1,3-Butanediol product and preparation method thereof, method for reducing impurities contained in acetaldehyde stream

Abstract

The present invention belongs to the technical field of cosmetic grade 1,3-butanediol products, and more particularly to a method for reducing impurities contained in acetaldehyde streams by using a 1,3-butanediol product and a preparation method thereof; the 1,3-butanediol product includes 1,3-butanediol and paraacetaldehyde; under the condition of using headspace thermal desorption-mass spectrometry to detect the content of paraacetaldehyde in 1,3-butanediol products, when the relative retention time of 1,3-butanediol in the 1,3-butanediol product is set to 1.0, the sum of the area values ​​of the peaks appearing in the relative retention time range of 0.86 to 0.88 accounts for more than 0 and less than or equal to 100ppb; and the component corresponding to the peak appearing in the relative retention time range of 0.86 to 0.88 is paraacetaldehyde. The present invention can obtain cosmetic grade 1,3-butanediol products without odor and low skin sensitization.

Description

Technical Field

[0001] The invention belongs to the technical field of cosmetic-grade 1,3-butanediol products, and in particular relates to a 1,3-butanediol product and a preparation method thereof, and a method for reducing impurities contained in an acetaldehyde stream. Background Art

[0002] 1,3-Butanediol (1,3-BG) has the reactivity of diols. Its industrial-grade products can be used as raw materials for polyester resins and alkyd resins. Its various monocarboxylic acid monoesters are excellent plasticizers for PVC resins and plastics. 1,3-BG can also react with monomers such as phthalic anhydride and maleic anhydride to produce unsaturated polyester resins. Since 1,3-BG has antibacterial effects, it is also used as an antibacterial agent for dairy and meat products. The toxicity of 1,3-BG to higher animals is very low, comparable to the toxicity of glycerol. In the field of cosmetics, 1,3-BG has long been used by formulators as a high-end moisturizer due to its transparency, colorlessness, and extremely light taste. It can also be used as an emollient, solvent, and fragrance cosolvent.

[0003] When used in the cosmetics field, 1,3-butanediol products (industrial grade products) with low odor are required. 1,3-Butanediol itself is almost odorless, but it can produce odor due to byproducts or impurities produced during the manufacturing process of 1,3-Butanediol products.

[0004] Generally speaking, the manufacturing method of 1,3-butanediol products is to condense acetaldehyde to obtain butanol aldehyde (3-hydroxybutyraldehyde), and then hydrogenate it. However, during the reaction, due to the instability of the raw materials themselves, they are easily polymerized to form characteristic substances such as polyacetaldehyde. These substances, such as impurity A (triacetaldehyde) and impurity B (tetraacetaldehyde) with the following structure, will cause the resulting 1,3-butanediol products to have odor:

[0005] .

[0006] Patent document CN 113557221A discloses the use of distillation to control the odor of 1,3-butanediol products, but the odor impurities are not completely removed. When the 1,3-butanediol product is configured into an aqueous solution, the odor still exists. Patent document CN115400706A discloses the use of steam distillation to remove the odor, but the operation process is cumbersome and energy-intensive, which is not conducive to large-scale industrial production. Patent document CN114890869A discloses the use of esterification plus extraction process to remove the odor, but the reaction steps are cumbersome and new impurities will be introduced. The final 1,3-butanediol product is difficult to meet the requirements. Patent document WO200302753A discloses a method for obtaining a 1,3-butanediol product with less odor by an extraction method. The organic solvent used as the extractant may be a ketone. However, the 1,3-butanediol product obtained by the extraction method also has the problem that it is difficult to completely eliminate the odor and produces a slight odor after long-term storage. In addition, due to the introduction of the extractant, the residue of the extractant and other problems may lead to skin sensitization problems when using 1,3-butanediol products in the cosmetic field.

[0007] In summary, there is an urgent need to develop and research odorless, low-skin-sensitizing cosmetic-grade 1,3-butylene glycol products that can be used in the cosmetics field. Summary of the invention

[0008] In view of the problems existing in the prior art, the object of the present invention is to provide a 1,3-butanediol product and a preparation method thereof, and a method for reducing impurities contained in an acetaldehyde stream; the cosmetic-grade 1,3-butanediol product is odorless and will not generate odor due to long-term storage, and has low skin sensitization.

[0009] After in-depth research, the inventors found that impurities such as polyacetaldehyde may exist in the 1,3-butanediol products obtained in production. By controlling the storage conditions of the acetaldehyde raw materials used to prepare the 1,3-butanediol products, the concentration of polyacetaldehyde impurities contained in the 1,3-butanediol products can be controlled below a certain content, so that odorless cosmetic-grade 1,3-butanediol products can be obtained, and no odor is generated after long-term storage. No allergenic substances are introduced during the entire modification process, and the skin sensitization is low.

[0010] To achieve the above object, the present invention provides the following technical solutions:

[0011] In a first aspect, a cosmetic-grade 1,3-butanediol product is provided, the 1,3-butanediol product comprising 1,3-butanediol and paraacetaldehyde;

[0012] Under the condition that the content of paraacetaldehyde in the 1,3-butanediol product is detected by headspace thermal desorption-mass spectrometry, when the relative retention time of 1,3-butanediol in the 1,3-butanediol product is set to 1.0, the sum of the area values ​​of the peaks appearing in the relative retention time range of 0.86 to 0.88 accounts for greater than 0 and less than or equal to 100 ppb (for example, 1 ppb, 2 ppb, 5 ppb, 10 ppb, 20 ppb, 30 ppb, 40 ppb, 50 ppb, 60 ppb, 70 ppb, 80 ppb, 90 ppb, 92 ppb, 95 ppb, 98 ppb); and

[0013] The peaks that appeared in the relative retention time range of 0.86 to 0.88 corresponded to polyacetaldehyde.

[0014] According to the 1,3-butanediol product provided by the present invention, in some embodiments, when the relative retention time of 1,3-butanediol in the 1,3-butanediol product is set to 1.0, the sum of the area values ​​of the peaks appearing in the relative retention time range of 0.86 to 0.88 accounts for greater than 0 and less than or equal to 80 ppb; preferably greater than 0 and less than or equal to 50 ppb.

[0015] In some embodiments, the content of polyacetaldehyde in the 1,3-butanediol product is detected by headspace thermal desorption-mass spectrometry, which includes:

[0016] You can use HSTD headspace thermal desorption multifunctional sampler: Chengdu Kelin Analysis Technology Co., Ltd.;

[0017] (1) Headspace conditions

[0018] Oven temperature: 70℃,

[0019] Needle temperature: 100℃,

[0020] Transmission temperature: 200℃;

[0021] Pressurization replacement time: 30s;

[0022] Injection time: 120s;

[0023] Air defense time: 30s;

[0024] Constant temperature time: 30min;

[0025] Cycle time: 42min;

[0026] Pressure: 120kPa;

[0027] Carrier gas: helium;

[0028] (2) Thermal desorption conditions

[0029] Purge time: 60s;

[0030] First-stage desorption time: 2.1min;

[0031] Cold hydrazine heating time: 8.0min;

[0032] Injection time: 100s;

[0033] Cycle time: 43min;

[0034] Secondary desorption temperature: 300℃;

[0035] Primary desorption temperature: 110℃;

[0036] Cold hydrazine adsorption temperature: -30℃;

[0037] Valve temperature: 200℃;

[0038] Transmission temperature: 220℃;

[0039] Carrier gas pressure: 100kPa;

[0040] Adsorption flow rate: 35mL / min;

[0041] Flow rate of split 1: 5 mL / min;

[0042] Flow rate of split 2: 5 mL / min;

[0043] (3) Gas chromatography analysis conditions

[0044] Available gas chromatograph: Shimadzu GC-2010 Plus gas chromatograph;

[0045] Analytical column: HP-VOC manufactured by Agilent Technologies (length 60 m, inner diameter 0.32 mm, liquid film thickness 1.8 μm) as gas chromatography column, stationary phase (6%-cyanopropyl-phenyl)-methylpolysiloxane);

[0046] Carrier gas: helium;

[0047] Carrier gas flow rate: 1.5 mL / min;

[0048] Control mode: constant flow;

[0049] Vaporization chamber temperature: 250℃;

[0050] Heating conditions: The column temperature was set at 50°C as the starting temperature, maintained for 2 min, then raised to 80°C at a rate of 5°C / min, then raised to 260°C at a rate of 15°C / min, and maintained at 240°C for 15 min.

[0051] Split ratio: no split;

[0052] (4) Conditions for mass spectrometry analysis

[0053] Available mass spectrometer: Shimadzu GCMS-QP2020 mass spectrometer;

[0054] Ionization mode: EI; Measurement type: full scan;

[0055] Ion source temperature: 230°C;

[0056] Quadrupole temperature: 150°C;

[0057] Electron energy: 70 eV;

[0058] Scan start quality: 29;

[0059] Scan end quality: 600;

[0060] Calibration curve: When using a paraldehyde standard solution to prepare data analysis, use extracted ion chromatogram (EIC) to confirm the EIC peak area of ​​paraldehyde (EIC: m / z 89) that appears in the relative retention time range of 0.86 to 0.88 when the relative retention time of 1,3-butanediol is set to 1.0;

[0061] (5) Preparation of standard solution and drawing of standard curve

[0062] Add paraldehyde to water to prepare a paraldehyde standard solution with a concentration range of 10-100 µg / L; use a 10 mL pipette to transfer 10 mL of the prepared standard solution into a 20 mL headspace sample bottle, seal it, and perform the test according to steps (1) to (4);

[0063] The gas-mass spectrometer was obtained in the SCAN mode, and the characteristic ions 89 and 117 were extracted to determine the retention position of triacetaldehyde. The peak of characteristic ion 89 was integrated to draw a standard curve;

[0064] (6) Testing of samples to be tested

[0065] Weigh 2 g (accurate to 0.1 mg) of the 1,3-butanediol product to be tested into a 20 mL headspace sample bottle. Use a 10 mL pipette to transfer 8 mL of ultrapure water into the headspace bottle, seal it, and perform the test according to steps (1) to (4).

[0066] The 1,3-butanediol product of the present invention contains polyacetaldehyde compounds as components corresponding to the peaks appearing in the relative retention time range of 0.86 to 0.88. As polyacetaldehyde compounds, their structure can be but is not limited to the following structure:

[0067] .

[0068] In some embodiments, the polyacetaldehyde is paraldehyde and / or tetraacetaldehyde.

[0069] In a second aspect, a method for reducing impurities in an acetaldehyde stream during the production of a cosmetic-grade 1,3-butanediol product is provided, wherein the content of polyacetaldehyde in the acetaldehyde stream as a raw material is greater than 0 and less than or equal to 2 wt % (e.g., 0.01 wt %, 0.02 wt %, 0.05 wt %, 0.08 wt %, 0.1 wt %, 0.2 wt %, 0.3 wt %, 0.4 wt %, 0.5 wt %, 0.6 wt %, 0.8 wt %, 1.0 wt %, 1.2 wt %, 1.4 wt %, 1.5 wt %, 1.6 wt %, 1.8 wt %), preferably greater than 0 and less than or equal to 1 wt %, and more preferably greater than 0 and less than or equal to 0.5 wt %.

[0070] According to the method provided by the present invention, in some embodiments, during the storage of the acetaldehyde stream as a raw material, the storage time is greater than 0 and less than or equal to 90 days (for example, 0.5 days, 1 day, 2 days, 4 days, 5 days, 8 days, 10 days, 15 days, 20 days, 25 days, 30 days, 35 days, 40 days, 50 days, 55 days, 60 days, 70 days, 80 days, 85 days), preferably greater than 0 and less than or equal to 45 days, and more preferably greater than 0 and less than or equal to 15 days.

[0071] In some embodiments, during the storage of the acetaldehyde stream as a raw material, the storage temperature is greater than 0 and less than or equal to 50°C (for example, 1°C, 2°C, 5°C, 6°C, 8°C, 10°C, 12°C, 15°C, 20°C, 25°C, 30°C, 35°C, 40°C, 45°C, 48°C), preferably greater than 0 and less than or equal to 30°C.

[0072] In some embodiments, during the storage of the acetaldehyde stream as the raw material, the storage method is isolated from air, preferably nitrogen-sealed storage (i.e., nitrogen-sealed storage).

[0073] In a third aspect, a method for preparing the 1,3-butanediol product as described above is provided, wherein the method adopts an acetaldehyde condensation hydrogenation process;

[0074] The content of paraacetaldehyde in the acetaldehyde stream as a raw material is greater than 0 and less than or equal to 2 wt % (for example, 0.05 wt %, 0.1 wt %, 0.15 wt %, 0.2 wt %, 0.25 wt %, 0.3 wt %, 0.35 wt %, 0.4 wt %, 0.45 wt %, 0.5 wt %, 0.6 wt %, 0.8 wt %, 1.0 wt %, 1.2 wt %, 1.4 wt %, 1.5 wt %, 1.6 wt %, 1.8 wt %), preferably greater than 0 and less than or equal to 1 wt %, and more preferably greater than 0 and less than or equal to 0.5 wt %.

[0075] The preparation method of the 1,3-butanediol product can adopt the conventional acetaldehyde condensation hydrogenation process in the art.

[0076] In the present invention, the preparation method of the 1,3-butanediol product may be a known technology, for example, reference may be made to patents CN110790634B, US5345004, US6376725, US6900360, and CN1558890A.

[0077] In some specific embodiments, the steps of the preparation method may be, for example:

[0078] 1) Acetaldehyde condensation: in the presence of an alkaline catalyst (such as sodium hydroxide aqueous solution, potassium hydroxide aqueous solution, generally sodium hydroxide aqueous solution), acetaldehyde undergoes a condensation reaction to obtain a reaction mixture containing 3-hydroxybutyraldehyde; then, unreacted acetaldehyde is removed by nitrogen stripping or short-path evaporation to obtain a hydrogenation raw material liquid; wherein, the condensation reaction temperature can be 0 to 30°C, preferably 10 to 15°C (such as 12°C, 13°C, 14°C); the reaction time can be selected conventionally in the art;

[0079] 2) Hydrogenation step: The hydrogenation raw material liquid obtained in step 1) is subjected to a hydrogenation reaction to obtain a 1,3-butanediol reaction liquid, wherein the hydrogenation catalyst is selected from a catalyst containing nickel and / or cobalt (such as Raney nickel, Raney cobalt, supported nickel and supported cobalt catalysts); wherein the reaction temperature may be 110-130°C, for example, 115°C, 120°C, 125°C, and the reaction pressure may be 2-20MPa (gauge pressure), for example, 4MPa, 5MPa, 8MPa, 10MPa, 12MPa, 15MPa, 18MPa; and the reaction space velocity may be a conventional choice in the art, which will not be described in detail here;

[0080] 3) Separation step: The 1,3-butanediol reaction liquid obtained in step 2) is subjected to distillation separation and deodorization treatment to obtain a cosmetic grade 1,3-butanediol product; wherein the distillation separation operation and its process conditions, and deodorization treatment can be conventional means in the art and will not be described in detail here.

[0081] The source of the acetaldehyde stream used as a raw material in the production of the 1,3-butanediol product of the present invention is not particularly limited, and examples thereof include: an acetaldehyde stream synthesized by oxidation of ethanol, and an acetaldehyde stream synthesized by oxidation of ethylene. The acetaldehyde stream used as a raw material is preferably an acetaldehyde stream synthesized by further oxidation of ethanol obtained by biological fermentation.

[0082] The inventors' research found that the polyacetaldehyde compounds contained in the 1,3-butanediol product are mainly brought in as the raw material acetaldehyde stream, and the amount produced during the condensation hydrogenation process of the acetaldehyde stream is relatively small. Therefore, it is necessary to control the polyacetaldehyde content in the raw material acetaldehyde stream to be no higher than 2%.

[0083] The acetaldehyde stream as a raw material is unstable in nature. If the temperature is too high or the storage time is too long during storage, or if it is exposed to air, a polymerization reaction will occur to generate polyacetaldehyde compounds such as trimeraldehyde or tetrameraldehyde, which will be further introduced into the 1,3-butanediol product and cause polyacetaldehyde residues in the 1,3-butanediol product, affecting the product odor and causing skin sensitization. In order to meet the use requirements of the acetaldehyde stream, according to the preparation method provided by the present invention, in some embodiments, the storage time of the acetaldehyde stream as a raw material during storage is greater than 0 and less than or equal to 90 days, preferably greater than 0 and less than or equal to 45 days, and more preferably greater than 0 and less than or equal to 15 days.

[0084] According to the preparation method provided by the present invention, in some embodiments, during the storage of the acetaldehyde stream as the raw material, the storage temperature is greater than 0 and less than or equal to 50°C, preferably greater than 0 and less than or equal to 30°C.

[0085] According to the preparation method provided by the present invention, in some embodiments, during the storage of the acetaldehyde stream as the raw material, the storage method is isolated from air, preferably nitrogen-sealed storage.

[0086] The present invention controls the content of polyacetaldehyde in the acetaldehyde stream raw material by controlling the storage method and storage conditions of the acetaldehyde stream as a raw material, thereby ensuring that the content of polyacetaldehyde compounds in the final 1,3-butanediol product is lower than 100 ppb or even undetectable, and the odor detection and skin sensitization of the obtained cosmetic-grade 1,3-butanediol product can meet downstream requirements. DETAILED DESCRIPTION

[0087] In order to understand the technical features and content of the present invention in detail, the preferred embodiments of the present invention will be described in more detail below. Although the preferred embodiments of the present invention are described in the embodiments, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments described herein. For those who do not specify specific conditions in the embodiments, they are carried out according to normal conditions or the conditions recommended by the manufacturer.

[0088] In the following examples and comparative examples, the sources of some reagents or raw materials used, if the manufacturer of the reagents or raw materials is not indicated, are conventional products that can be purchased from the market.

[0089]

Odor test

[0090] The 1,3-butanediol products prepared in the respective Examples and Comparative Examples were subjected to odor tests according to the following evaluation methods.

[0091] (1) Odor evaluation method:

[0092] The 1,3-butanediol products prepared in the embodiments and comparative examples were mixed with water to prepare 10 g of aqueous solutions with a 10 wt% 1,3-butanediol product content, respectively, and then added to a 20 mL wide-mouth glass bottle and closed with a lid, and stirred vigorously at room temperature for 1 minute; the lid was opened and the odor was smelled, and compared with the standard odor sample to determine the odor level of the sample; the number of evaluators was set to 10, and the average score of each person's evaluation result was calculated as the odor score.

[0093] (2) Preparation of standard odor samples:

[0094] 1,3-Butanediol manufactured by Daicel was mixed with water to prepare a 10 wt% 1,3-Butanediol aqueous solution as a standard odor sample. According to Table 1 below, 100 g of five standard samples with different odor intensities were prepared and then placed in 200 ml wide-mouth flasks.

[0095] Table 1 Odor standard samples and their corresponding odor levels

[0096]

[0097] (3) Odor evaluation results

[0098] The score of the standard odor sample prepared in step (2) above is set to 5, and then the odor level of the 1,3-butanediol products prepared in each embodiment and comparative example is evaluated according to the process described in step (1) based on the standard odor sample.

[0099] Odor level:

[0100] Level 1: Feeling of stench;

[0101] Level 2: between 1 and 3;

[0102] Level 3: A slight odor is felt;

[0103] Level 4: between 3 and 5;

[0104] Level 5: No odor is detected.

[0105]

Skin sensitization test

[0106] The 1,3-butanediol products obtained in each of the Examples and Comparative Examples were evaluated for skin sensitization according to the following operation method.

[0107] (1) Preparation of test substances:

[0108] If the suspected allergen is a liquid, the patch test will be conducted after diluting it with gradient concentrations, gradually increasing the concentration; cosmetics and topical medications can be directly patch tested; 30 people will be randomly selected as samples.

[0109] (2) Conduct a patch test:

[0110] Use a commercially available aluminum dish and stick it on non-allergenic porous tape. When using it, prepare the suspected allergen in an appropriate concentration and put a small amount of the suspected allergen in the aluminum dish, then apply it to both sides of the back or the inner side of the forearm, and observe the reaction after 48 hours. However, if irritation or a positive reaction occurs within 48 hours, remove the test substance immediately. If multiple suspected patch tests are performed at the same time, they need to be arranged in order and marked. Generally, the observation is continuous for 2-3 days.

[0111] (3) Result determination:

[0112] Negative: - means negative, the patient has no reaction at the application site;

[0113] Suspected positive: ± indicates doubt, with subjective itching or slight redness;

[0114] Weak positive: + indicates weak positive, manifested as simple erythema, conscious itching, etc.;

[0115] Positive: ++ indicates positive, manifested as redness, swelling, and papules;

[0116] Strong positive: +++ indicates strong positive, manifested by significant redness and swelling, and symptoms such as papules and blisters;

[0117] Very strong positive: ++++Expresses strong positivity, manifested as significant redness, swelling, blisters and erosions.

[0118] [Testing the impurity content in acetaldehyde raw materials using GC analysis]

[0119] Analytical device: 8890A gas chromatography system manufactured by Agilent Technologies;

[0120] Sample preparation: dilute the acetaldehyde sample to be tested to 2 mL with ethanol, and then use the dilution as the test sample;

[0121] Detector: FID hydrogen ion flame detector;

[0122] Detection temperature: 260℃;

[0123] Sample inlet temperature: 260°C;

[0124] Analytical column: HP-INNOWAX (length 60 m, inner diameter 0.250 mm, film thickness 0.25 μm) manufactured by Agilent Technologies was used as the gas chromatography column;

[0125] Heating conditions: The column temperature was set at 50°C as the starting temperature, maintained for 0.5 min, then raised to 200°C at a rate of 15°C / min, then raised to 240°C at a rate of 20°C / min, and maintained at 240°C for 20 min.

[0126] Control mode: constant flow;

[0127] Split ratio: 50:1;

[0128] Injection volume: 0.2 µL;

[0129] Nitrogen flow rate: 30 mL / min;

[0130] Hydrogen flow rate: 40 mL / min;

[0131] Air flow rate: 400mL / min;

[0132] Exhaust gas purge volume: 25ml / min.

[0133] In the above GC analysis, when the relative retention time of pure acetaldehyde is set to 1.0, the sum of the area values ​​of the peaks appearing in the relative retention time range of 2.0 to 2.5 is determined to be the content of impurities in the acetaldehyde sample to be measured.

[0134] [Purity test of 1,3-butanediol products using GC analysis]

[0135] Analytical device: 8890A gas chromatography system manufactured by Agilent Technologies;

[0136] Sample preparation: Dilute the 1,3-butanediol sample to be tested to 2 mL with ethanol, and use the dilution as the test sample;

[0137] Detector: FID hydrogen ion flame detector;

[0138] Detection temperature: 260℃;

[0139] Sample inlet temperature: 260°C;

[0140] Analytical column: HP-INNOWAX (length 60 m, inner diameter 0.250 mm, film thickness 0.25 μm) manufactured by Agilent Technologies was used as the gas chromatography column;

[0141] Heating conditions: The column temperature was set at 50°C as the starting temperature, maintained for 0.5 min, then raised to 200°C at a rate of 15°C / min, then raised to 240°C at a rate of 20°C / min, and maintained at 240°C for 20 min.

[0142] Control mode: constant flow;

[0143] Split ratio: 50:1;

[0144] Injection volume: 0.2 µL;

[0145] Nitrogen flow rate: 30 mL / min;

[0146] Hydrogen flow rate: 40 mL / min;

[0147] Air flow rate: 400mL / min;

[0148] Exhaust gas purge volume: 25ml / min.

[0149] In the above GC analysis, the area normalization method was used to determine the area value ratio of the peak where 1,3-butanediol appeared.

[0150] [Detection of polyacetaldehyde content in 1,3-butanediol products by headspace thermal desorption-mass spectrometry]

[0151] 1.1 HSTD Headspace Thermal Desorption Multifunctional Sampler: Chengdu Kelin Analytical Technology Co., Ltd.;

[0152] (1) Headspace conditions

[0153] Oven temperature: 70℃;

[0154] Needle temperature: 100℃;

[0155] Transmission temperature: 200℃;

[0156] Pressurization replacement time: 30s;

[0157] Injection time: 120s;

[0158] Air defense time: 30s;

[0159] Constant temperature time: 30min;

[0160] Cycle time: 42min;

[0161] Pressure: 120kPa;

[0162] Carrier gas: helium;

[0163] (2) Thermal desorption conditions

[0164] Purge time: 60s;

[0165] First-stage desorption time: 2.1min;

[0166] Cold hydrazine heating time: 8.0min;

[0167] Injection time: 100s;

[0168] Cycle time: 43min;

[0169] Secondary desorption temperature: 300℃;

[0170] Primary desorption temperature: 110℃;

[0171] Cold hydrazine adsorption temperature: -30℃;

[0172] Valve temperature: 200℃;

[0173] Transmission temperature: 220℃;

[0174] Carrier gas pressure: 100kPa;

[0175] Adsorption flow rate: 35mL / min;

[0176] Split 1: 5 mL / min;

[0177] Split 2: 5 mL / min;

[0178] 1.2 Gas chromatography analysis: Shimadzu GC-2010 Plus gas chromatograph

[0179] Analytical column: HP-VOC (length 60 m, inner diameter 0.32 mm, liquid film thickness 1.8 μm) manufactured by Agilent Technologies was used as the gas chromatography column, and the stationary phase was (6%-cyanopropyl-phenyl)-methylpolysiloxane;

[0180] Carrier gas: helium;

[0181] Carrier gas flow rate: 1.5 mL / min;

[0182] Control mode: constant flow;

[0183] Vaporization chamber temperature: 250℃;

[0184] Heating conditions: The column temperature was set at 50°C as the starting temperature, maintained for 2 min, then raised to 80°C at a rate of 5°C / min, then raised to 260°C at a rate of 15°C / min, and maintained at 240°C for 15 min.

[0185] Split ratio: no split;

[0186] 1.3 Mass spectrometry detection: Shimadzu GCMS-QP2020 mass spectrometer

[0187] Ionization mode: EI;

[0188] Assay type: Full scan;

[0189] Ion source temperature: 230°C;

[0190] Quadrupole temperature: 150°C;

[0191] Electron energy: 70 eV;

[0192] Scan start quality: 29;

[0193] Scan end quality: 600;

[0194] Calibration curve: Use paraldehyde standard to prepare the calibration curve;

[0195] In data analysis, extracted ion chromatograms (EIC) were used to confirm the EIC peak area (EIC: m / z 89) of paraldehyde that appeared in the relative retention time range of 0.86 to 0.88 when the relative retention time of 1,3-butanediol was set to 1.0;

[0196] 1.4 Preparation of standard solution and drawing of standard curve

[0197] Add paraldehyde to water to prepare a paraldehyde standard solution with a concentration range of 10-100 µg / L; use a 10 mL pipette to transfer 10 mL of the prepared standard solution into a 20 mL headspace sample bottle, seal it, and perform the test according to the above steps;

[0198] The gas-mass spectrometer was obtained in the SCAN mode, and the characteristic ions 89 and 117 were extracted to determine the retention position of triacetaldehyde. The peak of characteristic ion 89 was integrated to draw the standard curve;

[0199] 1.5 Sample testing

[0200] Weigh 2 g (accurate to 0.1 mg) of the 1,3-butanediol product prepared in each example and comparative example as the sample to be tested and place it in a 20 mL headspace sample bottle. Use a 10 mL pipette to transfer 8 mL of ultrapure water, add it to the headspace bottle, seal it, and test it according to the process described in 1.1 to 1.3 above.

[0201] Refining of acetaldehyde raw materials:

[0202] The commercially available acetaldehyde stream is an acetaldehyde aqueous solution with a mass concentration of 40%. In order to obtain a high-purity acetaldehyde stream, the commercially available acetaldehyde aqueous solution needs to be distilled and refined. The specific operation is:

[0203] 500 g of 40% acetaldehyde aqueous solution was added into a 1000 mL three-necked flask, a magnetic rod was put into the flask, and the flask was placed in a constant temperature oil bath. The two side ports of the three-necked flask were connected to a ground-mouth thermometer sleeve (thermometer range 200°C) and a ground-mouth glass stopper, respectively, and the middle port was connected to a distillation column. The distillation column was filled with θ-ring fillers, which was equivalent to 10 theoretical plates, and the distillation process was at normal pressure. The product collection bottle was a 500 mL jacketed flask, and the distillation head shell and the jacketed flask were connected in series and then connected to a low-temperature constant temperature cold bath, and the temperature of the cold bath was set to 0°C.

[0204] Turn on the constant temperature cold bath, and after the temperature drops to 0°C, set the oil bath temperature to 80°C and start stirring and heating; set the reflux ratio controller to full reflux; after the oil bath display temperature reaches 80°C, the thermometer indicates a temperature of 75°C; when condensate appears at the top of the distillation tower, the top temperature is 21°C, at this time adjust the reflux ratio to 1:1, start collecting the refined acetaldehyde stream and set it aside.

[0205] [Example 1]

[0206] 1. Storage of acetaldehyde stream as raw material:

[0207] A fresh refined acetaldehyde stream was placed in a pressure container, and after nitrogen replacement, the storage temperature was controlled to be 30°C. After storage for 15 days, it was taken out of the pressure container, and then the content of polyacetaldehyde in the refined acetaldehyde stream before and after storage was detected and analyzed by GC analysis. It was found that before storage, the content of polyacetaldehyde in the refined acetaldehyde stream was 0.001wt%; after storage, the content of polyacetaldehyde in the refined acetaldehyde stream was 0.3wt%.

[0208] 2. Preparation of cosmetic grade 1,3-butanediol products:

[0209] (S1) Acetaldehyde condensation step

[0210] 50 g of a 1 wt% sodium hydroxide aqueous solution was added dropwise to 500 g of the stored refined acetaldehyde stream obtained as above for 4 h, and the condensation reaction temperature was controlled at 10-15° C. by a cold bath. After the addition was completed, the reaction was continued for 3 h, and then acetic acid was added to the system to neutralize the material to neutrality, and unreacted acetaldehyde was recovered by short-path evaporation to obtain a hydrogenation raw material liquid (i.e., a condensation liquid containing 3-hydroxybutyraldehyde);

[0211] (S2) Hydrogenation step

[0212] 356.7 g of the above-obtained hydrogenation raw liquid (containing the condensation liquid of 3-hydroxybutyraldehyde) and 12.49 g of Raney nickel catalyst (Raney 6800, purchased from GRACE) were placed in a 1 L reactor, and hydrogenation reaction was carried out at a reaction temperature of 125° C. and a reaction pressure of 15 MPa (gauge pressure). After the reaction was completed, a crude hydrogenation reaction liquid was obtained;

[0213] (S3) Separation and purification step

[0214] The crude hydrogenation reaction liquid obtained as above is passed into a distillation tower for distillation separation. The distillation tower has 30 plates. Low-boiling point compounds such as ethanol and water are first collected at a pressure of 20 kPa, and then the pressure is reduced to 2.0 kPa (absolute pressure) to collect 1,3-butanediol product with a purity of ≥99.7%.

[0215] 100 g of the 1,3-butanediol product obtained by distillation separation, 100 g of water and 60 g of methyl isobutyl ketone were added to a 500 mL separatory funnel, shaken for 2 to 3 minutes, and then allowed to stand for 5 minutes to allow the aqueous layer and the organic layer to separate; 6 g of methyl isobutyl ketone was further added to the separated aqueous layer, and the same phase separation operation as described above was repeated twice; the extracted aqueous layer was added to a three-necked flask, and dehydrated and concentrated at an oil bath temperature of 150° C. and a pressure of 8 kPa for 30 minutes to obtain 95 g of a 1,3-butanediol product.

[0216] 3. Performance test:

[0217] The content of polyacetaldehyde in the obtained 1,3-butanediol product was detected by headspace thermal desorption-mass spectrometry; the test results showed that the sum of the area values ​​of the peaks appearing in the relative retention time range of 0.86~0.88 accounted for 46ppb, and the components corresponding to the peaks appearing in the relative retention time range of 0.86~0.88 were polyacetaldehyde compounds.

[0218] The purity of the obtained 1,3-butanediol product was tested by GC analysis, and the test results showed that the area ratio of the peak of 1,3-butanediol was 99.86%.

[0219] The odor test of the obtained 1,3-butanediol product showed that the odor score was 5.

[0220] The skin sensitization test of the obtained 1,3-butanediol product was carried out, and the results showed that all 30 people were negative.

[0221] [Examples 2 to 6]

[0222] 1. Storage of acetaldehyde stream as raw material:

[0223] The storage container and storage method are the same as those in Example 1, except that the storage temperature and storage time are changed. Please see Table 2 for specific conditions.

[0224] 2. Preparation of cosmetic grade 1,3-butanediol products:

[0225] The preparation process and steps are the same as in Example 1.

[0226] 3. Performance test:

[0227] The test steps are the same as in Example 1, and the results are shown in Table 3.

[0228] [Comparative Example 1]

[0229] 1. Storage of acetaldehyde stream as raw material:

[0230] The storage container, storage method and storage conditions are the same as those in Example 1, except that the storage temperature is replaced with 70°C.

[0231] 2. Preparation of cosmetic grade 1,3-butanediol products:

[0232] The preparation process and steps are the same as in Example 1.

[0233] 3. Performance test:

[0234] The test steps are the same as in Example 1, and the results are shown in Table 3.

[0235] [Comparative Example 2]

[0236] 1. Storage of acetaldehyde stream as raw material:

[0237] The storage container, storage method and storage conditions are the same as those in Example 1, except that the storage time is replaced with 180 days.

[0238] 2. Preparation of cosmetic grade 1,3-butanediol products:

[0239] The preparation process and steps are the same as in Example 1.

[0240] 3. Performance test:

[0241] The test steps are the same as in Example 1, and the results are shown in Table 3.

[0242] [Comparative Example 3]

[0243] 1. Storage of acetaldehyde stream as raw material:

[0244] The storage container, storage method and storage conditions are the same as those in Example 1, except that the storage container is not replaced with nitrogen.

[0245] 2. Preparation of cosmetic grade 1,3-butanediol products:

[0246] The preparation process and steps are the same as in Example 1.

[0247] 3. Performance test:

[0248] The test steps are the same as in Example 1, and the results are shown in Table 3.

[0249] Table 2 Storage conditions and results of acetaldehyde stream in Examples 2-6 and Comparative Examples 1-3

[0250]

[0251] Table 3 Test results of 1,3-butanediol products obtained in Examples 2-6 and Comparative Examples 1-3

[0252]

[0253] The embodiments of the present invention control the content of polyacetaldehyde in the acetaldehyde stream raw material by controlling the storage method and storage conditions of the acetaldehyde stream as the raw material, thereby ensuring that the content of polyacetaldehyde compounds in the final 1,3-butanediol product is lower than 100 ppb or even undetectable; this enables the odor evaluation and skin sensitization of the obtained cosmetic-grade 1,3-butanediol product to meet downstream requirements.

[0254] Comparative Examples 1-3 did not reasonably control the storage method and storage conditions of the acetaldehyde stream of the raw materials, resulting in a high content of polyacetaldehyde compounds in the final 1,3-butanediol product, which was above 150 ppb, and could even reach above 500-800 ppb, seriously affecting the odor evaluation and skin sensitization of the obtained cosmetic-grade 1,3-butanediol product, and failing to meet downstream requirements.

[0255] The embodiments of the present invention have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes will be apparent to those skilled in the art without departing from the spirit of the present invention.

Claims

1. A method for reducing impurities in an acetaldehyde stream during the production of a cosmetic grade 1,3-butanediol product, characterized in that: In the acetaldehyde stream used as a raw material, the content of polyacetaldehyde is greater than 0 and less than or equal to 2wt%; During the storage of the acetaldehyde stream as a raw material, the storage time is greater than 0 and less than or equal to 90 days; the storage temperature is greater than 0 and less than or equal to 50° C.; During the storage process of the acetaldehyde stream as the raw material, the storage method is to isolate it from air.

2. The method according to claim 1, characterized in that The 1,3-butanediol product comprises 1,3-butanediol and polyacetaldehyde; Under the condition that the content of paraacetaldehyde in the 1,3-butanediol product is detected by headspace thermal desorption-mass spectrometry, when the relative retention time of 1,3-butanediol in the 1,3-butanediol product is set to 1.0, the sum of the area values ​​of the peaks appearing in the relative retention time range of 0.86 to 0.88 accounts for more than 0 and less than or equal to 100 ppb; and The peaks that appeared in the relative retention time range of 0.86 to 0.88 corresponded to polyacetaldehyde.

3. The method according to claim 2, characterized in that When the relative retention time of 1,3-butanediol in the 1,3-butanediol product is set to 1.0, the sum of the area values ​​of the peaks appearing in the relative retention time range of 0.86 to 0.88 accounts for more than 0 and less than or equal to 80 ppb.

4. The method according to claim 2, characterized in that The content of polyacetaldehyde in the 1,3-butanediol product is detected by headspace thermal desorption-mass spectrometry, which includes: (1) Headspace conditions Oven temperature: 70℃; Needle temperature: 100℃; Transmission temperature: 200℃; Pressurization replacement time: 30s; Injection time: 120s; Air defense time: 30s; Constant temperature time: 30min; Cycle time: 42min; Pressure: 120kPa; Carrier gas: helium; (2) Thermal desorption conditions Purge time: 60s; First-stage desorption time: 2.1min; Cold hydrazine heating time: 8.0min; Injection time: 100s; Cycle time: 43min; Secondary desorption temperature: 300℃; Primary desorption temperature: 110℃; Cold hydrazine adsorption temperature: -30℃; Valve temperature: 200℃; Transmission temperature: 220℃; Carrier gas pressure: 100kPa; Adsorption flow rate: 35mL / min; Split 1: 5 mL / min; Split 2: 5 mL / min; (3) Gas chromatography analysis conditions Carrier gas: helium; Carrier gas flow rate: 1.5 mL / min; Control mode: constant flow; Vaporization chamber temperature: 250℃; Heating conditions: The column temperature was set at 50°C as the starting temperature, maintained for 2 min, then raised to 80°C at a rate of 5°C / min, then raised to 260°C at a rate of 15°C / min, and maintained at 240°C for 15 min. Split ratio: no split; (4) Conditions for mass spectrometry analysis Ionization mode: EI; Measurement type: full scan; Ion source temperature: 230°C; Quadrupole temperature: 150°C; Electron energy: 70 eV; Scan start quality: 29; Scan end quality: 600; (5) Preparation of standard solution and drawing of standard curve Add paraldehyde to water to prepare a paraldehyde standard solution with a concentration range of 10-100 µg / L; use a 10 mL pipette to transfer 10 mL of the prepared standard solution into a 20 mL headspace sample bottle, seal it, and perform the test according to steps (1) to (4); The gas-mass spectrometer was obtained in the SCAN mode, and the characteristic ions 89 and 117 were extracted to determine the retention position of triacetaldehyde. The peak of characteristic ion 89 was integrated to draw a standard curve; (6) Testing of samples to be tested Weigh 2 g of the 1,3-butanediol product to be tested into a 20 mL headspace sample bottle. Use a 10 mL pipette to transfer 8 mL of ultrapure water into the headspace bottle, seal it, and perform the test according to steps (1) to (4).

5. The method according to claim 2, characterized in that: The polyacetaldehyde is paraldehyde and / or tetraacetaldehyde.

6. The method according to claim 1, characterized in that The preparation method of the 1,3-butanediol product adopts an acetaldehyde condensation hydrogenation process; The content of polyacetaldehyde in the acetaldehyde stream as a raw material is greater than 0 and less than or equal to 2 wt %.

7. The method according to claim 6, characterized in that The storage time of the acetaldehyde stream as the raw material is greater than 0 and less than or equal to 90 days during the storage process; and / or During the storage of the acetaldehyde stream as the raw material, the storage temperature is greater than 0 and less than or equal to 50°C.

8. The method according to claim 6, characterized in that During the storage process of the acetaldehyde stream as the raw material, the storage method is to isolate it from air.

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