Method for recovering thiamine hydrochloride from thiamine hydrochloride mother liquor and application thereof
By evaporating and freezing methanol in thiamine hydrochloride mother liquor, the problem of thiamine hydrochloride cannot be recovered in the prior art is solved, efficient utilization of resources and reduction of production costs, and environmentally friendly treatment pressure is reduced.
Patent Information
- Application Number
- CN202411770640.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-04
- Publication Date
- 2025-03-11
AI Technical Summary
The prior art cannot effectively recover thiamine hydrochloride in the mother liquor of thiamine hydrochloride, resulting in waste of resources, and after neutralization, thiamine hydrochloride is destroyed, becoming the main source of distillation, high boiling and high COD, and the environmental protection treatment pressure is high.
Thiamine hydrochloride was recovered by evaporating the mother liquor of thiamine hydrochloride and freezing. The specific steps include atmospheric distillation within the range of 45%-65% methanol evaporation, then freezing the evaporated residue below -5°C, and solid-liquid separation to recover thiamine hydrochloride.
It realizes efficient recycling of thiamine hydrochloride, maximizes the utilization of resources in the mother liquor, reduces production costs, and avoids the generation of high COD and high ammonia nitrogen wastewater, reducing environmental protection treatment pressure.
Smart Images
Figure CN119591592A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of mother liquor recovery, and in particular to a method for recovering thiamine hydrochloride from thiamine hydrochloride mother liquor and application thereof. Background Art
[0002] Thiamine hydrochloride is usually produced by a hydrogen chloride generation process, and the resulting mother liquor contains about 1% of thiamine hydrochloride. The conventional treatment process of the mother liquor is to use liquid alkali to directly neutralize it to neutrality and then separate and remove salt. After centrifuging the mother liquor, it is distilled in a distillation tower and the distilled methanol is recycled. However, this treatment process cannot recover the thiamine hydrochloride in the mother liquor, resulting in a waste of resources. In addition, the thiamine hydrochloride in the mother liquor after neutralization is destroyed, becoming the main source of high boiling point and high COD in distillation, and the pressure of environmental protection treatment is high.
[0003] In view of this, the present invention is proposed. Summary of the invention
[0004] One of the purposes of the present invention is to provide a method for recovering thiamine hydrochloride from thiamine hydrochloride mother liquor, which can comprehensively utilize the effective materials in the thiamine hydrochloride mother liquor and maximize the recovery of thiamine hydrochloride in the mother liquor.
[0005] The second object of the present invention is to provide an application of a method for recovering thiamine hydrochloride from thiamine hydrochloride mother liquor, which is beneficial to reducing production costs and solving the problem of high COD and high ammonia nitrogen wastewater generated when treating thiamine hydrochloride mother liquor.
[0006] In order to achieve the above-mentioned purpose of the present invention, the following technical solutions are particularly adopted:
[0007] In a first aspect, a method for recovering thiamine hydrochloride from a thiamine hydrochloride mother liquor comprises the following steps:
[0008] The thiamine hydrochloride mother liquor is evaporated of methanol and then subjected to freezing treatment to recover thiamine hydrochloride;
[0009] The evaporation amount of the methanol is between 45% and 65%.
[0010] Furthermore, the evaporation amount of the methanol is between 50% and 60%.
[0011] Furthermore, the evaporation method includes atmospheric distillation.
[0012] Furthermore, the mass content of thiamine hydrochloride in the thiamine hydrochloride mother solution is 0.8%-1.2%.
[0013] Furthermore, the temperature of the freezing treatment is below -5°C.
[0014] Furthermore, after the freezing treatment, the method further comprises a step of solid-liquid separation of the obtained frozen mixture.
[0015] Furthermore, the solid-liquid separation method includes filtration.
[0016] Furthermore, the recovery rate of thiamine hydrochloride is above 60%.
[0017] Furthermore, the recovery rate of thiamine hydrochloride is between 60% and 90%.
[0018] In a second aspect, a method as described above is used in the synthesis of thiamine hydrochloride.
[0019] Compared with the prior art, the present invention has at least the following beneficial effects:
[0020] The method for recovering thiamine hydrochloride from thiamine hydrochloride mother liquor provided by the present invention comprises the following steps: firstly evaporating a specific amount of methanol from the mother liquor, and then freezing the evaporation residual liquid, so that thiamine hydrochloride can be effectively precipitated and thiamine hydrochloride contained in the mother liquor is recovered to the maximum extent, so that resources are effectively utilized, the problem of high COD and high ammonia nitrogen wastewater generated during the treatment of the thiamine hydrochloride mother liquor is avoided, and the production cost and the difficulty of the mother liquor treatment are reduced.
[0021] The application of the method for recovering thiamine hydrochloride from thiamine hydrochloride mother liquor provided by the present invention is beneficial to reducing production costs and solves the problem of generating high COD and high ammonia nitrogen wastewater when treating thiamine hydrochloride mother liquor. BRIEF DESCRIPTION OF THE DRAWINGS
[0022] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.
[0023] Figure 1 A process flow chart for recovering thiamine hydrochloride from thiamine hydrochloride mother liquor is provided in one embodiment of the present invention. DETAILED DESCRIPTION
[0024] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0025] According to a first aspect of the present invention, there is provided a method for recovering thiamine hydrochloride from thiamine hydrochloride mother liquor, comprising the following steps:
[0026] The thiamine hydrochloride mother liquor is evaporated of methanol and then subjected to freezing treatment to recover thiamine hydrochloride;
[0027] The evaporation amount of methanol is between 45% and 65%, for example, 45%, 50%, 55%, 60%, or 65%, but not limited thereto.
[0028] The method for recovering thiamine hydrochloride from thiamine hydrochloride mother liquor provided by the present invention comprises the following steps: firstly evaporating a specific amount of methanol from the mother liquor, and then freezing the evaporation residual liquid, so that thiamine hydrochloride can be effectively precipitated and thiamine hydrochloride contained in the mother liquor is recovered to the maximum extent, so that resources are effectively utilized, the problem of high COD and high ammonia nitrogen wastewater generated during the treatment of the thiamine hydrochloride mother liquor is avoided, and the production cost and the difficulty of the mother liquor treatment are reduced.
[0029] In the present invention, the mass content of thiamine hydrochloride in the thiamine hydrochloride mother solution may be 0.8%-1.2%, for example, 0.8%, 0.9%, 1%, 1.1%, 1.2%, but not limited thereto.
[0030] In a preferred embodiment, the evaporation amount of methanol can be between 50% and 60%. An appropriate evaporation amount of methanol is more conducive to further improving the recovery rate of thiamine hydrochloride. If the evaporation amount of methanol is too low or too high, a high recovery rate of thiamine hydrochloride cannot be guaranteed.
[0031] In a preferred embodiment, the evaporation method includes but is not limited to atmospheric distillation.
[0032] In the present invention, a rotary evaporator can be used for atmospheric distillation, so that a part of the methanol can be directly recovered, and the mother liquor after distillation is then frozen to recover the thiamine hydrochloride therein. It can be seen that the recovery method is simple, efficient and easy to operate.
[0033] In a preferred embodiment, the temperature of the freezing treatment may be below -5°C, for example, -5°C, -6°C, -7°C, -8°C, -9°C, -10°C, but not limited thereto, which is more conducive to further improving the recovery rate of thiamine hydrochloride.
[0034] In a preferred embodiment, the freezing treatment further includes but is not limited to the step of performing solid-liquid separation on the obtained frozen mixture.
[0035] The solid-liquid separation method includes but is not limited to filtration, and the obtained filter cake is thiamine hydrochloride.
[0036] A typical method for recovering thiamine hydrochloride from thiamine hydrochloride mother liquor, the process flow chart is shown in Figure 1 , including the following steps:
[0037] After recovering part of the methanol from the thiamine hydrochloride mother liquor by atmospheric distillation, the obtained distillation residue is frozen to reduce its temperature to below -5°C, kept warm and stirred for at least 2 hours, filtered to obtain a filter cake and a filtrate, and the obtained filter cake is dried to recover a crude thiamine hydrochloride product, wherein the thiamine hydrochloride content in the crude product is above 98%.
[0038] In a preferred embodiment, the recovery rate of thiamine hydrochloride may be above 60%, for example, 60%, 65%, 70%, 75%, 80%, 85%, 90%, but not limited thereto, and may further preferably be 60%-90%.
[0039] In summary, the recovery method of the present invention, with the coordinated cooperation of various steps and process parameters, realizes the comprehensive utilization of effective materials in the thiamine hydrochloride mother liquor, and also maximizes the recovery of thiamine hydrochloride in the mother liquor, which is beneficial to reducing production costs and effectively solves the technical problem of generating high COD and high ammonia nitrogen wastewater during the treatment of thiamine hydrochloride mother liquor in the prior art.
[0040] According to a second aspect of the present invention, there is provided an application of any of the above methods in the synthesis of thiamine hydrochloride.
[0041] The application of the method for recovering thiamine hydrochloride from thiamine hydrochloride mother liquor provided by the present invention is beneficial to reducing production costs and solves the problem of generating high COD and high ammonia nitrogen wastewater when treating thiamine hydrochloride mother liquor.
[0042] The present invention is further described below by way of examples. Unless otherwise specified, the materials in the examples are prepared according to existing methods or directly purchased from the market.
[0043] Example 1
[0044] A method for recovering thiamine hydrochloride from thiamine hydrochloride mother liquor comprises the following steps:
[0045] (a) taking 1000 g of thiamine hydrochloride mother liquor (containing about 1% by weight of thiamine hydrochloride), collecting 446 g of methanol by atmospheric distillation in a water bath at 70° C., with a methanol recovery ratio of 44.6%, as shown in Table 1, and obtaining a distillation residue;
[0046] (b) The distillation residue was subjected to freezing treatment, i.e., it was cooled to below -5°C, then kept warm and stirred for 2 hours, and then filtered to obtain a filter cake of about 1.2 g. After the filter cake was dried, 1.05 g of crude thiamine hydrochloride was recovered. The thiamine hydrochloride content was detected to be 98.88%, and the thiamine hydrochloride recovery rate was 10.5%, as shown in Table 1.
[0047] Example 2
[0048] A method for recovering thiamine hydrochloride from thiamine hydrochloride mother liquor comprises the following steps:
[0049] (a) taking 1000 g of thiamine hydrochloride mother liquor (containing about 1% by weight of thiamine hydrochloride), collecting 498 g of methanol by atmospheric distillation in a water bath at 70° C., with a methanol recovery ratio of 49.8%, as shown in Table 1, and obtaining a distillation residue;
[0050] (b) The distillation residue was subjected to freezing treatment, i.e., it was cooled to below -5°C, then kept warm and stirred for 2 hours, and then filtered to obtain about 6.8 g of filter cake. After drying the filter cake, 6.28 g of crude thiamine hydrochloride was recovered. The thiamine hydrochloride content was detected to be 98.88%, and the thiamine hydrochloride recovery rate was 62.8%, as shown in Table 1.
[0051] Example 3
[0052] A method for recovering thiamine hydrochloride from thiamine hydrochloride mother liquor comprises the following steps:
[0053] (a) taking 1000 g of thiamine hydrochloride mother liquor (containing about 1% by weight of thiamine hydrochloride), collecting 540 g of methanol by atmospheric distillation in a water bath at 70° C., with a methanol recovery ratio of 54.0%, as shown in Table 1, and obtaining a distillation residue;
[0054] (b) The distillation residue was subjected to freezing treatment, i.e., cooled to below -5°C, then kept warm and stirred for 2 h, and then filtered to obtain a filter cake of about 9.8 g. After drying the filter cake, 8.78 g of crude thiamine hydrochloride was recovered. The thiamine hydrochloride content was detected to be 98.72%, and the thiamine hydrochloride recovery rate was 87.8%, as shown in Table 1.
[0055] Example 4
[0056] A method for recovering thiamine hydrochloride from thiamine hydrochloride mother liquor comprises the following steps:
[0057] (a) taking 1000 g of thiamine hydrochloride mother liquor (containing about 1% by weight of thiamine hydrochloride), collecting 598 g of methanol by atmospheric distillation in a water bath at 70° C., with a methanol recovery ratio of 59.8%, as shown in Table 1, and obtaining a distillation residue;
[0058] (b) The distillation residue was subjected to freezing treatment, i.e., it was cooled to below -5°C, then kept warm and stirred for 2 hours, and then filtered to obtain a filter cake of about 7.4 g. After the filter cake was dried, 6.72 g of crude thiamine hydrochloride was recovered. The thiamine hydrochloride content was detected to be 98.95%, and the thiamine hydrochloride recovery rate was 67.2%, as shown in Table 1.
[0059] Example 5
[0060] A method for recovering thiamine hydrochloride from thiamine hydrochloride mother liquor comprises the following steps:
[0061] (a) taking 1000 g of thiamine hydrochloride mother liquor (containing about 1% by weight of thiamine hydrochloride), collecting 642 g of methanol by atmospheric distillation in a water bath at 70° C., with a methanol recovery ratio of 64.2%, as shown in Table 1, and obtaining a distillation residue;
[0062] (b) The distillation residue was subjected to freezing treatment, i.e., it was cooled to below -5°C, then kept warm and stirred for 2 hours, and then filtered to obtain a filter cake of about 1.64 g. After the filter cake was dried, 1.42 g of crude thiamine hydrochloride was recovered. The thiamine hydrochloride content was detected to be 98.64%, and the thiamine hydrochloride recovery rate was 14.2%, as shown in Table 1.
[0063] Comparative Example 1
[0064] A method for recovering thiamine hydrochloride from thiamine hydrochloride mother liquor comprises the following steps:
[0065] (a) taking 1000 g of thiamine hydrochloride mother liquor (containing about 1% by weight of thiamine hydrochloride), collecting 395 g of methanol by atmospheric distillation in a water bath at 70° C., with a methanol recovery ratio of 39.5%, as shown in Table 1, and obtaining a distillation residue;
[0066] (b) The distillation residue was subjected to freezing treatment, i.e., it was cooled to below -5°C and then kept warm and stirred for 2 hours. The solution remained clear without any precipitation. Thiamine hydrochloride could not be recovered and the recovery rate of thiamine hydrochloride was 0. See Table 1.
[0067] Comparative Example 2
[0068] A method for recovering thiamine hydrochloride from thiamine hydrochloride mother liquor comprises the following steps:
[0069] (a) taking 1000 g of thiamine hydrochloride mother liquor (containing about 1% by weight of thiamine hydrochloride), collecting 690 g of methanol by atmospheric distillation in a water bath at 70° C., with a methanol recovery ratio of 69.0%, as shown in Table 1, and obtaining a distillation residue;
[0070] (b) The distillation residue was subjected to freezing treatment, i.e., it was cooled to below -5°C and then kept warm and stirred for 2 hours. The solution remained clear without any precipitation. Thiamine hydrochloride could not be recovered and the recovery rate of thiamine hydrochloride was 0. See Table 1.
[0071] Table 1
[0072]
[0073] It can be seen from the data in Table 1 that when the methanol recovery ratio of the thiamine hydrochloride mother liquor is controlled between 45% and 65%, thiamine hydrochloride can be recovered after freezing. In particular, when the methanol recovery ratio is controlled between 50% and 60%, the recovery rate of thiamine hydrochloride can be further improved, ensuring the highest recovery rate of thiamine hydrochloride.
[0074] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.
Claims
1. A method for recovering thiamine hydrochloride from thiamine hydrochloride mother liquor, characterized in that: The following steps are involved: The thiamine hydrochloride mother liquor is evaporated of methanol and then subjected to freezing treatment to recover thiamine hydrochloride; The evaporation amount of the methanol is between 45% and 65%.
2. The method according to claim 1, characterized in that The evaporation amount of the methanol is between 50% and 60%.
3. The method according to claim 1, characterized in that The evaporation method includes atmospheric distillation.
4. The method according to claim 1, characterized in that: The mass content of thiamine hydrochloride in the thiamine hydrochloride mother solution is 0.8%-1.2%.
5. The method according to any one of claims 1 to 4, characterized in that: The temperature of the freezing treatment is below -5°C.
6. The method according to claim 5, characterized in that The freezing treatment further comprises a step of performing solid-liquid separation on the obtained frozen mixture.
7. The method according to claim 6, characterized in that The solid-liquid separation method includes filtration.
8. The method according to claim 5, characterized in that The recovery rate of thiamine hydrochloride is above 60%.
9. The method according to claim 8, characterized in that The recovery rate of thiamine hydrochloride is between 60% and 90%.
10. Use of the method according to any one of claims 1 to 9 in the synthesis of thiamine hydrochloride.