby achieving the purpose of improving product quality.

[0043] (2) By adding a combination of an organic acid and a reducing agent during the dissolution of the crude tert-butylhydroquinone, and by introducing an inert gas into the interior of the crystallization kettle during the crystallization process, tert-butylhydroquinone is prevented from being oxidized and discolored during the purification process.

[0044] (3) In the finished product crystallization step of step F, a decolorization procedure is introduced to further thoroughly adsorb the residual phenol tar and quinone substances, thereby further improving the whiteness of the product.

[0045] Further, in step A, the ratio of the organic acid to the deionized water is 1:(200-1000) by mass.

[0046] In step B, the addition ratio of the crude tert-butylhydroquinone, the reducing agent and the acidity stabilizer is 1: (0.01-0.015): (10-20) according to the mass ratio.

[0047] The organic acid in the acidity stabilizer has a greater impact on the purification effect. If the concentration of the organic acid is too high, it will cause obvious corrosion to the equipment and may also cause the purified product to carry organic acid. If the concentration of the organic acid is too low, it is difficult to achieve the desired purification effect. Therefore, this scheme also optimizes the addition ratio of the crude tert-butylhydroquinone, the reducing agent and the acidity stabilizer in step B.

[0048] Further, in step B, the heating temperature for heating and dissolving is 95-100°C;

[0049] In step C, the cooling temperature of the cooling crystallization is 20-50° C., and the inert gas is nitrogen; in terms of mass percentage, the oxygen content of the crystallization kettle is less than 3%.

[0050] In step B, if the temperature of heating and dissolving is too low, the crude tert-butylhydroquinone will not be completely dissolved, making it difficult to separate the phenol tar and quinone substances. In addition, since a water-based solvent is used in this purification, if the temperature of heating and dissolving is too high, the separation degree between the upper solution and the lower material (i.e., phenol tar and quinone substances) will deteriorate during the standing stratification process.

[0051] In step C, the oxygen content in the crystallization kettle is less than 3%, which is more conducive to protecting the tert-butylhydroquinone semi-fine product from oxidation.

[0052] Further, in step A, the organic acid is any one of citric acid, oxalic acid and malic acid;

[0053] In step B, the reducing agent is any one of sodium sulfite, sodium dithionite and sodium pyrosulfite.

[0054] The preferred organic acid in the technical solution is a weak acid with a certain reducing property, which can prevent the process oxidation of the tert-butylhydroquinone product according to its reducing property, and can also reduce the corrosion to the equipment.

[0055] To further illustrate, in step F, the specific steps of decolorization are: adding activated carbon to the fine solution at 70-75° C., decolorizing for 0.5 h and then filtering.

[0056] It should be noted that the activated carbon used in this scheme is any one of powdered activated carbon, granular activated carbon, indeterminate granular activated carbon and round activated carbon.

[0057] To further illustrate, in step F, the specific steps of drying are: putting the powder obtained after centrifugation into an oven for drying, the drying time is 8 to 12 hours, and the oven is ventilated for the first 0.5 to 1 hour of the drying process.

[0058] Since tert-butyl hydroquinone is prepared from tert-butyl alcohol and hydroquinone as raw materials, a small amount of hydroquinone will remain in the crude tert-butyl hydroquinone. If hydroquinone exists in the tert-butyl hydroquinone product, the stability of the product will be deteriorated. After only 3 to 6 months of storage, it will turn red and gray and the whiteness will decrease, resulting in rework and increased labor costs. Therefore, in the first 0.5 to 1 hour of the drying step, the technical solution needs to ventilate the oven. This is because hydroquinone will evaporate during the oven drying process. The evaporated hydroquinone can be taken away by ventilation, thereby removing impurity hydroquinone, effectively improving the whiteness and stability of the tert-butyl hydroquinone product, so that the shelf life of the prepared tert-butyl hydroquinone product reaches two years, and it will not turn red and gray and will not clump within two years.

[0059] Further, in step D, the raw materials of the organic acid ethanol solution include organic acid, ethanol and water, and according to the mass ratio, the preparation ratio of the organic acid, the ethanol and the water is (0.2-1): (15-50): (49-84.8);

[0060] In step E, the addition ratio of the tert-butylhydroquinone semi-fine product and the organic acid ethanol solution is 1:(2.5-5) by mass ratio, so as to completely dissolve the tert-butylhydroquinone semi-fine product.

[0061] Further, in step E, the heating temperature for heating and dissolving is 70-75°C;

[0062] In step F, the cooling temperature of the cooling crystallization is 25-30° C.; the specific steps of the centrifugation are: placing the precipitated phase after the cooling crystallization in a centrifuge, performing centrifugal washing and spinning, discarding the liquid phase after the centrifugal spinning, and taking out the solid phase to form a powder.

[0063] In step E, the present scheme also optimizes the dissolution temperature of the semi-fine tert-butylhydroquinone. If the dissolution temperature is too low, it is easy to cause incomplete dissolution; if the dissolution temperature is too high, the ethanol solution is easy to volatilize, which affects the removal of impurities in the purification process and the recovery of tert-butylhydroquinone.

[0064] To further illustrate, in step D, the organic acid is any one of citric acid, oxalic acid and malic acid.

[0065] A tert-butylhydroquinone is prepared by using the above-mentioned method for purifying tert-butylhydroquinone, and according to mass percentage, the purity of the tert-butylhydroquinone reaches at least 99.6%, and the whiteness of the tert-butylhydroquinone reaches at least 95 degrees.

[0066] The technical solution of the present invention is further illustrated below through specific implementation methods.

[0067] Example 1

[0068] A. Dissolve 1g of organic acid (citric acid) uniformly in deionized water to prepare an acidity stabilizer; wherein the preparation ratio of the organic acid to the deionized water is 1:1000.

[0069] B. Add 100 g of crude tert-butylhydroquinone (purity of 76.631 wt %, whiteness of 63.4 degrees) and a reducing agent (sodium dithionite) to the acidity stabilizer, and heat to 100° C. to dissolve to obtain a crude solution; wherein, according to the mass ratio, the addition ratio of the crude tert-butylhydroquinone, the reducing agent and the acidity stabilizer is 1:0.01:10.

[0070] C. The upper layer solution obtained after standing and stratifying the crude product solution is transferred into a crystallization kettle, and an inert gas (nitrogen) is introduced into the interior of the crystallization kettle. After cooling and crystallization, centrifugation is performed to obtain tert-butylhydroquinone semi-fine product; wherein the cooling temperature for cooling and crystallization is 20° C.; and in terms of mass percentage, the oxygen content of the crystallization kettle is less than 3%.

[0071] D. Dissolve 1 g of an organic acid (citric acid) uniformly in an ethanol solution to prepare an organic acid ethanol solution; wherein the raw materials of the organic acid ethanol solution include organic acid, ethanol and water, and the preparation ratio of the organic acid, the ethanol and the water is 1:15:60 in terms of mass ratio.

[0072] E. Add 100 g of tert-butylhydroquinone semi-fine product to the organic acid ethanol solution, heat to 70° C. to dissolve and obtain a fine product solution; wherein the addition ratio of tert-butylhydroquinone semi-fine product to the organic acid ethanol solution is 1:2.5.

[0073] F. Decolorizing, cooling, crystallizing, centrifuging, drying and crushing the fine product solution in sequence to obtain tert-butylhydroquinone; wherein:

[0074] Decolorization: Add activated carbon to the fine product solution at 70-75°C, decolorize for 0.5h and then filter;

[0075] Cooling and crystallization: The temperature of the decolorized material is reduced to 30°C and then cooled and crystallized;

[0076] Centrifugation: placing the precipitated phase after cooling and crystallization in a centrifuge for centrifugal washing and stripping, discarding the liquid phase after centrifugal stripping, and taking out the solid phase to form a powder;

[0077] Drying: The powder obtained after the centrifugation is put into an oven for drying. The drying time is 12 hours, and the oven is ventilated in the first hour of the drying process;

[0078] Crushing: After the dried powder is naturally cooled, it is crushed with a crusher to obtain tert-butylhydroquinone.

[0079] According to gas phase detection (GB 26403-2011), the content of TBHQ in the tert-butylhydroquinone product prepared in Example 1 reaches 99.689wt%. At the same time, the whiteness of the product is detected to be 95.4 degrees (detection method: take an appropriate amount of the product and press it into a cake through a mold, and detect its whiteness value on an intelligent whiteness meter); and the tert-butylhydroquinone product prepared in this embodiment does not turn red or gray within 2 years, and the whiteness is still above 95 degrees. It can be seen that the tert-butylhydroquinone product prepared in this embodiment has good product quality and good stability, and the shelf life reaches 2 years when stored in PE sealing at room temperature.

[0080] Example 2

[0081] A. Evenly dissolve 2 g of organic acid (malic acid) in deionized water to prepare an acidity stabilizer; wherein the ratio of the organic acid to the deionized water is 1:1000.

[0082] B. Add 200 g of crude tert-butylhydroquinone (purity of 74.105 wt %, whiteness of 62.8 degrees) and a reducing agent (sodium sulfite) to the acidity stabilizer, and heat to 95° C. to dissolve and obtain a crude solution; wherein, according to the mass ratio, the addition ratio of the crude tert-butylhydroquinone, the reducing agent and the acidity stabilizer is 1:0.015:15.

[0083] C. The upper layer solution obtained after standing and stratifying the crude product solution is transferred into a crystallization kettle, and an inert gas (nitrogen) is introduced into the interior of the crystallization kettle. After cooling and crystallization, centrifugation is performed to obtain tert-butylhydroquinone semi-fine product; wherein the cooling temperature for cooling and crystallization is 30° C.; and in terms of mass percentage, the oxygen content of the crystallization kettle is less than 3%.

[0084] D. Dissolve 2 g of organic acid (malic acid) uniformly in an ethanol solution to prepare an organic acid ethanol solution; wherein the raw materials of the organic acid ethanol solution include organic acid, ethanol and water, and the preparation ratio of the organic acid, the ethanol and the water is 0.5:25:80 in terms of mass ratio.

[0085] E. Add 200 g of tert-butylhydroquinone semi-fine product to the organic acid ethanol solution, heat to 75° C. to dissolve and obtain a fine product solution; wherein the addition ratio of tert-butylhydroquinone semi-fine product to the organic acid ethanol solution is 1:5.

[0086] F. Decolorizing, cooling, crystallizing, centrifuging, drying and crushing the fine product solution in sequence to obtain tert-butylhydroquinone; wherein:

[0087] Decolorization: Add activated carbon to the fine product solution at 70-75°C, decolorize for 0.5h and then filter;

[0088] Cooling and crystallization: The temperature of the decolorized material is reduced to 30°C and then cooled and crystallized;

[0089] Centrifugation: placing the precipitated phase after cooling and crystallization in a centrifuge for centrifugal washing and stripping, discarding the liquid phase after centrifugal stripping, and taking out the solid phase to form a powder;

[0090] Drying: The powder obtained after the centrifugation is put into an oven for drying. The drying time is 12 hours, and the oven is ventilated in the first hour of the drying process;

[0091] Crushing: After the dried powder is naturally cooled, it is crushed with a crusher to obtain tert-butylhydroquinone.

[0092] Through gas phase detection, the TBHQ content in the tert-butylhydroquinone product prepared in Example 2 reached 99.732wt%, and at the same time, the whiteness of the product was detected to be 96.1 degrees; and the tert-butylhydroquinone product prepared in this embodiment did not turn red or gray within 2 years, and the whiteness was still above 95 degrees. It can be seen that the tert-butylhydroquinone product prepared in this embodiment has good product quality and good stability, and the shelf life is up to 2 years when stored in PE sealed storage at room temperature.

[0093] Example 3

[0094] A. Dissolve 2 g of organic acid (oxalic acid) uniformly in deionized water to prepare an acidity stabilizer; wherein the preparation ratio of the organic acid to deionized water is 1:1000.

[0095] B. Add 200 g of crude tert-butylhydroquinone (purity of 75.034 wt %, whiteness of 65.7 degrees) and a reducing agent (sodium metabisulfite) to the acidity stabilizer, and heat to 100° C. to dissolve to obtain a crude solution; wherein, according to the mass ratio, the addition ratio of the crude tert-butylhydroquinone, the reducing agent and the acidity stabilizer is 1:0.015:20.

[0096] C. The upper layer solution obtained after standing and stratifying the crude product solution is transferred into a crystallization kettle, and an inert gas (nitrogen) is introduced into the interior of the crystallization kettle. After cooling and crystallization, centrifugation is performed to obtain tert-butylhydroquinone semi-fine product; wherein the cooling temperature for cooling and crystallization is 50° C.; and in terms of mass percentage, the oxygen content of the crystallization kettle is less than 3%.

[0097] D. Dissolve 2 g of organic acid (oxalic acid) uniformly in an ethanol solution to prepare an organic acid ethanol solution; wherein the raw materials of the organic acid ethanol solution include organic acid, ethanol and water, and the preparation ratio of the organic acid, the ethanol and the water is 0.2:50:84.8 in terms of mass ratio.

[0098] E. Add 200 g of tert-butylhydroquinone semi-fine product to the organic acid ethanol solution, heat to 70° C. to dissolve and obtain a fine product solution; wherein the addition ratio of tert-butylhydroquinone semi-fine product to the organic acid ethanol solution is 1:3.

[0099] F. Decolorizing, cooling, crystallizing, centrifuging, drying and crushing the fine product solution in sequence to obtain tert-butylhydroquinone; wherein:

[0100] Decolorization: Add activated carbon to the fine product solution at 70-75°C, decolorize for 0.5h and then filter;

[0101] Cooling and crystallization: The temperature of the decolorized material is reduced to 30°C and then cooled and crystallized;

[0102] Centrifugation: placing the precipitated phase after cooling and crystallization in a centrifuge for centrifugal washing and stripping, discarding the liquid phase after centrifugal stripping, and taking out the solid phase to form a powder;

[0103] Drying: The powder obtained after the centrifugation is put into an oven for drying. The drying time is 12 hours, and the oven is ventilated in the first hour of the drying process;

[0104] Crushing: After the dried powder is naturally cooled, it is crushed with a crusher to obtain tert-butylhydroquinone.

[0105] Through gas phase detection, the TBHQ content in the tert-butylhydroquinone product prepared in Example 3 reached 99.912wt%. At the same time, the whiteness of the product was detected to be 96.8 degrees. The tert-butylhydroquinone product prepared in this embodiment did not turn red or gray within 2 years, and the whiteness was still above 95 degrees. It can be seen that the tert-butylhydroquinone product prepared in this embodiment has good product quality and good stability, and the shelf life is up to 2 years when stored in PE sealed storage at room temperature.

[0106] The technical principle of the present invention is described above in conjunction with specific embodiments. These descriptions are only for explaining the principle of the present invention and cannot be interpreted as limiting the scope of protection of the present invention in any way. Based on the explanations herein, those skilled in the art can associate other specific implementations of the present invention without paying creative labor, and these methods will fall within the scope of protection of the present invention.

Claims

1. A method for purifying tert-butylhydroquinone, characterized in that: The following steps are involved: A. Evenly dissolving an organic acid in deionized water to prepare an acidity stabilizer; B. adding crude tert-butylhydroquinone and a reducing agent to the acidity stabilizer, and heating to dissolve to obtain a crude product solution; C. The upper layer solution obtained after the crude product solution is allowed to stand for stratification is transferred into a crystallization kettle, and an inert gas is introduced into the interior of the crystallization kettle. After cooling and crystallization, centrifugation is performed to obtain a semi-fine product of tert-butylhydroquinone; D. uniformly dissolving the organic acid in the ethanol solution to prepare an organic acid ethanol solution; E. adding the semi-fine tert-butylhydroquinone to the organic acid ethanol solution, heating and dissolving to obtain a fine solution; F. Decolorizing, cooling, crystallizing, centrifuging, drying and crushing the fine product solution in sequence to obtain tert-butylhydroquinone.

2. The method for purifying tert-butylhydroquinone according to claim 1, wherein: In step A, the ratio of the organic acid to the deionized water is 1:(200-1000) by mass. In step B, the addition ratio of the crude tert-butylhydroquinone, the reducing agent and the acidity stabilizer is 1: (0.01-0.015): (10-20) according to the mass ratio.

3. A method for purifying tert-butylhydroquinone according to claim 1, characterized in that: In step B, the heating temperature for heating and dissolving is 95-100° C.; In step C, the cooling temperature of the cooling crystallization is 20-50° C., and the inert gas is nitrogen; in terms of mass percentage, the oxygen content of the crystallization kettle is less than 3%.

4. The method for purifying tert-butylhydroquinone according to claim 1, characterized in that: In step A, the organic acid is any one of citric acid, oxalic acid and malic acid; In step B, the reducing agent is any one of sodium sulfite, sodium dithionite and sodium pyrosulfite.

5. The method for purifying tert-butylhydroquinone according to claim 1, characterized in that: In step F, the specific steps of decolorization are: adding activated carbon to the fine solution at 70-75° C., decolorizing for 0.5 h and then filtering.

6. The method for purifying tert-butylhydroquinone according to claim 1, characterized in that: In step F, the specific steps of drying are: putting the powder obtained after centrifugation into an oven for drying, the drying time is 8 to 12 hours, and the oven is ventilated for the first 0.5 to 1 hour of the drying process.

7. The method for purifying tert-butylhydroquinone according to claim 1, characterized in that: In step D, the raw materials of the organic acid ethanol solution include organic acid, ethanol and water, and the preparation ratio of the organic acid, the ethanol and the water is (0.2-1): (15-50): (49-84.8) in terms of mass ratio; In step E, the addition ratio of the tert-butylhydroquinone semi-fine product and the organic acid ethanol solution is 1:(2.5-5) in terms of mass ratio.

8. The method for purifying tert-butylhydroquinone according to claim 1, characterized in that: In step E, the heating temperature for heating and dissolving is 70-75° C.; In step F, the cooling temperature of the cooling crystallization is 25-30° C.; the specific steps of the centrifugation are: placing the precipitated phase after the cooling crystallization in a centrifuge, performing centrifugal washing and spinning, discarding the liquid phase after the centrifugal spinning, and taking out the solid phase to form a powder.

9. The method for purifying tert-butylhydroquinone according to claim 1, characterized in that: In step D, the organic acid is any one of citric acid, oxalic acid and malic acid.

10. A tert-butylhydroquinone, characterized in that: The tert-butylhydroquinone is prepared by the purification method of any one of claims 1 to 9, and the purity of the tert-butylhydroquinone reaches at least 99.6% by mass, and the whiteness of the tert-butylhydroquinone reaches at least 95 degrees.