A preparation method for jointly producing β-menadione and potassium permanganate

Abstract

The invention provides a preparation method for the joint production of β-menadione and potassium permanganate, wherein a crystallization mother liquor obtained in the process of producing potassium permanganate is used as an oxidant in the process of producing β-menadione, thereby reducing the consumption of finished potassium permanganate in the process of producing β-menadione and reducing production costs; meanwhile, the recycling and utilization of resources are realized, waste generated in the process is reduced, and the environment is protected.

Description

Technical Field

[0001] The invention belongs to the technical field of chemical synthesis, and particularly relates to a preparation method for the combined production of beta-menadione and potassium permanganate. Background Art

[0002] The chemical name of β-menadione is 2-methyl-1,4-naphthoquinone. Pure product appears as bright yellow crystals or crystalline powder with a distinctive pungent odor. It is insoluble in water but soluble in ethanol, benzene, chloroform, carbon tetrachloride, and vegetable oils. It is stable in air but easily deteriorates and decomposes in the presence of light, alkali, and reducing agents. It is used as a feed additive, primarily to promote the synthesis of prothrombin in the liver of livestock and poultry and the synthesis of plasma coagulation factors in the liver, acting as a hemostatic agent.

[0003] MSB (sodium menadione bisulfite) is obtained by the addition reaction of β-menadione and sodium bisulfite. MSB is a white crystalline powder that is easily soluble in water and hot ethanol, insoluble in benzene and ether, and has an aqueous solution pH of approximately 4.7-7. It is stable at room temperature but easily decomposes in the presence of light. It can be used to treat bleeding disorders, among other conditions.

[0004] Currently, β-menadione is synthesized by three different methods:

[0005] (1) Sodium dichromate (potassium dichromate) oxidation method

[0006] This method, the most widely used synthesis technique, is the "chromium process," which uses sodium dichromate or potassium dichromate as an oxidant to oxidize β-methylnaphthalene in the presence of sulfuric acid to produce β-menadione in a yield of approximately 51%. The "chromium process" uses highly toxic hexavalent chromium and produces large amounts of chromium-containing wastewater, resulting in severe environmental pollution and significant health hazards to operators.

[0007] (2) Hydrogen peroxide oxidation method

[0008] This method uses hydrogen peroxide (about 30% concentration) as the oxidant, acetic acid as the solvent, and methyl paraformaldehyde or Pd(II) sulfate-polystyrene resin as the catalyst. This method has a high yield, but the amount of hydrogen peroxide used is large, and the catalyst is difficult to recycle and reuse. It also produces a lot of wastewater and causes serious environmental pollution.

[0009] (3) High-valent cerium salt oxidation method

[0010] This method uses Ce under acidic conditions of methanesulfonic acid or sulfuric acid. 4+ Oxidation of β-methylnaphthalene to β-menadione, separation of Ce-containing menadione 3+ The residual oxidation solution is filtered, oxidized to remove organic matter, decolorized and then electrolytically oxidized to obtain Ce again. 4+, thus achieving recycling. However, the addition of emulsifiers during the oxidation process enhances mass transfer and accelerates the reaction rate. However, the emulsifiers cannot be completely and effectively decomposed and removed during the post-treatment and electrolysis of the residual oxidation solution. During the post-treatment and electrolysis process, a large amount of foam is generated due to the presence of emulsifiers, resulting in problems such as difficulty in normal operation and reduced electrolysis efficiency. Moreover, during long-term recycling, the foam will gradually accumulate and eventually make the cerium solution unusable.

[0011] Therefore, considering various factors, the synthesis process currently commonly used in industrial production is the "chromium method" route. However, in order to solve the problem of the chromium series oxidant process producing a large amount of chromium-containing wastewater, research on high-yield, green and environmentally friendly β-menadione synthesis technology has never stopped at home and abroad, but the results are not high. Summary of the Invention

[0012] In order to overcome the above-mentioned defects of the prior art, the present invention proposes a preparation method for the combined production of β-menadione and potassium permanganate, which is specifically achieved through the following technical solutions:

[0013] A preparation method for the combined production of β-menadione and potassium permanganate, characterized by comprising the following steps:

[0014] The potassium permanganate crystallization mother liquor obtained in the preparation process of potassium permanganate, acetic acid and 2-methylnaphthalene are reacted, and after the reaction, a first organic solvent is added for extraction, and an organic phase and an aqueous phase are obtained after the extraction, and the organic phase is washed with a saturated sodium bicarbonate solution. The aqueous phase obtained after the extraction and washing is evaporated to recover MnO2 as a raw material for producing potassium permanganate;

[0015] The organic phase is washed and then distilled to obtain a crude β-menadione product and recover acetic acid and 2-methylnaphthalene. A second organic solvent is added to the crude β-menadione product for crystallization to obtain a finished β-menadione product.

[0016] Furthermore, the method specifically includes the following steps:

[0017] A. Preparation of Potassium Permanganate

[0018] Under oxygen-containing conditions, a KOH solution is subjected to an oxidation reaction with a raw material containing MnO2. After the oxidation reaction is completed, potassium manganate is separated. The separated potassium manganate is washed with water, filtered, and the electrolyte is pretreated. The potassium manganate is then electrolyzed and crystallized after electrolysis to obtain potassium permanganate crystals and a potassium permanganate crystal mother liquor. The potassium permanganate crystals are centrifuged and dried to obtain a finished potassium permanganate product. The potassium permanganate crystal mother liquor is used to produce β-menadione, or is evaporated to recover KOH and MnO2 as raw materials for preparing potassium permanganate.

[0019] B. Preparation of β-menadione

[0020] The potassium permanganate crystallization mother liquor, acetic acid and 2-methylnaphthalene obtained in the potassium permanganate production process are reacted, and a first organic solvent is added after the reaction for extraction, and an organic phase and an aqueous phase are obtained after the extraction, and the organic phase is washed with a saturated sodium bicarbonate solution. The aqueous phase obtained after the extraction and washing is subjected to evaporation treatment to reclaim MnO2 as a raw material for producing potassium permanganate;

[0021] The organic phase is washed and then distilled to obtain a crude β-menadione product and recover acetic acid and 2-methylnaphthalene. A second organic solvent is added to the crude β-menadione product for crystallization to obtain a finished β-menadione product.

[0022] Furthermore, the molar ratio of 2-methylnaphthalene to potassium permanganate is 1:(0.5-2).

[0023] Furthermore, the mass ratio of 2-methylnaphthalene to acetic acid is 1:(15-25).

[0024] Furthermore, the first solvent is any one of chloroform, dichloromethane, and acetone.

[0025] Furthermore, the second solvent is any one of methanol, ethanol, and propanol.

[0026] Specifically, the mass ratio of the 2-methylnaphthalene to the first solvent is 1:(0.05-10).

[0027] Specifically, the crystallization temperature in the step of preparing potassium permanganate is 60-100°C.

[0028] Specifically, the crystallization temperature in the step of preparing β-menadione is 10-50°C.

[0029] Specifically, the temperature of the organic phase when washing with the saturated sodium bicarbonate solution is controlled at 10-50° C., and the mass ratio of the organic phase to the saturated sodium bicarbonate solution is 1:(0.25-4).

[0030] Compared with the prior art, the present invention has the following advantages:

[0031] 1. The present invention utilizes the crystallization mother liquor of potassium permanganate as an oxidant in the production process of β-menadione, thereby reducing the consumption of potassium permanganate products and lowering production costs;

[0032] 2. The present invention recycles MnO2 generated in the β-menadione reaction as part of the production raw materials into the potassium permanganate production process, thereby recycling and utilizing resources, reducing waste generated in the process, and protecting the environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0034] Figure 1 This is a schematic diagram of the process of Example 1 of the present invention. DETAILED DESCRIPTION

[0035] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0036] The present invention recycles potassium permanganate crystallization mother liquor as an oxidant for producing β-menadione, which can effectively reduce the consumption of potassium permanganate finished product and save costs. The reaction mechanism of potassium permanganate and β-menadione is as follows:

[0037]

[0038] The detailed steps are:

[0039] (1) Potassium permanganate is used as an oxidant to carry out the following reaction:

[0040] 2KMnO4+H2O→2KOH+2MnO2+3[O]

[0041] (2) Oxidation of 2-methylnaphthalene to β-menadione:

[0042]

[0043] Example 1

[0044] A. Preparation of Potassium Permanganate

[0045] Under oxygen or air conditions, a 20kg KOH solution is subjected to an oxidation reaction with a 30kg MnO2 raw material. After the oxidation reaction is completed, potassium manganate is leached with dilute KOH, and the separated potassium manganate is washed with water. After filtration, the electrolyte is pretreated to remove solid impurities and other metal ions therein, and then potassium permanganate is electrolyzed. After electrolysis, solid impurities are removed and crystallization is carried out at 60°C. After crystallization, potassium permanganate crystals and potassium permanganate crystal mother liquor are obtained. The potassium permanganate crystals are centrifuged and dried at 100°C to obtain potassium permanganate finished product with a yield of 90% and a purity of 99.0%. The potassium permanganate crystallization mother liquor contains about 20% potassium permanganate. 55% of the potassium permanganate crystallization mother liquor is taken out for the production of β-menadione. The potassium permanganate crystallization mother liquor pipeline must be insulated to reduce the occurrence of crystallization and prevent pipeline blockage. The remaining 45% of the potassium permanganate crystallization mother liquor is evaporated at a high temperature above 100°C, and KOH and MnO2 are recovered as raw materials for the preparation of potassium permanganate.

[0046] B. Preparation of β-menadione

[0047] 7.5kg 2-methylnaphthalene and 125kg acetic acid are heated with stirring to 70-100 ℃ in reactor, and the crystallization mother liquor containing potassium permanganate obtained in the potassium permanganate production process is slowly added to reactor, and continues to stir and constant temperature 3-6 hour.After reaction finishes, reaction mixture is quickly cooled to and is lower than 39 ℃, adds 15kg methylene dichloride and extracts, isolates organic phase, and with 30kg saturated NaHCO The aqueous solution is cleaned, and temperature is controlled at 35 ℃ during cleaning.Utilize distillation with the organic solvent in the organic phase extracted, acetic acid and unreacted 2-methylnaphthalene steam and reclaim, obtain the thick product of β-menadione, add methyl alcohol (second solvent) and carry out crystallization at 30 ℃ and obtain about 1kg β-menadione finished product.

[0048] The non-organic phase separated during the β-menadione production process contains MnO2 generated in the reaction and is recycled to the potassium permanganate production process. After mixing with the reflux crystallization mother liquor and evaporating, it is returned to the potassium permanganate oxidation reactor as part of the MnO2 raw material.

[0049] Example 2

[0050] A. Preparation of Potassium Permanganate

[0051] Under oxygen or air conditions, a 20kg KOH solution is subjected to an oxidation reaction with a 30kg MnO2 raw material. After the oxidation reaction is completed, potassium manganate is leached with dilute KOH, and the separated potassium manganate is washed with water. After filtration, the electrolyte is pretreated to remove solid impurities and other metal ions therein, and then potassium permanganate is electrolyzed. After electrolysis, solid impurities are removed and crystallization is carried out at 80°C to obtain potassium permanganate crystals and potassium permanganate crystal mother liquor. The potassium permanganate crystals are centrifuged and dried at 110°C to obtain potassium permanganate finished product with a yield of 87% and a purity of 99.5%. The potassium permanganate crystallization mother liquor contains about 20% potassium permanganate, and about 38.5% of the potassium permanganate crystallization mother liquor is taken out for the production of β-menadione. The potassium permanganate crystallization mother liquor pipeline must be insulated to reduce the occurrence of crystallization and prevent pipeline blockage. The remaining 61.5% of the potassium permanganate crystallization mother liquor is evaporated at a high temperature above 100°C, and KOH and MnO2 are recovered as raw materials for the preparation of potassium permanganate;

[0052] B. Preparation of β-menadione

[0053] 13kg 2-methylnaphthalene and 200kg acetic acid are heated with stirring to 70-100 ℃ in reactor, and the crystalline mother liquor that obtains containing potassium permanganate in the potassium permanganate production process slowly adds reactor, continues to stir and constant temperature 3-6 hour.After reaction finishes, reaction mixture is quickly cooled to and is lower than 39 ℃, adds 26kg methylene dichloride and extracts, isolates organic phase, and with 52kg saturated NaHCO The aqueous solution cleans, and temperature is controlled at 25 ℃ during cleaning.Utilize distillation that the organic solvent, acetic acid and unreacted 2-methylnaphthalene in the organic phase extracted are steamed and reclaimed, obtain the thick product of β-menadione, add methyl alcohol (second solvent) and carry out crystallization at 10 ℃ and obtain about 1kg β-menadione finished product.

[0054] The non-organic phase separated during the β-menadione production process contains MnO2 generated in the reaction, which is recycled into the potassium permanganate production process. After mixing with the refluxed crystallization mother liquor and evaporating, it is returned to the potassium permanganate oxidation reactor as part of the MnO2 raw material.

[0055] Example 3

[0056] A. Preparation of Potassium Permanganate

[0057] Under oxygen or air conditions, a 20kg KOH solution is subjected to an oxidation reaction with a 30kg MnO2 raw material. After the oxidation reaction is completed, the potassium manganate is leached with dilute KOH and washed with water to be separated. After filtration, the electrolyte is pretreated to remove solid impurities and other metal ions therein, and then the potassium permanganate is electrolyzed. After electrolysis, the solid impurities are removed and the product is crystallized at 95°C to obtain potassium permanganate crystals and potassium permanganate crystal mother liquor. The potassium permanganate crystals are centrifuged and dried at 120°C to obtain a finished potassium permanganate with a yield of 85% and a purity of 99.9%. The potassium permanganate crystallization mother liquor contains about 20% potassium permanganate, and about 82.5% of the potassium permanganate crystallization mother liquor is taken out for the production of β-menadione. The potassium permanganate crystallization mother liquor pipeline must be insulated to reduce the occurrence of crystallization and prevent pipeline blockage. The remaining 17.5% of the potassium permanganate crystallization mother liquor is evaporated at a high temperature above 100°C, and KOH and MnO2 are recovered as raw materials for the preparation of potassium permanganate;

[0058] B. Preparation of β-menadione

[0059] 7.5 kg of 2-methylnaphthalene and 185 kg of acetic acid are stirred and heated to 70-100°C in a reactor. The potassium permanganate crystallization mother liquor obtained during the potassium permanganate production process is then slowly added to the reactor. Stirring is continued and the temperature is maintained for 3-6 hours. After the reaction is completed, the reaction mixture is rapidly cooled to below 39°C and extracted with 75 kg of dichloromethane. The organic phase is separated and washed with 150 kg of saturated aqueous NaHCO₃ at 50°C. The organic solvent, acetic acid, and unreacted 2-methylnaphthalene in the extracted organic phase are removed and recovered by distillation to obtain a crude β-menadione product. Methanol (a second solvent) is then added and crystallized at 50°C to yield approximately 1 kg of finished β-menadione.

[0060] The non-organic phase separated during the β-menadione production process contains MnO2 generated in the reaction, which is recycled into the potassium permanganate production process. After mixing with the refluxed crystallization mother liquor and evaporating, it is returned to the potassium permanganate oxidation reactor as part of the MnO2 raw material.

[0061] The present invention provides a method for the combined production of β-menadione and potassium permanganate. For every kilogram of β-menadione produced, a minimum of 0.673 kilograms of MnO₂ is generated. This technical solution allows for the effective recovery of this portion of the reaction product, significantly reducing waste output during the combined production process. Furthermore, a minimum of 1.22 kilograms of finished KMnO₄ is eliminated from β-menadione production, saving costs.

[0062] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for the combined production of β-menadione and potassium permanganate, characterized in that: The following steps are involved: The potassium permanganate crystal mother liquor obtained in the potassium permanganate production process, acetic acid and 2-methylnaphthalene are reacted, and extraction and washing are performed after the reaction. The aqueous phase obtained after the extraction and washing is subjected to evaporation treatment to recover MnO2 as a raw material for producing potassium permanganate; The organic phase is distilled to obtain a crude β-menadione product and acetic acid and 2-methylnaphthalene are recovered, and an organic solvent is added to the crude β-menadione product for crystallization to obtain a β-menadione finished product; The preparation method for the combined production of β-menadione and potassium permanganate specifically comprises the following steps: A. Preparation of Potassium Permanganate Under oxygen-containing conditions, a KOH solution and a raw material containing MnO2 undergo an oxidation reaction. After the oxidation reaction is completed, potassium manganate is separated. The separated potassium manganate is washed with water, filtered, and the electrolyte is pretreated. The potassium manganate is then electrolyzed and crystallized. After the electrolysis, potassium permanganate crystals and a potassium permanganate crystal mother liquor are obtained. The potassium permanganate crystals are centrifuged and dried to obtain a potassium permanganate product. The potassium permanganate crystal mother liquor is used to produce β-menadione, or is evaporated to recover KOH and MnO2 as raw materials for preparing potassium permanganate. B. Preparation of β-menadione The potassium permanganate crystal mother liquor obtained in the process of preparing potassium permanganate, acetic acid and 2-methylnaphthalene are reacted, and after the reaction, a first organic solvent is added for extraction, and an organic phase and an aqueous phase are obtained after the extraction, and the organic phase is washed with a saturated sodium bicarbonate solution. The aqueous phase obtained after the extraction and washing is evaporated to recover MnO2 and KOH as raw materials for producing potassium permanganate; The organic phase is washed and then distilled to obtain a crude β-menadione product and to recover acetic acid and 2-methylnaphthalene. A second organic solvent is added to the crude β-menadione product for crystallization to obtain a β-menadione finished product.

2. The method for the combined production of β-menadione and potassium permanganate according to claim 1, characterized in that: The molar ratio of 2-methylnaphthalene to potassium permanganate is 1:(0.5-2).

3. The method for co-producing β-menadione and potassium permanganate according to claim 1, characterized in that: The mass ratio of 2-methylnaphthalene to acetic acid is 1:(15-25).

4. The method for co-producing β-menadione and potassium permanganate according to claim 1, characterized in that: The first organic solvent is any one of chloroform, dichloromethane and acetone.

5. The method for the combined production of β-menadione and potassium permanganate according to claim 1, characterized in that: The second organic solvent is any one of methanol, ethanol and propanol.

6. The method for the combined production of β-menadione and potassium permanganate according to claim 1, characterized in that: The mass ratio of the 2-methylnaphthalene to the first organic solvent is 1:(0.05-10).

7. The method for the combined production of β-menadione and potassium permanganate according to claim 1, characterized in that: The crystallization temperature in the step of preparing potassium permanganate is 60-100°C.

8. The method for the combined production of β-menadione and potassium permanganate according to claim 1, characterized in that: The crystallization temperature in the step of preparing β-menadione is 10-50°C.

9. The method for the combined production of β-menadione and potassium permanganate according to claim 1, characterized in that: The temperature of the organic phase when being washed with a saturated sodium bicarbonate solution is controlled at 10-50° C., and the mass ratio of the organic phase to the saturated sodium bicarbonate solution is 1:(0.25-4).

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