Preparation method of potassium iodate
A method combining hydrogen peroxide with hydroiodic acid and a potassium-containing alkaline compound addresses the inefficiencies of existing potassium iodate production, resulting in high-yield, environmentally friendly potassium iodate that meets pharmacopoeial standards.
Patent Information
- Application Number
- CN202411235254.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-04
- Publication Date
- 2024-12-10
AI Technical Summary
Existing methods for producing potassium iodate are costly, environmentally harmful, and do not meet the quality standards of the Chinese Pharmacopoeia, with issues such as toxic by-products, high energy consumption, and explosive raw materials.
A method involving the reaction of hydrogen peroxide with hydroiodic acid, catalyzed by concentrated acids, followed by addition of a potassium-containing alkaline compound, and subsequent refining steps to produce high-quality potassium iodate.
The method produces potassium iodate that is environmentally friendly, cost-effective, and meets the quality standards of the Chinese Pharmacopoeia with yields ranging from 85% to 90%.
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Abstract
Description
Technical Field
[0001] The invention belongs to the field of pharmaceutical chemistry, and in particular relates to a method for preparing potassium iodate. Background Art
[0002] Potassium iodate has attracted much attention due to its importance in preventing and treating endemic thyroid diseases, especially in the use of iodized salt and medicines. In addition, potassium iodate has also shown the potential to inhibit tumor growth in certain medical scenarios.
[0004] At present, the main methods for industrial production of potassium iodate include potassium chlorate oxidation, hydrogen peroxide oxidation, chlorine oxidation and electrolysis. Potassium chlorate oxidation produces highly toxic gas chlorine, and the raw material potassium chlorate itself is explosive, so this process route is not suitable for development; hydrogen peroxide oxidation requires the use of an electromagnetic reactor, which is relatively expensive; the raw material chlorine used in the chlorine oxidation method is also highly toxic; the electrolysis method consumes a lot of electricity and is also costly. Therefore, it is urgent to develop a new method for preparing potassium iodate, which is not only green and environmentally friendly, but also low in cost, high in yield, and the product quality must meet the standards of the Chinese Pharmacopoeia. Summary of the invention
[0005] In view of the shortcomings of the prior art, the present invention aims to provide a method for preparing potassium iodate. The preparation method provided by the present invention has the characteristics of low cost and high product yield, meets the requirements of green environmental protection, and is suitable for industrial production.
[0006] The purpose of the present invention is achieved through the following technical solutions: A method for preparing potassium iodate comprises the following steps: (1) mixing hydrogen peroxide and hydroiodic acid solution to react to obtain a first reactant; (2) under the action of a catalyst, mixing the first reactant and hydrogen peroxide to react to obtain a second reactant; (3) The second reactant is mixed with a potassium-containing alkaline compound to react. After the reaction is completed, the reactant is concentrated to dryness to obtain a crude potassium iodate product, which is then refined to obtain a fine potassium iodate product.
[0007] Preferably, in step (1), the molar ratio of hydroiodic acid in the hydroiodic acid solution to hydrogen peroxide in the hydrogen peroxide solution is 1.00:(0.50-1.00).
[0008] Preferably, in step (1), the concentration of hydrogen peroxide is 28.4%, and the concentration of hydroiodic acid solution is 56.6%.
[0009] Preferably, in step (1), the reaction temperature is -20 to 0°C, and the reaction time is 1 to 2 hours.
[0010] Preferably, in step (2), the catalyst is at least one of concentrated nitric acid, concentrated hydrochloric acid and concentrated sulfuric acid.
[0011] Preferably, in step (2), the mass ratio of the catalyst to the hydroiodic acid solution is 0.08:1.00.
[0012] Preferably, in step (2), the mass ratio of hydrogen peroxide to hydroiodic acid solution is (2.44-3.54):1.00.
[0013] Preferably, in step (2), the reaction temperature is 60-85° C., and the reaction time is 2-6 h.
[0014] Preferably, in step (3), the potassium-containing alkaline compound is at least one of potassium carbonate, potassium bicarbonate, potassium hydroxide and potassium acetate.
[0015] Preferably, the potassium-containing alkaline compound is first prepared into a solution and then mixed with the second reactant to react.
[0016] Preferably, in step (3), the amount of potassium-containing alkaline compound added is such that the pH of the system after the reaction is completed is 5.0-8.0.
[0017] Preferably, in step (3), the specific operation of refining includes: first, adding water to dissolve the crude product, and then performing a decolorization treatment; then, cooling the filtrate obtained after the decolorization treatment, and filtering it with a filter membrane; finally, concentrating the filtrate again to remove most of the solvent, and then cooling it to promote crystal precipitation, filtering, washing with water, and then drying.
[0018] Preferably, in the step of adding water to dissolve the crude product, the mass ratio of water to the crude product is 21.06:1.00.
[0019] Preferably, the decolorization treatment is achieved by adding activated carbon, the mass ratio of activated carbon to crude product is 0.19:1.00, and the temperature of the decolorization treatment is 60~100℃.
[0020] Preferably, the membrane filtration uses a membrane with a pore size of 0.45 μm.
[0021] Preferably, the filtrate is concentrated again to remove 95-98% of the solvent.
[0022] Preferably, cooling is cooling to 0-10°C.
[0023] Preferably, the water used for washing is 1-10°C water.
[0024] Compared with the prior art, the beneficial effects of the present invention include: The invention provides a method for preparing potassium iodate, which is not only green and environmentally friendly, but also low in cost and high in yield. The product quality meets the standards of the Chinese Pharmacopoeia and is suitable for industrial production. DETAILED DESCRIPTION
[0025] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.
[0026] The reagents used in the present invention can be purchased from the market or prepared by the method described in the present invention.
[0027] In the present invention, mmol means millimole, h means hour, g means gram, and eq. means equivalent.
[0028] Example 1 A preparation method of potassium iodate, the chemical reaction equation of the preparation method is as follows:
[0029] The specific steps are as follows: Add 20g (88.4928mmol, 1.00eq.) of hydroiodic acid solution to a 100mL three-necked flask, cool to -20°C, then drop 6.36g (53.0957mmol, 0.60eq.) of hydrogen peroxide, stir for 2h after dropping, add 1.53g (15.79597mmol, 0.18eq.) of concentrated nitric acid, heat to 85°C after addition, and drop 48.87g of hydrogen peroxide. After dropping, the reaction liquid becomes colorless, transparent and clear, stir for 6h, then cool to 30°C, drop potassium carbonate solution to adjust the pH of the system after the reaction to 8.0, and then concentrate Shrink to dryness to obtain 19.55g off-white crude potassium iodate, add 411.68g purified water to the crude potassium iodate, stir and dissolve completely at 30℃, add 3.79g activated carbon, heat to 100℃ and stir for 0.5h, then cool to 0℃ and keep warm and stir for 0.5h, filter through a filter membrane with a pore size of 0.45μm, and concentrate the filtrate under reduced pressure to remove 403.45g of water, then cool to 0℃ and keep warm for 2h, filter, rinse with purified water 3 times at 1℃, and finally vacuum dry at 70℃ for 3h to obtain 16.10g white powder, with a yield of 85% and a content of 100.0%. The remaining test items are as follows: 1. Clarity and solution color: clear and colorless; 2. Sulfate: not detected; 3. Iodide: 0.001%; 4. Loss on drying: 0.05%; 5. Heavy metals: not detected; 6. Arsenic salts: not detected. The product prepared in this example meets the requirements of the Chinese Pharmacopoeia.
[0030] Example 2 A preparation method of potassium iodate, the chemical reaction equation of the preparation method is as follows:
[0031] The specific steps are as follows: Add 20g (88.4928mmol, 1.00eq.) of hydroiodic acid solution to a 100mL three-necked flask, cool to 0°C, then drop 5.30g (44.2464mmol, 0.50eq.) of hydrogen peroxide, stir for 1h after dropping, add 1.53g (15.5094mmol, 0.18eq.) of concentrated hydrochloric acid, heat to 60°C after addition, and drop 70.80g of hydrogen peroxide. After dropping, the reaction liquid becomes colorless, transparent and clear, stir for 2h, and then cool to 30°C, drop potassium bicarbonate solution to adjust the pH of the system after the reaction to 5.0, and then concentrate to Dry to obtain 18.00g off-white crude potassium iodate, add 379.08g purified water to the crude potassium iodate, stir at 30℃ to dissolve completely, add 3.42g activated carbon, heat to 60℃ and stir for 0.5h, then cool to 10℃ and keep warm and stir for 0.5h, filter through a filter membrane with a pore size of 0.45μm, and concentrate the filtrate under reduced pressure to remove 360.13g of water, then cool to 10℃ and keep warm for 2h, filter, rinse with purified water 3 times at 10℃, and finally vacuum dry at 70℃ for 3h to obtain 17.04g white powder, with a yield of 90% and a content of 100.0%. The remaining test items are as follows: 1. Clarity and solution color: clear and colorless; 2. Sulfate: not detected; 3. Iodide: 0.0002%; 4. Loss on drying: 0.01%; 5. Heavy metals: not detected; 6. Arsenic salts: not detected. The product prepared in this example meets the requirements of the Chinese Pharmacopoeia.
[0032] Example 3 A preparation method of potassium iodate, the chemical reaction equation of the preparation method is as follows:
[0033] The specific steps are as follows: Add 20g (88.4928mmol, 1.00eq.) of hydroiodic acid solution to a 100mL three-necked flask, cool to -10°C, then drop 10.60g (88.4928mmol, 1.00eq.) of hydrogen peroxide, stir for 1.5h after the addition, add 1.53g (15.2878mmol, 0.18eq.) of concentrated sulfuric acid, heat to 72°C after the addition, and drop 60.00g of hydrogen peroxide. After the addition, the reaction liquid becomes colorless, transparent and clear, stir for 4h, and then cool to 30°C, drop potassium hydroxide solution to adjust the pH of the system after the reaction to 6.5. Then concentrated to dryness to obtain 19.20g off-white crude potassium iodate, 404.35g purified water was added to the crude potassium iodate, stirred at 30℃ to dissolve completely, 3.65g activated carbon was added, heated to 80℃ and stirred for 0.5h, then cooled to 5℃ and kept stirred for 0.5h, filtered through a filter membrane with a pore size of 0.45μm, the filtrate was concentrated under reduced pressure to remove 392.22g of water, then cooled to 5℃ and kept warm for 2h, filtered, rinsed with purified water 3 times at 5℃, and finally vacuum dried at 70℃ for 3h to obtain 16.67g white powder, with a yield of 88% and a content of 100.0%. The remaining test items are as follows: 1. Clarity and solution color: clear and colorless; 2. Sulfate: not detected; 3. Iodide: 0.001%; 4. Drying loss: 0.04%; 5. Heavy metals: not detected; 6. Arsenic salts: not detected. The product prepared in this example meets the requirements of the Chinese Pharmacopoeia.
[0034] Example 4 A preparation method of potassium iodate, the chemical reaction equation of the preparation method is as follows:
[0035] The specific steps are as follows: except for "adding potassium acetate solution to adjust the pH of the system after the reaction to 6.5", other operations are the same as those in Example 3.
[0036] Example 4 obtained 16.48 g of white powder, with a yield of 87% and a content of 100.0%. The remaining test items are as follows: 1. Clarity and solution color: clear and colorless; 2. Sulfate: not detected; 3. Iodide: 0.001%; 4. Loss on drying: 0.01%; 5. Heavy metals: not detected; 6. Arsenic salts: not detected. The product prepared in this example meets the requirements of the Chinese Pharmacopoeia.
[0037] Comparative Example 1 A preparation method of potassium iodate, the chemical reaction equation of the preparation method is as follows:
[0038] The specific steps are as follows: Add 20g (88.4928mmol, 1.00eq.) of hydroiodic acid solution to a 100mL three-necked flask, cool to 10°C, then drop 4.24g (35.3971mmol, 0.40eq.) of hydrogen peroxide, stir for 2h after the addition, add 1.53g (15.79597mmol, 0.18eq.) of concentrated nitric acid, heat to 85°C after the addition, drop 48.87g of hydrogen peroxide, stir for 6h after the addition, then cool to 30°C, drop potassium carbonate solution to adjust the pH of the system after the reaction to 8.0, and then concentrate to dryness to obtain 2 0.00g orange potassium iodate crude product, add 421.2g purified water to the potassium iodate crude product, stir at 30℃ to dissolve completely, add 3.80g activated carbon, heat to 100℃ and stir for 0.5h, then cool to 0℃ and keep stirring for 0.5h, filter through a filter membrane with a pore size of 0.45μm, and concentrate the filtrate under reduced pressure to remove 400.00g of water, then cool to 0℃ and keep warm for 2h, filter, rinse with purified water 3 times at 1℃, and finally vacuum dry at 70℃ for 3h to obtain 10.50g white powder, with a yield of 47.13% and a content of 85.0%. The product prepared in this comparative example does not meet the requirements of the Chinese Pharmacopoeia.
[0039] Comparative Example 2 A preparation method of potassium iodate, the chemical reaction equation of the preparation method is as follows:
[0040] The specific steps are as follows: Add 20g (88.4928mmol, 1.00eq.) of hydroiodic acid solution to a 100mL three-necked flask, cool to 0°C, then drop 5.30g (44.2464mmol, 0.50eq.) of hydrogen peroxide, stir for 1h after the addition, add 8.73g (88.4928mmol, 1.00eq.) of concentrated hydrochloric acid, heat to 100°C after the addition, drop 70.80g of hydrogen peroxide, stir for 2h after the addition, then cool to 30°C, drop potassium bicarbonate solution to adjust the pH of the system after the reaction to 8.0, and then concentrate to dryness to obtain 19 .00g gray potassium iodate crude product, add 400.14g purified water to the potassium iodate crude product, stir and dissolve completely at 30℃, add 3.61g activated carbon, heat to 60℃ and stir for 0.5h, then cool to 10℃ and keep warm and stir for 0.5h, filter through a filter membrane with a pore size of 0.45μm, and concentrate the filtrate under reduced pressure to remove 360.13g of water, then cool to 10℃ and keep warm for 2h, filter, rinse with purified water 3 times at 10℃, and finally vacuum dry at 70℃ for 3h to obtain 8.00g off-white powder, with a yield of 29.57% and a content of 70.0%. The product prepared in this comparative example does not meet the requirements of the Chinese Pharmacopoeia.
[0041] Comparative Example 3 A preparation method of potassium iodate, the chemical reaction equation of the preparation method is as follows:
[0042] The specific steps are as follows: Add 20g (88.4928mmol, 1.00eq.) of hydroiodic acid solution to a 100mL three-necked flask, cool to -10°C, then drop 10.60g (88.4928mmol, 1.00eq.) of hydrogen peroxide, stir for 1.5h after the addition, add 8.85g (88.4928mmol, 1.00eq.) of concentrated sulfuric acid, heat to 72°C after the addition, drop 60.00g of hydrogen peroxide, stir for 4h after the addition, then cool to 30°C, drop potassium hydroxide solution to adjust the pH of the system after the reaction to 6.5, and then concentrate to Dry to obtain 19.80g yellow potassium iodate crude product, add 416.99g purified water to the potassium iodate crude product, stir and dissolve completely at 30℃, add 3.76g activated carbon, heat to 80℃ and stir for 0.5h, then cool to 5℃ and keep warm and stir for 0.5h, filter through a filter membrane with a pore size of 0.45μm, concentrate the filtrate under reduced pressure to remove 350g of water, then cool to 5℃ and keep warm for 2h, filter, rinse with purified water 3 times at 5℃, and finally vacuum dry at 70℃ for 3h to obtain 7.00g white powder, with a yield of 17.74% and a content of 48%. The product prepared in this comparative example does not meet the requirements of the Chinese Pharmacopoeia.
[0043] Comparative Example 4 A preparation method of potassium iodate, the chemical reaction equation of the preparation method is as follows:
[0044] The specific steps are as follows: Add 20g (88.4928mmol, 1.00eq.) of hydroiodic acid solution to a 100mL three-necked flask, cool to -10°C, then drop 10.60g (88.4928mmol, 1.00eq.) of hydrogen peroxide, stir for 1.5h after the addition, add 8.85g (88.4928mmol, 1.00eq.) of concentrated sulfuric acid, heat to 72°C after the addition, drop 60.00g of hydrogen peroxide, stir for 4h after the addition, then cool to 30°C, drop potassium acetate solution to adjust the pH of the system after the reaction to 9.5, and then concentrate to dryness. 19.80g yellow potassium iodate crude product was obtained, 421.20g purified water was added to the potassium iodate crude product, and the solution was completely dissolved by stirring at 30°C, 3.80g activated carbon was added, and the mixture was heated to 80°C and stirred for 0.5h, then cooled to 5°C and stirred for 0.5h, filtered through a filter membrane with a pore size of 0.45μm, and the filtrate was concentrated under reduced pressure to remove 410.00g of water, then cooled to 5°C and kept warm for 2h, filtered, rinsed with purified water 3 times at 5°C, and finally vacuum dried at 70°C for 3h to obtain 9.00g of light yellow powder, with a yield of 28.51% and a content of 60%. The product prepared in this comparative example does not meet the requirements of the Chinese Pharmacopoeia.
[0045] The specific implementation of the present invention described above does not constitute a limitation on the protection scope of the present invention. Any other corresponding changes and modifications made based on the technical concept of the present invention should be included in the protection scope of the claims of the present invention.
Claims
1. A method for preparing potassium iodate, It is characterized in that The steps include: (1) mixing hydrogen peroxide and hydroiodic acid solution to react to obtain a first reactant; (2) mixing the first reactant and hydrogen peroxide to react under the action of a catalyst to obtain a second reactant; (3) The second reactant is mixed with a potassium-containing alkaline compound to react. After the reaction is completed, the reactant is concentrated to dryness to obtain a crude potassium iodate product, which is then refined to obtain a fine potassium iodate product.
2. The method for preparing potassium iodate according to claim 1, It is characterized in that The molar ratio of the hydroiodic acid in the hydroiodic acid solution and the hydrogen peroxide in the hydrogen peroxide in step (1) is 1.00:(0.50-1.00).
3. The method for preparing potassium iodate according to claim 1, It is characterized in that The reaction temperature in step (1) is -20 to 0°C, and the reaction time is 1 to 2 hours.
4. The method for preparing potassium iodate according to any one of claims 1 to 3, It is characterized in that The catalyst in step (2) is at least one of concentrated nitric acid, concentrated hydrochloric acid and concentrated sulfuric acid; The potassium-containing alkaline compound in step (3) is at least one of potassium carbonate, potassium bicarbonate, potassium hydroxide and potassium acetate.
5. The method for preparing potassium iodate according to claim 1, It is characterized in that The mass ratio of the catalyst to the hydroiodic acid solution in step (2) is 0.08:1.
00.
6. The method for preparing potassium iodate according to claim 5, It is characterized in that The mass ratio of the hydrogen peroxide solution in step (2) to the hydroiodic acid solution in step (1) is (2.44-3.54):1.
00.
7. The method for preparing potassium iodate according to claim 1, It is characterized in that The reaction temperature in step (2) is 60-85° C., and the reaction time is 2-6 hours.
8. The method for preparing potassium iodate according to claim 1, It is characterized in that The potassium-containing alkaline compound is first prepared into a solution and then mixed with the second reactant to react.
9. The method for preparing potassium iodate according to claim 1, It is characterized in that The amount of potassium-containing alkaline compound added in step (3) is such that the pH of the system after the reaction is completed is 5.0-8.
0.
10. The method for preparing potassium iodate according to claim 1, It is characterized in that The specific operation of the purification in step (3) includes: first, adding water to dissolve the crude product, and then performing a decolorization treatment; then, cooling the filtrate obtained after the decolorization treatment, and filtering it through a filter membrane; finally, concentrating the filtrate again to remove most of the solvent, and then cooling it to promote crystal precipitation, which is then filtered, washed with water, and then dried.