CN109626331B - Method for recovering and separating iodine from cefepime waste liquid - Google Patents
Method for recovering and separating iodine from cefepime waste liquid Download PDFInfo
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- CN109626331B CN109626331B CN201811395550.2A CN201811395550A CN109626331B CN 109626331 B CN109626331 B CN 109626331B CN 201811395550 A CN201811395550 A CN 201811395550A CN 109626331 B CN109626331 B CN 109626331B
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Abstract
The invention discloses a method for recovering and separating iodine from cefepime waste liquid, which comprises the steps of respectively carrying out alkalization hydrolysis and acidification hydrolysis on the cefepime waste liquid, separating the cefepime waste liquid from an organic phase, carrying out oxidation and extraction on a water phase, dissolving an iodine elementary substance in the organic phase, and carrying out reduced pressure distillation, cooling and desublimation to recover the iodine elementary substance. The method has the advantages of simple operation, high iodine recovery rate and good purity, and is suitable for large-scale production.
Description
Technical Field
The invention relates to a method for recovering and separating iodine from cefepime waste liquid.
Background
Cefepime, a new generation of cephalosporin drugs, is mainly used for urinary tract infection, skin infection, abdominal infection, gynecological infection, septicemia and the like caused by sensitive bacteria infection, cefepime as a fourth generation of cephalosporin has deeper development of antibacterial action, balanced antibacterial property and good antibacterial activity on negative bacilli compared with a third generation of cephalosporin, and the characteristics make the cefepime become a drug with antibacterial property which is more widely accepted in clinical medicine in the future.
At present, most of cephalosporin medicines in China do not recover iodine from waste liquid, iodine ions in the cefepime waste liquid are sourced from trimethylsilyl iodoalkane, excessive trimethylsilyl iodosilane is needed for producing a 3-position substituted intermediate of cefepime in industry to enable iodination reaction to be complete, and then the iodine ions in the compound and anions undergo ion exchange reaction, so that all iodine in trimethylsilyl iodoalkane used for reaction exists in the cephalosporin medicine waste liquid in the form of iodine ions, but hydroiodic acid generated by the reaction exists in the solution and is combined with the cephalosporin compounds to form hydroiodide, so that the iodine is difficult to recover. Since iodine is a precious metal, this phenomenon causes iodine waste, and thus iodine recovery is imminent. The method for recovering iodine from iodine-containing waste liquid is mainly characterized by adopting oxidation method, reduction method, ion exchange method, air blowing method, floatation method, active carbon adsorption method, extractive distillation method and liquid membrane method to recover the iodine in the iodine-containing waste liquid in the form of crude iodine.
Disclosure of Invention
The invention provides a method for recovering and separating iodine from cefepime waste liquid, which combines oxidation-extraction-distillation, so that the recovery rate of iodine ions in the waste liquid is high, the purity is good, the process route is simple, and the method is suitable for large-scale production and utilization.
A method for recovering and separating iodine from cefepime waste liquid is characterized by comprising the following steps: respectively carrying out alkalization hydrolysis and acidification hydrolysis on the cefepime waste liquid, separating the cefepime waste liquid from an organic phase, oxidizing and extracting a water phase, dissolving an iodine simple substance in the organic phase, and carrying out reduced pressure distillation, cooling and desublimation to recover the iodine simple substance, wherein the method comprises the following steps:
(1) introducing waste liquid generated in cefepime production into a stirring reaction kettle, adding alkali, stirring and extracting, separating out a mixed solvent layer of methanol and acetone and an alkali liquid layer, circularly adding the alkali liquid into the reaction kettle, heating for hydrolysis, standing for layering to remove organic substances insoluble in water, then adding acid for acidification, continuously heating, stirring and hydrolyzing, and separating out the generated organic substances.
(2) Introducing the water phase into an oxidation-extraction tower, firstly adding an oxidant to oxidize the water phase into an iodine simple substance, then adding an extracting agent to extract until the purple red of the water solution disappears, standing, layering and combining organic phases; introducing waste gas generated by oxidation reaction into a sodium hydroxide solution for recycling treatment;
(3) the organic phase is put into a distillation kettle, and 70 to 80 percent of extractant is removed by reduced pressure distillation, and the extractant can be recycled;
(4) slowly heating the distillation still under the vacuum closed condition to sublimate the iodine into iodine vapor, cooling the iodine, desublimating the iodine for crystallization, and recovering the iodine.
Further preferably, in the step (1), the alkali is 20-30% sodium hydroxide or potassium hydroxide solution, the pH value is adjusted to 12-13, the heating hydrolysis temperature is 90-120 ℃, the acidification pH value is 0.5-2, and the stirring reaction is carried out for 1-3 h.
In the further preferable step (2), the oxidizing agent is sodium nitrite, the volume mass ratio of the cefepime waste liquid to the oxidizing agent is 1L: 8.6-22.5 g, and the oxidation reaction time is 10-30 min; the extractant is dichloromethane or diethyl ether; injecting an extracting agent into the tower in a tower top spraying mode, wherein the dosage of the extracting agent is 1-2 times of that of the waste liquid each time; the concentration of the sodium hydroxide for treating the tail gas is 20-30%.
Further preferably, in the step (3), the reduced pressure distillation temperature is 12-18 ℃, and the pressure is controlled at 0.08-0.15 MPa.
Further preferably, in the step (4), the temperature is programmed to 30 ℃ under a vacuum condition, and the temperature is raised to 1 ℃ for 10-15 minutes.
Adding 20-30% of sodium hydroxide or potassium hydroxide solution into the cefepime waste liquid obtained in the step (1), separating methanol and acetone from the waste liquid by destroying drug components, heating and hydrolyzing the residual alkali liquid to separate the generated organic matters from the alkali liquid, then acidifying and heating to further separate the organic matters, and separating a water phase and an organic phase by standing and layering, wherein iodine generated in the reaction is enriched in the water phase in the form of iodine negative ions.
The iodine ions in the step (2) are oxidized into iodine simple substances, the oxidant is sodium nitrite, compared with the method for recovering iodine in the prior art, sodium nitrite does not have peroxidation, and other processes adopt oxidants such as hydrogen peroxide, sodium hypochlorite, potassium hypochlorite, vanadium pentoxide and the like, so that I is easy to react-Oxidation to IO3 -The recovery rate of iodine is reduced, so the dosage of oxidant is strictly controlled in the reaction, sodium nitrite has no peroxidation reaction, and the use is convenient. Because the iodine simple substance easily sublimes, in order to avoid the sublimation of iodine extravagant, combine oxidation process and extraction process in the technology, because the iodine simple substance slightly dissolves into water, the extractant is sprayed by oxidation extraction tower top and is got into, fully contacts with iodine and dissolves, has avoided the leading to the fact of loss, and the extractant has selected low, the good dichloromethane and the ether of solubility of boiling point moreover, and the vacuum distillation temperature is low, has avoided the sublimation of iodine, makes things convenient for the separation and the recovery of extractant simultaneously.
And (3) introducing the organic solvent dissolved with iodine into a reduced pressure distillation kettle to evaporate most of the extractant, raising the temperature in vacuum by adopting a program to control the temperature slowly, ensuring that the iodine simple substance is completely changed into iodine vapor, and then performing desublimation to ensure that the high-purity iodine simple substance is obtained. In the device process, the alkaline hydrolysis and the acidic hydrolysis share one reaction tank, and the distillation-sublimation-condensation treatment shares one reduced pressure distillation tank, so that the device is simple, and the cost is saved.
The invention has the following beneficial effects:
(1) the technical problem solved by the invention is that the iodine ions in the cefepime waste liquid are recovered, the iodine ions are separated from organic matters by combining alkalization hydrolysis and acidification hydrolysis, the iodine ions are enriched in a water phase, the separation and recovery of iodine simple substances are facilitated, and in the device process, alkaline hydrolysis and acidic hydrolysis share one reaction tank.
(2) The iodine is recovered through oxidation, extraction, distillation and desublimation, the obtained iodine simple substance has high yield and good purity, and the distillation, sublimation and condensation processes share one reduced pressure distillation kettle, so the device is simple and the cost is saved; the oxidation-extraction combination improves the extraction rate of iodine and has less entrained impurities.
(3) Sodium nitrite is used as the oxidant, the dosage of the oxidant is not strictly controlled, and I in the reaction is avoided-Generation of IO by peroxidation3 -The process method is simple to operate, high in iodine recovery rate and good in purity, and is suitable for large-scale production.
Detailed Description
Example 1
Adding 3L of cefepime waste liquid into a stirring reaction kettle, wherein the alkali liquid is 20% sodium hydroxide, adjusting the pH value to 12, separating out the alkali liquid, stirring, heating, hydrolyzing, heating the temperature to 90 ℃, separating out an organic phase, adding 36% hydrochloric acid, adjusting the pH value to 0.5, continuing to heat, hydrolyzing for 3 hours, recovering a water phase, cooling, introducing into an oxidation extraction tower, carrying out oxidation reaction on 25.8g of sodium nitrite for 10 minutes, spraying dichloromethane into the tower top, extracting until mauve color in the water phase disappears, allowing the organic phase to flow into a reduced pressure distillation kettle at the pressure of 0.15MPa and the temperature of 12 ℃, evaporating most of dichloromethane serving as an extractant, recycling, continuing to heat the residual components in a sealed manner to 30 ℃ under a vacuum condition, rising 1 ℃ every 10 minutes, sublimating iodine simple substances, cooling the distillation kettle, and sublimating the iodine to obtain a pure product, wherein the recovery rate is.
Example 2
Adding 4L of cefepime waste liquid into a stirring reaction kettle, wherein the alkali liquid is 20% potassium hydroxide, adjusting the pH value to 13, separating out the alkali liquid, stirring, heating, hydrolyzing, heating at 120 ℃, separating out an organic phase, adding 36% hydrochloric acid to adjust the pH value to 2, continuously heating, hydrolyzing for 3 hours, recovering a water phase, cooling, introducing into an oxidation extraction tower, performing oxidation reaction on 90g of sodium nitrite for 20 minutes, spraying diethyl ether at the top of the tower, extracting until the mauve color in the water phase disappears, flowing the organic phase into a reduced pressure distillation kettle, heating at 0.08MPa and 18 ℃, recovering most of the diethyl ether serving as an extractant, continuously heating the rest components to 30 ℃ in a sealed manner under a vacuum condition, increasing 1 ℃ every 15 minutes, sublimating an iodine simple substance, cooling the distillation kettle, condensing iodine to obtain a pure product, wherein the recovery rate is 98.7%, and the content of the.
Example 3
Adding 1L of cefepime waste liquid into a stirring reaction kettle, wherein the alkali liquid is 30% sodium hydroxide, adjusting the pH value to 13, separating out the alkali liquid, stirring, heating, hydrolyzing, heating at 120 ℃, separating out an organic phase, adding 36% hydrochloric acid, adjusting the pH value to 1.5, continuing to heat, hydrolyzing for 2h, recovering a water phase, cooling, introducing into an oxidation extraction tower, performing oxidation reaction on 20g of sodium nitrite for 30min, spraying dichloromethane into the tower top, extracting until mauve in the water phase disappears, allowing the organic phase to flow into a reduced pressure distillation kettle at a pressure of 0.1MPa and a temperature of 15 ℃, evaporating most of dichloromethane serving as an extractant, recycling, continuing to heat the rest components to 30 ℃ in a sealed manner under a vacuum condition, increasing 1 ℃ every 15 minutes, sublimating an iodine simple substance, cooling the distillation kettle, condensing iodine to obtain a pure product, wherein the recovery rate is 98.8%, and the.
Comparative example 1
Adding 2L of cefepime waste liquid into a stirring reaction kettle, adding 30% potassium hydroxide as alkali liquid, adjusting the pH value to 12, separating out the alkali liquid, stirring, heating, hydrolyzing, heating to 90 ℃, separating out an organic phase, adding 36% hydrochloric acid to adjust the pH value to 2, continuously heating, hydrolyzing for 3 hours, recovering a water phase, cooling, introducing into an oxidation extraction tower, carrying out oxidation reaction on 20g of 30% hydrogen peroxide for 10 minutes, spraying diethyl ether at the tower top, extracting until the mauve color in the water phase disappears, flowing the organic phase into a reduced pressure distillation kettle, carrying out sublimation at the pressure of 0.12MPa and the temperature of 14 ℃, evaporating most of the extractant diethyl ether, continuously heating the rest components to 30 ℃ in a sealed manner under vacuum condition, rising 1 ℃ of iodine elementary substance per 10 minutes for sublimation, cooling and cooling the distillation kettle, and sublimating the iodine to obtain a pure product, wherein the.
Comparative example 2
Adding 3L of cefepime waste liquid into a stirring reaction kettle, wherein the alkali liquid is 20% sodium hydroxide, adjusting the pH value to 13, separating out the alkali liquid, stirring, heating, hydrolyzing, heating at the temperature of 110 ℃, separating out an organic phase, adding 36% hydrochloric acid, adjusting the pH value to 4, continuously heating, hydrolyzing for 1h, recovering a water phase, cooling, introducing into an oxidation extraction tower, carrying out oxidation reaction on 30g of 10% sodium hypochlorite for 20min, spraying diethyl ether at the tower top, extracting until mauve color in the water phase disappears, flowing the organic phase into a reduced pressure distillation kettle, carrying out sublimation at the pressure of 0.09MPa and the temperature of 16 ℃, evaporating most of the extractant diethyl ether, continuously heating the rest components to 30 ℃ in a sealed manner under vacuum condition, sublimating 1 ℃ iodine simple substance every 15 minutes, cooling the distillation kettle, condensing iodine to obtain a pure product, and recovering the rate of 81.
Comparative example 3
Adding 1L of cefepime waste liquid into a stirring reaction kettle, wherein the alkali liquid is 30% sodium hydroxide, adjusting the pH to 13, separating out the alkali liquid, stirring, heating, hydrolyzing, heating at 120 ℃, separating out an organic phase, adding 36% hydrochloric acid, adjusting the pH to 1, continuously heating, hydrolyzing for 2h, recovering a water phase, cooling, introducing into an oxidation extraction tower, performing oxidation reaction on 20g of sodium nitrite for 10min, spraying dichloromethane into the tower top, extracting until the mauve color in the water phase disappears, flowing the organic phase into a reduced pressure distillation kettle, heating at 0.1MPa and 15 ℃, recovering most of dichloromethane serving as an extractant, evaporating, hermetically heating the rest components to 30 ℃ under a vacuum condition, rising 5 ℃ every 15 minutes, sublimating an iodine simple substance, cooling the distillation kettle, and sublimating iodine to obtain a pure product, wherein the recovery rate is 84.6%.
Comparative example 4
Adding 4L of cefepime waste liquid into a stirring reaction kettle, wherein the alkali liquid is 30% sodium hydroxide, adjusting the pH value to 13, separating out the alkali liquid, stirring, heating, hydrolyzing, heating at 120 ℃, separating out an organic phase, adding 36% hydrochloric acid, adjusting the pH value to 1.5, continuing to heat, hydrolyzing for 2h, recovering a water phase, cooling, introducing into an oxidation extraction tower, performing oxidation reaction on 80g of sodium nitrite for 30min, spraying dichloromethane into the tower top, extracting until mauve in the water phase disappears, allowing the organic phase to flow into a reduced pressure distillation kettle at a pressure of 0.3MPa and a temperature of 30 ℃, evaporating most of dichloromethane serving as an extractant, recycling, continuing to heat the rest components to 30 ℃ in a sealed manner under a vacuum condition, rising 3 ℃ every 15 minutes, sublimating an iodine simple substance, cooling the distillation kettle, condensing iodine to obtain a pure product, and recovering rate of 84..
Comparative example 5
Adding 5L of cefepime waste liquid into a stirring reaction kettle, wherein the alkali liquid is 30% sodium hydroxide, adjusting the pH to 8, separating out the alkali liquid, stirring, heating, hydrolyzing, heating at 120 ℃, separating out an organic phase, adding 36% hydrochloric acid, adjusting the pH to 1.5, continuing to heat, hydrolyzing for 2h, recovering a water phase, cooling, introducing into an oxidation extraction tower, performing oxidation reaction on 100g of sodium nitrite for 30min, spraying dichloromethane into the tower top, extracting until mauve in the water phase disappears, allowing the organic phase to flow into a reduced pressure distillation kettle at a pressure of 0.1MPa and a temperature of 15 ℃, evaporating most of dichloromethane serving as an extractant, recycling, continuing to heat the rest components to 30 ℃ in a sealed manner under a vacuum condition, rising 1 ℃ every 15 minutes, sublimating an iodine simple substance, cooling the distillation kettle, condensing iodine to obtain a pure product, and recovering rate of 81.3%.
Comparative example 6
Adding 3L of cefepime waste liquid into a stirring reaction kettle, wherein the alkali liquid is 20% potassium hydroxide, adjusting the pH to 14, separating out the alkali liquid, stirring, heating, hydrolyzing, heating at 120 ℃, separating out an organic phase, adding 36% hydrochloric acid, adjusting the pH to 2, continuously heating, hydrolyzing for 3 hours, recovering a water phase, cooling, introducing into an oxidation extraction tower, carrying out oxidation reaction on 67.5g of sodium nitrite for 20 minutes, spraying ether at the top of the tower, extracting until mauve color in the water phase disappears, allowing the organic phase to flow into a reduced pressure distillation kettle at a pressure of 0.08MPa and a temperature of 18 ℃, evaporating most of ether serving as an extractant, recycling, continuously heating the rest components to 30 ℃ in a sealed manner under a vacuum condition, increasing 1 ℃ every 15 minutes, sublimating an iodine simple substance, cooling the distillation kettle, condensing iodine to obtain a pure product, and recovering 84.5%.
Claims (6)
1. A method for recovering and separating iodine from cefepime waste liquid is characterized by comprising the following steps: respectively carrying out alkalization hydrolysis and acidification hydrolysis on the cefepime waste liquid, separating the cefepime waste liquid from an organic phase, oxidizing and extracting a water phase, dissolving an iodine elementary substance in the organic phase, and carrying out reduced pressure distillation, cooling and desublimation to recover the iodine elementary substance, wherein the method comprises the following steps:
(1) introducing waste liquid generated in cefepime production into a stirring reaction kettle, adding alkali, stirring and extracting, separating out a mixed solvent layer of methanol and acetone and an alkali liquid layer, circularly adding the alkali liquid into the reaction kettle, heating for hydrolysis, standing for layering to remove organic substances insoluble in water, then adding acid for acidification, continuously heating, stirring and hydrolyzing, and separating out the generated organic substances;
(2) introducing the water phase into an oxidation-extraction tower, firstly adding an oxidant to oxidize the water phase into an iodine simple substance, then adding an extracting agent to extract until the purple red of the water solution disappears, standing, layering and combining organic phases; introducing waste gas generated by oxidation reaction into a sodium hydroxide solution for recycling treatment;
(3) the organic phase is put into a distillation kettle, reduced pressure distillation is carried out to remove 70 to 80 percent of the extractant, and the extractant is recycled;
(4) slowly heating the distillation still under the vacuum closed condition to sublimate the iodine into iodine vapor, cooling the iodine, desublimating the iodine for crystallization, and recovering the iodine.
2. The method for recovering and separating iodine from cefepime waste liquid according to claim 1, wherein in the step (1), the alkali is 20% -30% sodium hydroxide or potassium hydroxide solution, the pH value is adjusted to 12-13, the heating hydrolysis temperature is 90-120 ℃, the acidification pH value is 0.5-2, and the stirring reaction is carried out for 1-3 h.
3. The method for recovering and separating iodine from cefepime waste liquid according to claim 1, wherein in the step (2), the oxidizing agent is sodium nitrite, the volume-to-mass ratio of the cefepime waste liquid to the oxidizing agent is 1L: 8.6-22.5 g, and the oxidation reaction time is 10-30 min; the extractant is dichloromethane or diethyl ether.
4. The method for recovering and separating iodine from cefepime waste liquid according to claim 1, wherein in the step (2), the extractant is injected into the tower in a tower top spraying manner, and the dosage of the extractant is 1-2 times of that of the waste liquid; the concentration of the sodium hydroxide for treating the tail gas is 20-30%.
5. The method for recovering and separating iodine from cefepime waste liquid according to claim 1, wherein in the step (3), the reduced pressure distillation temperature is 12-18 ℃, and the pressure is controlled to be 0.08-0.15 MPa.
6. The method for recovering and separating iodine from cefepime waste liquid according to claim 1, wherein in the step (4), the temperature is programmed to 30 ℃ in vacuum, and the temperature is raised to 1 ℃ in 10-15 minutes.
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| CN108862199A (en) * | 2018-06-28 | 2018-11-23 | 广东先导稀材股份有限公司 | The method of iodine is recycled in the waste liquid of trimethyl gallium containing iodine |
| CN112028020B (en) * | 2020-09-02 | 2021-06-22 | 山东博苑医药化学股份有限公司 | Process for recovering iodine from iodine bromide-containing medical organic waste liquid |
| CN112194204A (en) * | 2020-09-10 | 2021-01-08 | 昆明铂锐金属材料有限公司 | Preparation method of high-purity rhodium triiodide |
| CN114715848B (en) * | 2021-01-04 | 2023-09-12 | 中国科学院江西稀土研究院 | Method for recovering iodine from iodine-containing solution |
| CN117654423B (en) * | 2024-02-01 | 2024-04-26 | 中国科学院地球环境研究所 | System and method for extracting iodine in different occurrence forms in sediment |
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| CN106430105A (en) * | 2016-10-10 | 2017-02-22 | 云南民族大学 | Method for recycling iodine from acetic acid factory iodine-containing waste liquor |
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