阅读说明：本技术 一种酮连氮水合肼副产物异丙基肼的分离提纯方法 (Separation and purification method of ketazine hydrazine hydrate byproduct isopropyl hydrazine ) 是由 陈尚思 周明 柴进祥 舒帮会 罗浩 于 2019-09-19 设计创作，主要内容包括：本发明公开了一种酮连氮水合肼副产物异丙基肼的分离提纯方法,包括以下步骤：将酮连氮法水合肼生产过程中分离得到的副产物异丙基肼废液进行蒸馏,控制蒸馏釜温度为100～108℃、馏出温度为95～100℃,将低沸物馏出后塔釜得浓缩后的异丙基肼溶液；将蒸馏后所得的塔釜异丙基肼溶液静置分层,除去水相后将含有异丙基肼的油相进行萃取,然后将萃取液进行蒸馏,蒸馏出萃取剂后控制馏出温度为106～108℃,收集馏分即得异丙基肼。本发明将含有异丙基肼的酮连氮水合肼副产物异丙基肼废液经蒸馏、静置分层、萃取、蒸馏四个步骤进行分离提纯,将低价值的异丙基肼有机废液转为化高质量的医药原料和中间体,不仅解决了酮连氮水合肼生产中有机废液的处理问题。(The invention discloses a separation and purification method of a ketazine hydrazine hydrate byproduct isopropyl hydrazine, which comprises the following steps: distilling a byproduct isopropyl hydrazine waste liquid obtained by separation in a ketazine process hydrazine hydrate production process, controlling the temperature of a distillation kettle to be 100-108 ℃ and the distillation temperature to be 95-100 ℃, and distilling a low-boiling-point substance to obtain a concentrated isopropyl hydrazine solution in a tower kettle; and standing and layering the distilled isopropyl hydrazine solution in the tower bottom, extracting an oil phase containing isopropyl hydrazine after removing a water phase, distilling an extract liquor, controlling the distillation temperature to be 106-108 ℃ after distilling an extractant, and collecting fractions to obtain the isopropyl hydrazine. The method separates and purifies the isopropylhydrazine waste liquid which is the byproduct of the ketazine hydrazine hydrate and contains the isopropylhydrazine through four steps of distillation, standing for layering, extraction and distillation, converts the low-value isopropylhydrazine organic waste liquid into high-quality medical raw materials and intermediates, and solves the problem of treating the organic waste liquid in the production of the ketazine hydrazine hydrate.)

1. A separation and purification method of a ketazine hydrazine hydrate byproduct isopropyl hydrazine is characterized by comprising the following steps:

(1) distilling a byproduct isopropyl hydrazine waste liquid obtained by separation in a ketazine process hydrazine hydrate production process, controlling the temperature of a distillation kettle to be 100-108 ℃ and the distillation temperature to be 95-100 ℃, and distilling a low-boiling-point substance to obtain a concentrated isopropyl hydrazine solution in a tower kettle;

(2) and (2) standing and layering the isopropyl hydrazine solution obtained in the step (1) into a water phase and an oil phase, extracting the oil phase containing isopropyl hydrazine after removing the water phase, distilling the extract liquor, controlling the distillation temperature to be 106-108 ℃ after distilling out the extractant, and collecting fractions to obtain the isopropyl hydrazine.

2. The method for separating and purifying ketazine hydrazine hydrate by-product isopropyl hydrazine according to claim 1, wherein the method comprises the following steps: and (3) in the distillation process of the step (1), when the temperature of the distillation kettle is more than 108 ℃ or the distillation temperature is more than 100 ℃, ending the distillation.

3. The method for separating and purifying ketazine hydrazine hydrate by-product isopropyl hydrazine according to claim 1, wherein the method comprises the following steps: the mass percentage of the isopropyl hydrazine in the isopropyl hydrazine waste liquid is 9-15%.

4. The method for separating and purifying ketazine hydrazine hydrate by-product isopropyl hydrazine according to claim 3, wherein the method comprises the following steps: the isopropyl hydrazine waste liquid comprises 0-0.5% of acetone, 0-0.5% of ketazine, 85-90% of water and the balance of organic byproduct impurities.

5. The method for separating and purifying ketazine hydrazine hydrate by-product isopropyl hydrazine according to claim 1, wherein the method comprises the following steps: ether was selected as the extractant.

6. The method for separating and purifying ketazine hydrazine hydrate by-product isopropyl hydrazine according to claim 5, wherein the method comprises the following steps: the extraction is repeated extraction, raffinate and extract liquid are obtained after extraction, and when the content of the isopropyl hydrazine in the raffinate is lower than 2 percent, or the content of the isopropyl hydrazine in the extract liquid accounts for more than 95 percent of the total content of the isopropyl hydrazine, the extraction is finished.

7. The method for separating and purifying ketazine hydrazine hydrate by-product isopropyl hydrazine according to claim 6, wherein the method comprises the following steps: the mass ratio of the extractant to the isopropyl hydrazine to be extracted in the oil phase is 4-6: 1 in each extraction.

8. The method for separating and purifying ketazine hydrazine hydrate by-product isopropyl hydrazine according to claim 1, wherein the method comprises the following steps: the standing and layering time is 0.5-1 h.

Technical Field

The invention relates to a separation and purification method of a ketazine hydrazine hydrate byproduct, in particular to a separation and purification method of a ketazine hydrazine hydrate byproduct isopropyl hydrazine.

Background

Hydrazine hydrate, also known as: hydrazine hydrate of the formula N₂H₄·H₂O, which is a strong reducing agent, is an important chemical raw material and is also a raw material of medicines, pesticides, dyes, foaming agents, developers and antioxidants; the method is used for deoxidation of boiler water, preparation of high-purity metal, synthesis and reduction of organic compounds, separation of rare elements, and also used for manufacturing rocket fuels and explosives, and the application field of hydrazine hydrate is continuously widened in recent years along with the progress of technology and the development of society. The production method of hydrazine hydrate mainly includes Raschig method, urea method, ketazine method, hydrogen peroxide method and air oxidation method. The production method of hydrazine hydrate mentioned in this invention is ketazine method, which adopts the reaction of acetone, sodium hypochlorite and ammonia to produce intermediate-ketazine, and the hydrolysis of ketazine to produce hydrazine hydrate. The main chemical reaction equation is as follows:

2NaOH+Cl₂→NaCl+NaClO+H₂O

NH₃+NaClO→NH₂Cl+NaOH

2CH₃COCH₃+NH₃+NH₂Cl+NaOH→(CH₃)₂C＝N-N＝(CH₃)₂C+3H₂o + NaCl (Synthesis reaction)

(CH₃)₂C＝N-N＝C(CH₃)₂+3H₂O→N₂H₄·H₂O+2CH₃COCH₃(hydrolysis reaction)

During the hydrolysis reaction, the following side reactions may also occur to form impurities:

CH₃COCH₃+H→CH₃COHCH₃(isopropyl alcohol)

CH₃COHCH₃+N₂H₄·H₂O→(CH₃)₂CHNHNH₂(isopropyl hydrazine)

Because the acetone generated by the hydrolysis reaction is reduced to obtain isopropanol, the isopropanol and hydrazine hydrate generate isopropyl hydrazine, the substance cannot be hydrolyzed to generate hydrazine hydrate, the raw material is consumed, and the yield of the hydrazine hydrate is reduced; because the boiling points of the isopropyl hydrazine and the ketazine are close, the isopropyl hydrazine cannot be brought out along with the acetone or hydrazine hydrate in a hydrolysis system, but the content of the isopropyl hydrazine is gradually accumulated in the hydrolysis system, the concentration of the isopropyl hydrazine slowly rises, raw materials are consumed, an effective reaction space is occupied, the productivity is reduced, the steam consumption is increased, and the ketazine hydrolysis rate is reduced. In order to remove the isopropyl hydrazine accumulated in the hydrolysis system, the chinese patent publication No. CN105384655A discloses a method for removing impurities in a ketazine process hydrazine hydrate hydrolysis system, the specific treatment method is as follows: when the mass percentage content of the isopropyl hydrazine in a hydrazine hydrate hydrolysis system reaches 6-10 percent, feeding a ketazine solution containing impurity isopropyl hydrazine into a secondary pressurized hydrolysis tower, introducing nitrogen for protection, controlling the tower pressure to be 0.25-0.3 MPa, the tower top temperature to be 108-110 ℃ and the tower kettle temperature to be 115-117 ℃, hydrolyzing the ketazine to form hydrazine hydrate and acetone, distilling out light components of isopropyl hydrazine and acetone from the tower top, and taking hydrazine hydrate as a tower kettle material; sending the gas mixture of propylhydrazine and acetone separated from the tower top into a first-stage pressurizing separation tower for rectification, controlling the tower pressure to be 0.18-0.25 MPa, the tower top temperature to be 100-102 ℃, the tower bottom temperature to be 108-110 ℃, distilling out light components of acetone and water vapor from the tower top, and obtaining isopropylhydrazine waste liquid at the tower bottom; in the embodiment, the content of the components in the obtained isopropyl hydrazine waste liquid is detected through experiments, wherein the content of acetone is 0.21%, the content of isopropyl hydrazine is 10.50%, the content of ketazine is 0.25%, and the rest components are water and other organic byproducts.

Isopropylhydrazine (isopropylhydrazine) has a structural formula of (CH)₃)₂CHNHNH₂Dissolving colorless transparent liquid with boiling point of 106-108 ℃/750mmHg in organic solution such as ether, chloroform and the like,water-insoluble; isopropyl hydrazine can be used as a raw material of a high-efficiency pesticide Mile Er, and is a common antidepressant. The common preparation method of isopropyl hydrazine comprises the following steps: (1) reacting bromo-isopropyl propane with a large amount of excess hydrazine hydrate, continuously extracting with a large amount of diethyl ether, and separating to obtain isopropyl hydrazine; (2) reacting ethyl carbazate with acetone, and then carrying out hydrogenation and ester protecting group removal to obtain the product; (3) the synthesis method of isopropyl hydrazine proposed in patent CN 105017064A comprises the steps of firstly, generating hydrazine hydrochloride from hydrazine hydrate and hydrochloric acid, reacting hydrazine hydrochloride with isopropanol to generate isopropyl hydrazine hydrochloride, dissociating with excess hydrazine hydrate to obtain isopropyl hydrazine and hydrazine hydrochloride, separating to obtain isopropyl hydrazine, and returning the hydrazine hydrochloride to the previous step; the preparation method of the isopropyl hydrazine has the advantages of multiple steps, complicated operation process and high parameter requirement.

Disclosure of Invention

The invention aims to solve the technical problem of providing a separation and purification method of ketazine hydrazine hydrate byproduct isopropyl hydrazine, which separates and purifies the ketazine hydrazine hydrate byproduct organic waste liquid containing isopropyl hydrazine, and converts the low-value isopropyl hydrazine organic waste liquid into high-quality medical raw materials and intermediates.

The technical scheme adopted by the invention for solving the technical problems is as follows: a separation and purification method of a ketazine hydrazine hydrate byproduct isopropyl hydrazine comprises the following steps:

(1) distilling a byproduct isopropyl hydrazine waste liquid obtained by separation in a ketazine process hydrazine hydrate production process, controlling the temperature of a distillation kettle to be 100-108 ℃ and the distillation temperature to be 95-100 ℃, and distilling a low-boiling-point substance to obtain a concentrated isopropyl hydrazine solution in a tower kettle;

(2) and (2) standing and layering the isopropyl hydrazine solution obtained in the step (1) into a water phase and an oil phase, extracting the oil phase containing isopropyl hydrazine after removing the water phase, distilling the extract liquor, controlling the distillation temperature to be 106-108 ℃ after distilling out the extractant, and collecting fractions to obtain the isopropyl hydrazine.

The extraction agent is selected from extraction agents which have good organic matter solubility and boiling points lower than that of isopropyl hydrazine, distillation is carried out to evaporate the extraction agent for recycling when the extraction agent is recycled, then the distillation temperature is controlled to be 106-108 ℃, and the isopropyl hydrazine is obtained by collecting fractions, namely isopropyl hydrazine is separated and purified again while the extraction agent is recycled.

Further, in the distillation process of the step (1), when the temperature of the distillation kettle is more than 108 ℃ or the distillation temperature is more than 100 ℃, the distillation is finished. In the distillation process, acetone, ketazine, water and other low-boiling-point organic matters in the isopropyl hydrazine waste liquid are distilled out, then isopropyl hydrazine is concentrated, the concentration of the concentrated isopropyl hydrazine solution is 78-82%, when the temperature of a distillation kettle is higher than 108 ℃ or the distillation temperature is higher than 100 ℃, the low-boiling-point substances in the isopropyl hydrazine waste liquid are basically completely distilled out, then the isopropyl hydrazine waste liquid is subjected to standing and layering, water-soluble impurities in the concentrated isopropyl hydrazine solution are removed, isopropyl hydrazine mixed in a water phase is concentrated in an oil phase to the greatest extent, impurity components entering an extraction stage are reduced, and the yield of isopropyl hydrazine in a subsequent extraction stage is improved.

Further, the mass percentage of the isopropyl hydrazine in the isopropyl hydrazine waste liquid is 9-15%.

Further, the isopropyl hydrazine waste liquid comprises 0-0.5% of acetone, 0-0.5% of ketazine, 85-90% of water and the balance of organic byproduct impurities.

Furthermore, diethyl ether is selected as an extracting agent. The extraction agent is selected according to the standard of easy obtaining, economy and good organic matter solubility, and the ether adopted by the invention has the greatest advantage that the boiling point is as low as 34.6 ℃ because the distribution coefficient of the isopropyl hydrazine in the ether is high, the energy-saving effect is obvious in the subsequent extraction agent distillation and recovery process, and the extraction agent can be recycled after distillation and recovery.

Furthermore, the extraction is multiple times of extraction, raffinate and extract are obtained after extraction, and when the content of the isopropyl hydrazine in the raffinate is lower than 2 percent, or the content of the isopropyl hydrazine in the extract accounts for more than 95 percent of the total content of the isopropyl hydrazine, the extraction is finished.

Furthermore, the mass ratio of the extracting agent to the isopropyl hydrazine to be extracted in the oil phase is 4-6: 1 in each extraction.

Further, the standing and layering time is 0.5-1 h. Generally, standing for 0.5-1h, and the phase boundary with obvious phase boundary can be regarded as the end of layering.

The invention has the beneficial effects that: the method comprises the steps of distilling, standing, layering, extracting and distilling the isopropyl hydrazine waste liquid which is a byproduct of ketazine hydrazine hydrate and contains isopropyl hydrazine, separating and purifying the isopropyl hydrazine waste liquid, wherein the purity of the obtained isopropyl hydrazine reaches more than 95%, and the yield of the isopropyl hydrazine reaches more than 92%, and the low-value isopropyl hydrazine organic waste liquid is converted into high-quality medical raw materials and intermediates, so that the problem of treating the organic waste liquid in the production of the ketazine hydrazine hydrate is solved, the high-quality isopropyl hydrazine is obtained only through simple physical operation, and the economic benefit of the production process of the ketazine hydrazine hydrate is greatly improved.

Drawings

FIG. 1 is a block diagram of a process flow for an embodiment of the present invention.

Detailed Description

The invention is further illustrated with reference to the following figures and examples.

The percentages referred to in the present invention are all percentages by mass unless otherwise specified.