A refining process for 3-phenoxypropane-1,2-diol

Abstract

A refining process for 3-phenoxypropane-1,2-diol, wherein a crude 3-phenoxypropane-1,2-diol product is dissolved, filtered under reduced pressure, rinsed, refluxed in a water bath, recrystallized and dried, and the entire process conditions are optimized, so that the purified 3-phenoxypropane-1,2-diol product has a higher purity; the purified 3-phenoxypropane-1,2-diol product is analyzed by gas chromatography, and the purity of the 3-phenoxypropane-1,2-diol is greater than 99.9%, no phenol is detected, and the impurity content is less than 0.1%; the overall process of the invention is simple, the cost is low, and the prepared product has high purity and low loss rate.

Description

Technical Field

[0001] The invention relates to the technical field of fine chemical production, and in particular to a refining process of 3-phenoxypropane-1,2-diol. Background Art

[0002] 3-Phenoxypropane-1,2-diol, also known as phenoxypropylene glycol, is a natural product found in the annual herbaceous plant Psoralea corylifolia. It is a white solid and is often used as an important organic synthesis intermediate. In addition, the application range of 3-phenoxypropane-1,2-diol also covers inks, perfumes, thermochromic materials, drug synthesis and other fields, showing its wide practical value.

[0003] 3-Phenoxypropane-1,2-diol generally uses phenol as raw material. During the synthesis process, due to the limitations of reaction conditions, raw material purity and separation and purification technology, the final product often inevitably contains trace amounts of phenol and other organic or inorganic impurities that affect the product quality. The existing technology has not been able to solve this problem. Summary of the invention

[0004] In order to overcome the defects of the above-mentioned prior art, the purpose of the present invention is to provide a refining process for 3-phenoxypropane-1,2-diol, by dissolving the crude 3-phenoxypropane-1,2-diol product, filtering under reduced pressure, eluting, refluxing in a water bath, recrystallizing and drying, and combining the optimization of the entire process conditions, the refined 3-phenoxypropane-1,2-diol product has high purity, no phenol is detected, the impurity content is low, and the product loss rate is low.

[0005] To achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0006] A refining process for 3-phenoxypropane-1,2-diol specifically comprises the following steps:

[0007] Step 1: Mix 1 part of crude 3-phenoxypropane-1,2-diol and 3 to 8 parts of deionized water by weight, heat and stir at 50±5° C. for 30 to 60 minutes, and then filter under reduced pressure at 0.05 to 0.095 MPa to obtain a filter cake 1;

[0008] Step 2: Dry the filter cake 1 at 50±5°C for 60-180 min; mix the dried filter cake 1 with 3-6 parts of solvent, and reflux under stirring in a water bath at 60-80°C for 60±5 min;

[0009] Step 3: cooling the mixed solution after refluxing in step 2 to 20±5°C while stirring, and then maintaining the temperature for 60±5min for recrystallization, and filtering under reduced pressure at 0.05-0.095mpa to obtain filter cake 2;

[0010] Step 4: Dry the filter cake 2 at 50±5° C. for 60 to 180 min to obtain refined 3-phenoxypropane-1,2-diol.

[0011] Furthermore, during the reduced pressure filtration in step 1, 1 to 2 portions of 50±5° C. deionized water are used for elution for 5 to 30 minutes.

[0012] Furthermore, the stirring speed in step 1 and step 2 is 150±10 r / min.

[0013] Furthermore, the stirring speed during the cooling of the mixed solution after reflux in step 3 and the recrystallization process is 30-90 r / min.

[0014] Furthermore, during the reduced pressure filtration in step 3, 1 to 3 parts of solvent are used for elution for 5 to 30 minutes.

[0015] Furthermore, the solvent used in step 2 and the solvent used in the process of reduced pressure filtration in step 3 include but are not limited to a mixture of ether and anhydrous ethanol, a mixture of cyclohexane and anhydrous ethanol, or a mixture of anhydrous ethanol and deionized water; the volume ratio of the ether to anhydrous ethanol is 1:(2-10); the volume ratio of the cyclohexane to anhydrous ethanol is 1:(1-10); the volume ratio of the anhydrous ethanol to deionized water is 1:(1-8); the ether, anhydrous ethanol and cyclohexane are all analytically pure.

[0016] The beneficial effects of the present invention are:

[0017] The existing crude phenoxypropane-1,2-diol is usually prepared by using phenol as a raw material, so the obtained crude phenoxypropane-1,2-diol often contains trace amounts of phenol and other impurities. According to the differences in the properties of the product itself, the raw materials and the impurities, the crude 3-phenoxypropane-1,2-diol is dissolved, filtered under reduced pressure, rinsed, refluxed in a water bath, recrystallized and dried, and a series of operation treatments are performed, and the entire process conditions are optimized, so that the purity of the refined 3-phenoxypropane-1,2-diol product can reach 99.9%, no phenol is detected, the content of unknown impurities is less than 0.1%, and the loss rate of the product is not higher than 4%. The overall process of the invention is simple, the cost is low, and the prepared product has high purity and low loss rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a refining process flow chart of the present invention.

[0019] Figure 2 It is the gas chromatogram of the crude product of 3-phenoxypropane-1,2-diol of the present invention.

[0020] Figure 3This is a gas chromatogram of the refined 3-phenoxypropane-1,2-diol prepared in Example 2 of the present invention. DETAILED DESCRIPTION

[0021] The following will be combined with the accompanying drawings in the present invention and accompanied by text descriptions to clearly and completely explain the methods, processes and effects in the embodiments of the present invention.

[0022] Example 1

[0023] See also Figure 1 , a refining process for 3-phenoxypropane-1,2-diol, specifically comprising the following steps:

[0024] Step 1: Mix 1 part of crude 3-phenoxypropane-1,2-diol and 3 parts of deionized water by weight, heat and stir at 50° C. for 30 min, and then filter under reduced pressure at 0.095 MPa to obtain filter cake 1;

[0025] During the reduced pressure filtration in step 1, 1 portion of 50°C deionized water was used for elution for 5 minutes;

[0026] The stirring speed in step 1 is 150 r / min;

[0027] Step 2: Dry the filter cake 1 at 50°C for 60 minutes; mix the dried filter cake 1 with 3 parts of solvent, and stir and reflux in a 60°C water bath for 60 minutes;

[0028] The solvent used in step 2 is a mixture of diethyl ether and anhydrous ethanol; the volume ratio of diethyl ether to anhydrous ethanol is 1:2; the diethyl ether and anhydrous ethanol are both analytical grade;

[0029] The stirring speed in step 2 is 150 r / min;

[0030] Step 3: The mixed solution after refluxing in step 2 was cooled down to 20° C. under stirring, and then kept at the constant temperature for 60 min for recrystallization, and filtered under reduced pressure at 0.095 MPa to obtain filter cake 2;

[0031] The stirring speed during the cooling of the mixed solution after reflux and recrystallization in step 3 is 30 r / min;

[0032] During the reduced pressure filtration in step 3, 2 portions of solvent are used for elution for 15 minutes;

[0033] The solvent used in the process of vacuum filtration in step 3 is a mixture of diethyl ether and anhydrous ethanol; the volume ratio of diethyl ether to anhydrous ethanol is 1:2; the diethyl ether and anhydrous ethanol are both analytically pure;

[0034] The stirring speed in step 3 is significantly lower than that in step 2, mainly to reasonably control the cooling rate of the mixed solution so that it is not higher than 0.5°C / min, thereby facilitating the precipitation of high-purity crystals during the recrystallization process; if the cooling rate is too fast, the crystal precipitation rate will accelerate, the solution will quickly reach supersaturation, the formed crystals will be very fine, the specific surface area will increase, and more impurities will be adsorbed, resulting in reduced product purity;

[0035] Step 4: Dry the filter cake 2 at 50° C. for 60 min to obtain refined 3-phenoxypropane-1,2-diol.

[0036] Example 2

[0037] A refining process for 3-phenoxypropane-1,2-diol specifically comprises the following steps:

[0038] Step 1: Mix 1 part of crude 3-phenoxypropane-1,2-diol and 4 parts of deionized water by weight, heat and stir at 48° C. for 35 minutes, and then filter under reduced pressure at 0.08 MPa to obtain filter cake 1;

[0039] During the reduced pressure filtration in step 1, 2 portions of 45° C. deionized water were used for elution for 15 minutes;

[0040] The stirring speed in step 1 is 155 r / min;

[0041] Step 2: Dry the filter cake 1 at 45°C for 120 min; mix the dried filter cake 1 with 4 parts of solvent, and reflux in a water bath at 75°C with stirring for 62 min;

[0042] The solvent used in step 2 is a mixture of diethyl ether and anhydrous ethanol; the volume ratio of diethyl ether to anhydrous ethanol is 1:5; the diethyl ether and anhydrous ethanol are both analytical grade;

[0043] The stirring speed in step 2 is 155 r / min;

[0044] Step 3: The mixed solution after refluxing in step 2 was cooled down to 15° C. under stirring, and then recrystallized at the constant temperature for 65 min, and filtered under reduced pressure at 0.08 MPa to obtain filter cake 2;

[0045] The stirring speed during the cooling of the mixed solution after reflux in step 3 and the recrystallization process is 60 r / min;

[0046] During the reduced pressure filtration in step 3, 1 part of the solvent is used for elution for 5 minutes;

[0047] The solvent used in the process of vacuum filtration in step 3 is a mixture of diethyl ether and anhydrous ethanol; the volume ratio of diethyl ether to anhydrous ethanol is 1:5; the diethyl ether and anhydrous ethanol are both analytically pure;

[0048] Step 4: Dry the filter cake 2 at 45° C. for 120 min to obtain refined 3-phenoxypropane-1,2-diol.

[0049] Example 3

[0050] A refining process for 3-phenoxypropane-1,2-diol specifically comprises the following steps:

[0051] Step 1: Mix 1 part of crude 3-phenoxypropane-1,2-diol and 5 parts of deionized water by weight, heat and stir at 45° C. for 40 minutes, and then filter under reduced pressure at 0.07 MPa to obtain filter cake 1;

[0052] During the reduced pressure filtration in step 1, 1.5 parts of 55°C deionized water was used for elution for 25 minutes;

[0053] The stirring speed in step 1 is 160 r / min;

[0054] Step 2: Dry the filter cake 1 at 55°C for 120 min; mix the dried filter cake 1 with 5 parts of solvent, and reflux in a water bath at 65°C with stirring for 65 min;

[0055] The solvent used in step 2 is a mixture of diethyl ether and anhydrous ethanol; the volume ratio of diethyl ether to anhydrous ethanol is 1:10; the diethyl ether and anhydrous ethanol are both analytical grade;

[0056] The stirring speed in step 2 is 160r / min;

[0057] Step 3: The mixed solution after refluxing in step 2 was cooled down to 18° C. under stirring, and then recrystallized at the constant temperature for 55 min, and filtered under reduced pressure at 0.07 MPa to obtain filter cake 2;

[0058] The stirring speed during the cooling of the mixed solution after reflux and recrystallization in step 3 is 90 r / min;

[0059] During the reduced pressure filtration in step 3, 3 portions of solvent are used for elution for 30 minutes;

[0060] The solvent used in the process of vacuum filtration in step 3 is a mixture of diethyl ether and anhydrous ethanol; the volume ratio of diethyl ether to anhydrous ethanol is 1:10; the diethyl ether and anhydrous ethanol are both analytically pure;

[0061] Step 4: Dry the filter cake 2 at 55° C. for 120 min to obtain refined 3-phenoxypropane-1,2-diol.

[0062] Example 4

[0063] A refining process for 3-phenoxypropane-1,2-diol specifically comprises the following steps:

[0064] Step 1: Mix 1 part of crude 3-phenoxypropane-1,2-diol and 6 parts of deionized water by weight, heat and stir at 52° C. for 45 minutes, and then filter under reduced pressure at 0.06 MPa to obtain filter cake 1;

[0065] During the reduced pressure filtration in step 1, one portion of 53°C deionized water was used for elution for 30 minutes;

[0066] The stirring speed in step 1 is 145 r / min;

[0067] Step 2: Dry the filter cake 1 at 50°C for 120 min; mix the dried filter cake 1 with 6 parts of solvent, and reflux in a water bath at 79°C with stirring for 55 min;

[0068] The solvent used in step 2 is a mixture of cyclohexane and anhydrous ethanol; the volume ratio of cyclohexane to anhydrous ethanol is 1:1; the cyclohexane and anhydrous ethanol are both analytically pure;

[0069] The stirring speed in step 2 is 145 r / min;

[0070] Step 3: The mixed solution after refluxing in step 2 was cooled down to 22° C. under stirring, and then recrystallized at the constant temperature for 58 min, and filtered under reduced pressure at 0.06 MPa to obtain filter cake 2;

[0071] The stirring speed during the cooling of the mixed solution after reflux in step 3 and the recrystallization process is 50 r / min;

[0072] During the reduced pressure filtration in step 3, 3 portions of solvent are used for elution for 30 minutes;

[0073] The solvent used in the process of vacuum filtration in step 3 is a mixture of cyclohexane and anhydrous ethanol; the volume ratio of cyclohexane to anhydrous ethanol is 1:1; the cyclohexane and anhydrous ethanol are both analytically pure;

[0074] Step 4: Dry the filter cake 2 at 50° C. for 120 min to obtain refined 3-phenoxypropane-1,2-diol.

[0075] Example 5

[0076] A refining process for 3-phenoxypropane-1,2-diol specifically comprises the following steps:

[0077] Step 1: Mix 1 part of crude 3-phenoxypropane-1,2-diol and 7 parts of deionized water by weight, heat and stir at 54° C. for 50 min, and then filter under reduced pressure at 0.05 MPa to obtain filter cake 1;

[0078] During the reduced pressure filtration in step 1, 2 portions of 48° C. deionized water were used for elution for 20 minutes;

[0079] The stirring speed in step 1 is 140 r / min;

[0080] Step 2: Dry the filter cake 1 at 55°C for 180 min; mix the dried filter cake 1 with 5 parts of solvent, and reflux in a water bath at 79°C with stirring for 65 min;

[0081] The solvent used in step 2 is a mixture of cyclohexane and anhydrous ethanol; the volume ratio of cyclohexane to anhydrous ethanol is 1:5; the cyclohexane and anhydrous ethanol are both analytical grade;

[0082] The stirring speed in step 2 is 140 r / min;

[0083] Step 3: The mixed solution after refluxing in step 2 was cooled down to 25° C. under stirring, and then recrystallized at the constant temperature for 65 min, and filtered under reduced pressure at 0.05 MPa to obtain filter cake 2;

[0084] The stirring speed during the cooling of the mixed solution after reflux in step 3 and the recrystallization process is 70 r / min;

[0085] During the reduced pressure filtration in step 3, 2 portions of solvent are used for elution for 15 minutes;

[0086] The solvent used in the process of vacuum filtration in step 3 is a mixture of cyclohexane and anhydrous ethanol; the volume ratio of cyclohexane to anhydrous ethanol is 1:5; the cyclohexane and anhydrous ethanol are both analytically pure;

[0087] Step 4: Dry the filter cake 2 at 55° C. for 180 min to obtain refined 3-phenoxypropane-1,2-diol.

[0088] Example 6

[0089] A refining process for 3-phenoxypropane-1,2-diol specifically comprises the following steps:

[0090] Step 1: Mix 1 part of crude 3-phenoxypropane-1,2-diol and 8 parts of deionized water by weight, heat at 55° C. and stir for 55 min, and then filter under reduced pressure at 0.06 MPa to obtain filter cake 1;

[0091] During the reduced pressure filtration in step 1, 1.5 parts of 50°C deionized water was used for elution for 15 minutes;

[0092] The stirring speed in step 1 is 150 r / min;

[0093] Step 2: Dry the filter cake 1 at 50°C for 180 min; mix the dried filter cake 1 with 4 parts of solvent, and reflux in a water bath at 79°C with stirring for 55 min;

[0094] The solvent used in step 2 is a mixture of cyclohexane and anhydrous ethanol; the volume ratio of cyclohexane to anhydrous ethanol is 1:10; the cyclohexane and anhydrous ethanol are both analytically pure;

[0095] The stirring speed in step 2 is 150 r / min;

[0096] Step 3: cooling the mixed solution after refluxing in step 2 to 20° C. under stirring, and then maintaining the temperature for 60 min for recrystallization, and filtering under reduced pressure at 0.06 MPa to obtain filter cake 2;

[0097] The stirring speed during the cooling of the mixed solution after reflux in step 3 and the recrystallization process is 60 r / min;

[0098] During the reduced pressure filtration in step 3, 1 part of the solvent is used for elution for 5 minutes;

[0099] The solvent used in the process of vacuum filtration in step 3 is a mixture of cyclohexane and anhydrous ethanol; the volume ratio of cyclohexane to anhydrous ethanol is 1:10; the cyclohexane and anhydrous ethanol are both analytically pure;

[0100] Step 4: Dry the filter cake 2 at 50° C. for 180 min to obtain refined 3-phenoxypropane-1,2-diol.

[0101] Example 7

[0102] A refining process for 3-phenoxypropane-1,2-diol specifically comprises the following steps:

[0103] Step 1: Mix 1 part of crude 3-phenoxypropane-1,2-diol and 6 parts of deionized water by weight, heat and stir at 53° C. for 60 min, and then filter under reduced pressure at 0.07 MPa to obtain filter cake 1;

[0104] During the reduced pressure filtration in step 1, 1 portion of 45°C deionized water was used for 30 minutes;

[0105] The stirring speed in step 1 is 155 r / min;

[0106] Step 2: Dry the filter cake 1 at 50°C for 120 min; mix the dried filter cake 1 with 3 parts of solvent, and reflux in a water bath at 80°C with stirring for 55 min;

[0107] The solvent used in step 2 is a mixture of anhydrous ethanol and deionized water; the volume ratio of anhydrous ethanol to deionized water is 1:1; the anhydrous ethanol is analytical grade;

[0108] The stirring speed in step 2 is 155 r / min;

[0109] Step 3: The mixed solution after refluxing in step 2 was cooled down to 18° C. under stirring, and then recrystallized at the constant temperature for 55 min, and filtered under reduced pressure at 0.07 MPa to obtain filter cake 2;

[0110] The stirring speed during the cooling of the mixed solution after reflux in step 3 and the recrystallization process is 60r / min;

[0111] During the reduced pressure filtration in step 3, 2 portions of solvent are used for elution for 15 minutes;

[0112] The solvent used in the process of vacuum filtration in step 3 is a mixture of anhydrous ethanol and deionized water; the volume ratio of anhydrous ethanol to deionized water is 1:1; the anhydrous ethanol is analytical grade;

[0113] Step 4: Dry the filter cake 2 at 50° C. for 120 min to obtain refined 3-phenoxypropane-1,2-diol.

[0114] Example 8

[0115] A refining process for 3-phenoxypropane-1,2-diol specifically comprises the following steps:

[0116] Step 1: Mix 1 part of crude 3-phenoxypropane-1,2-diol and 5 parts of deionized water by weight, heat and stir at 50° C. for 45 minutes, and then filter under reduced pressure at 0.08 MPa to obtain filter cake 1;

[0117] During the reduced pressure filtration in step 1, 2 portions of 48° C. deionized water were used for elution for 25 minutes;

[0118] The stirring speed in step 1 is 150 r / min;

[0119] Step 2: Dry the filter cake 1 at 55°C for 120 min; mix the dried filter cake 1 with 6 parts of solvent, and stir and reflux in a water bath at 80°C for 60 min;

[0120] The solvent used in step 2 is a mixture of anhydrous ethanol and deionized water; the volume ratio of anhydrous ethanol to deionized water is 1:5; the anhydrous ethanol is analytical grade;

[0121] The stirring speed in step 2 is 150 r / min;

[0122] Step 3: The mixed solution after refluxing in step 2 was cooled down to 22° C. under stirring, and then recrystallized at the constant temperature for 62 min, and filtered under reduced pressure at 0.08 MPa to obtain filter cake 2;

[0123] The stirring speed during the cooling of the mixed solution after reflux in step 3 and the recrystallization process is 50 r / min;

[0124] During the reduced pressure filtration in step 3, 1 part of the solvent is used for elution for 5 minutes;

[0125] The solvent used in the process of vacuum filtration in step 3 is a mixture of anhydrous ethanol and deionized water; the volume ratio of anhydrous ethanol to deionized water is 1:5; the anhydrous ethanol is analytical grade;

[0126] Step 4: Dry the filter cake 2 at 55° C. for 120 min to obtain refined 3-phenoxypropane-1,2-diol.

[0127] Example 9

[0128] A refining process for 3-phenoxypropane-1,2-diol specifically comprises the following steps:

[0129] Step 1: Mix 1 part of crude 3-phenoxypropane-1,2-diol and 3 parts of deionized water by weight, heat at 50° C. and stir for 60 min, and then filter under reduced pressure at 0.095 MPa to obtain filter cake 1;

[0130] During the reduced pressure filtration in step 1, 1 portion of 50°C deionized water was used for elution for 5 minutes;

[0131] The stirring speed in step 1 is 160 r / min;

[0132] Step 2: Dry the filter cake 1 at 55°C for 60 minutes; mix the dried filter cake 1 with 5 parts of solvent, and stir and reflux in a water bath at 80°C for 60 minutes;

[0133] The solvent used in step 2 is a mixture of anhydrous ethanol and deionized water; the volume ratio of anhydrous ethanol to deionized water is 1:8; the anhydrous ethanol is analytical grade;

[0134] The stirring speed in step 2 is 160r / min;

[0135] Step 3: The mixed solution after refluxing in step 2 was cooled down to 18° C. under stirring, and then recrystallized at the constant temperature for 55 min, and filtered under reduced pressure at 0.095 MPa to obtain filter cake 2;

[0136] The stirring speed during the cooling of the mixed solution after reflux in step 3 and the recrystallization process is 40 r / min;

[0137] During the reduced pressure filtration in step 3, 3 portions of solvent are used for elution for 30 minutes;

[0138] The solvent used in the process of vacuum filtration in step 3 is a mixture of anhydrous ethanol and deionized water; the volume ratio of anhydrous ethanol to deionized water is 1:8; the anhydrous ethanol is analytical grade;

[0139] Step 4: Dry the filter cake 2 at 55° C. for 60 min to obtain refined 3-phenoxypropane-1,2-diol.

[0140] The solvent used in step 2 of this embodiment and the solvent used in the process of vacuum filtration in step 3 include, but are not limited to, a mixture of ether and anhydrous ethanol, a mixture of cyclohexane and anhydrous ethanol, or a mixture of anhydrous ethanol and deionized water.

[0141] A mixture of ether and methanol (the volume ratio of ether to methanol is 1:3-10), a mixture of methanol and ethanol (the volume ratio of methanol to ethanol is 1:1-10), a mixture of methanol and deionized water (the volume ratio of methanol to deionized water is 1:1-9), etc. can be used as the solvent used in step 2 of this embodiment and the solvent used in the process of reduced pressure filtration in step 3.

[0142] Test verification

[0143] After the purification was completed, the purified 3-phenoxypropane-1,2-diol and the crude 3-phenoxypropane-1,2-diol obtained in each of the above examples were analyzed by gas chromatography.

[0144] like Figure 2 As shown, by gas chromatography analysis of the crude 3-phenoxypropane-1,2-diol, it can be obtained that the crude 3-phenoxypropane-1,2-diol is mainly composed of 6 components, among which the retention time of 3-phenoxypropane-1,2-diol is 13.15min, the retention time of phenol is 10.32min, and the retention times of other impurities 1-4 with higher contents are 8.91min, 11.91min, 20.13min, and 22.73min, respectively. The purity of 3-phenoxypropane-1,2-diol calculated by the area normalization method is 85.65%, the phenol content is 1.50%, and the total content of other unknown impurities is 12.85%.

[0145] like Figure 3As shown, by performing gas chromatography analysis on the refined 3-phenoxypropane-1,2-diol prepared in Example 2, it can be obtained that the retention time of 3-phenoxypropane-1,2-diol in the refined product is 13.18 min, which is consistent with the crude product, and there is no peak at a retention time of about 10.32 min, indicating that there is no phenol in the refined product. Except for the solvent peak, other impurity peaks in the crude product do not appear. The purity of 3-phenoxypropane-1,2-diol calculated by the area normalization method is 99.99%.

[0146] pass Figure 2 and Figure 3 The comparison shows that the refining process of the present invention can obtain high-purity 3-phenoxypropane-1,2-diol. The purity of the refined 3-phenoxypropane-1,2-diol is greater than 99.9%, no phenol is detected, and the impurity content is less than 0.1%.

[0147] The above operation was repeated to analyze the refined 3-phenoxypropane-1,2-diol prepared in Example 1 and Examples 3-9 by gas chromatography; the purity was calculated by area normalization method based on the peak area of ​​the gas chromatogram of each example. The results are shown in Table 1:

[0148] Table 1 Comparison of purity, phenol content and impurity components of crude and refined 3-phenoxypropane-1,2-diol

[0149]

[0150] It can be seen from Table 1 that the 3-phenoxypropane-1,2-diol content in the crude product is 85.65%, the phenol content is 1.50%, and the content of other unknown impurities is 12.85%; the 3-phenoxypropane-1,2-diol obtained after treatment by the process of the present invention has a purity greater than 99.9%, a phenol content of 0, and the content of other unknown impurities is less than 0.1%.

[0151] In addition, by weight analysis of the crude 3-phenoxypropane-1,2-diol and the refined 3-phenoxypropane-1,2-diol before and after purification, it was found that the product loss rate was no more than 4%.

[0152] The above description is only by way of illustration of certain exemplary embodiments of the present invention. It is undoubted that those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the above drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A process for refining 3-phenoxypropane-1,2-diol, characterized in that: The specific steps include: Step 1: Mix 1 part of crude 3-phenoxypropane-1,2-diol and 3 to 8 parts of deionized water by weight, heat and stir at 50±5° C. for 30 to 60 minutes, and then filter under reduced pressure at 0.05 to 0.095 MPa to obtain a filter cake 1; Step 2: Dry the filter cake 1 at 50±5°C for 60-180 min; mix the dried filter cake 1 with 3-6 parts of solvent, and reflux under stirring in a water bath at 60-80°C for 60±5 min; Step 3: cooling the mixed solution after refluxing in step 2 to 20±5°C while stirring, and then maintaining the temperature for 60±5min for recrystallization, and filtering under reduced pressure at 0.05-0.095mpa to obtain filter cake 2; Step 4: Dry the filter cake 2 at 50±5° C. for 60 to 180 min to obtain refined 3-phenoxypropane-1,2-diol.

2. A process for refining 3-phenoxypropane-1,2-diol according to claim 1, characterized in that: During the reduced pressure filtration in step 1, 1 to 2 portions of 50±5° C. deionized water are used for elution for 5 to 30 minutes.

3. A process for refining 3-phenoxypropane-1,2-diol according to claim 1, characterized in that: The stirring speed in step 1 and step 2 is 150±10 r / min.

4. A process for refining 3-phenoxypropane-1,2-diol according to claim 1, characterized in that: The stirring speed during the cooling of the mixed solution after reflux and the recrystallization process in step 3 is 30-90 r / min.

5. A process for refining 3-phenoxypropane-1,2-diol according to claim 1, characterized in that: During the reduced pressure filtration in step 3, 1 to 3 portions of solvent are used for elution for 5 to 30 minutes.

6. A process for refining 3-phenoxypropane-1,2-diol according to claim 1 or 5, characterized in that: The solvent used in step 2 and the solvent used in the process of reduced pressure filtration in step 3 include but are not limited to a mixture of ether and anhydrous ethanol, a mixture of cyclohexane and anhydrous ethanol, or a mixture of anhydrous ethanol and deionized water; the volume ratio of the ether to anhydrous ethanol is 1:(2-10); the volume ratio of the cyclohexane to anhydrous ethanol is 1:(1-10); the volume ratio of the anhydrous ethanol to deionized water is 1:(1-8); the ether, anhydrous ethanol and cyclohexane are all analytically pure.

7. A process for refining 3-phenoxypropane-1,2-diol, characterized in that: The specific steps include: Step 1: Mix 1 part of crude 3-phenoxypropane-1,2-diol and 3 parts of deionized water by weight, heat and stir at 50° C. for 30 min, and then filter under reduced pressure at 0.095 MPa to obtain filter cake 1; During the reduced pressure filtration in step 1, 1 portion of 50°C deionized water was used for elution for 5 minutes; The stirring speed in step 1 is 150 r / min; Step 2: Dry the filter cake 1 at 50°C for 60 minutes; mix the dried filter cake 1 with 3 parts of solvent, and stir and reflux in a 60°C water bath for 60 minutes; The solvent used in step 2 is a mixture of diethyl ether and anhydrous ethanol; the volume ratio of diethyl ether to anhydrous ethanol is 1:2; the diethyl ether and anhydrous ethanol are both analytical grade; The stirring speed in step 2 is 150 r / min; Step 3: The mixed solution after refluxing in step 2 was cooled down to 20° C. under stirring, and then recrystallized at the constant temperature for 60 min, and filtered under reduced pressure at 0.095 MPa to obtain filter cake 2; The stirring speed during the cooling of the mixed solution after reflux in step 3 and the recrystallization process is 30 r / min; During the reduced pressure filtration in step 3, 2 portions of solvent are used for elution for 15 minutes; The solvent used in the process of vacuum filtration in step 3 is a mixture of diethyl ether and anhydrous ethanol; the volume ratio of diethyl ether to anhydrous ethanol is 1:2; the diethyl ether and anhydrous ethanol are both analytically pure; Step 4: Dry the filter cake 2 at 50° C. for 60 min to obtain refined 3-phenoxypropane-1,2-diol.

8. A process for refining 3-phenoxypropane-1,2-diol, characterized in that: The specific steps include: Step 1: Mix 1 part of crude 3-phenoxypropane-1,2-diol and 4 parts of deionized water by weight, heat and stir at 48° C. for 35 minutes, and then filter under reduced pressure at 0.08 MPa to obtain filter cake 1; During the reduced pressure filtration in step 1, 2 portions of 45° C. deionized water were used for elution for 15 minutes; The stirring speed in step 1 is 155 r / min; Step 2: Dry the filter cake 1 at 45°C for 120 min; mix the dried filter cake 1 with 4 parts of solvent, and reflux in a water bath at 75°C with stirring for 62 min; The solvent used in step 2 is a mixture of diethyl ether and anhydrous ethanol; the volume ratio of diethyl ether to anhydrous ethanol is 1:5; the diethyl ether and anhydrous ethanol are both analytical grade; The stirring speed in step 2 is 155 r / min; Step 3: The mixed solution after refluxing in step 2 was cooled down to 15° C. under stirring, and then recrystallized at the constant temperature for 65 min, and filtered under reduced pressure at 0.08 MPa to obtain filter cake 2; The stirring speed during the cooling of the mixed solution after reflux in step 3 and the recrystallization process is 60r / min; During the reduced pressure filtration in step 3, 1 part of the solvent is used for elution for 5 minutes; The solvent used in the process of vacuum filtration in step 3 is a mixture of diethyl ether and anhydrous ethanol; the volume ratio of diethyl ether to anhydrous ethanol is 1:5; the diethyl ether and anhydrous ethanol are both analytically pure; Step 4: Dry the filter cake 2 at 45° C. for 120 min to obtain refined 3-phenoxypropane-1,2-diol.

9. A process for refining 3-phenoxypropane-1,2-diol, characterized in that: The specific steps include: Step 1: Mix 1 part of crude 3-phenoxypropane-1,2-diol and 6 parts of deionized water by weight, heat and stir at 52° C. for 45 minutes, and then filter under reduced pressure at 0.06 MPa to obtain filter cake 1; During the reduced pressure filtration in step 1, 1 portion of 53°C deionized water was used for 30 minutes; The stirring speed in step 1 is 145 r / min; Step 2: Dry the filter cake 1 at 50°C for 120 min; mix the dried filter cake 1 with 6 parts of solvent, and reflux in a water bath at 79°C with stirring for 55 min; The solvent used in step 2 is a mixture of cyclohexane and anhydrous ethanol; the volume ratio of cyclohexane to anhydrous ethanol is 1:1; the cyclohexane and anhydrous ethanol are both analytically pure; The stirring speed in step 2 is 145 r / min; Step 3: The mixed solution after refluxing in step 2 was cooled down to 22° C. under stirring, and then recrystallized at the constant temperature for 58 min, and filtered under reduced pressure at 0.06 MPa to obtain filter cake 2; The stirring speed during the cooling of the mixed solution after reflux in step 3 and the recrystallization process is 50 r / min; During the reduced pressure filtration in step 3, 3 portions of solvent are used for elution for 30 minutes; The solvent used in the process of vacuum filtration in step 3 is a mixture of cyclohexane and anhydrous ethanol; the volume ratio of cyclohexane to anhydrous ethanol is 1:1; the cyclohexane and anhydrous ethanol are both analytically pure; Step 4: Dry the filter cake 2 at 50° C. for 120 min to obtain refined 3-phenoxypropane-1,2-diol.

10. A process for refining 3-phenoxypropane-1,2-diol, characterized in that: The specific steps include: Step 1: Mix 1 part of crude 3-phenoxypropane-1,2-diol and 3 parts of deionized water by weight, heat at 50° C. and stir for 60 min, and then filter under reduced pressure at 0.095 MPa to obtain filter cake 1; During the reduced pressure filtration in step 1, 1 portion of 50°C deionized water was used for elution for 5 minutes; The stirring speed in step 1 is 160 r / min; Step 2: Dry the filter cake 1 at 55°C for 60 minutes; mix the dried filter cake 1 with 5 parts of solvent, and stir and reflux in a water bath at 80°C for 60 minutes; The solvent used in step 2 is a mixture of anhydrous ethanol and deionized water; the volume ratio of anhydrous ethanol to deionized water is 1:8; the anhydrous ethanol is analytical grade; The stirring speed in step 2 is 160r / min; Step 3: The mixed solution after refluxing in step 2 was cooled down to 18° C. under stirring, and then recrystallized at the constant temperature for 55 min, and filtered under reduced pressure at 0.095 MPa to obtain filter cake 2; The stirring speed during the cooling of the mixed solution after reflux in step 3 and the recrystallization process is 40 r / min; During the reduced pressure filtration in step 3, 3 portions of solvent are used for elution for 30 minutes; The solvent used in the process of vacuum filtration in step 3 is a mixture of anhydrous ethanol and deionized water; the volume ratio of anhydrous ethanol to deionized water is 1:8; the anhydrous ethanol is analytical grade; Step 4: Dry the filter cake 2 at 55° C. for 60 min to obtain refined 3-phenoxypropane-1,2-diol.

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