阅读说明：本技术 一种提高磷酸酯抗燃油耐水解性的净化方法 (Purification method for improving hydrolysis resistance of phosphate fire-resistant oil ) 是由 王德波 李世良 姚彬 于 2021-09-02 设计创作，主要内容包括：本发明公开了一种提高磷酸酯抗燃油耐水解性的净化方法,属于抗燃油技术领域,包括以下步骤：向洗涤釜内加入磷酸酯粗品和溶剂,将磷酸酯粗品和溶剂搅拌溶解后加入1%～5%碱水进行碱洗,升温充分搅拌后,通过离心泵将物料打入分层罐中静止,经重力沉降分离,将沉淀后的物料放入洗涤釜中；重复进行第二次碱洗；将沉淀后放入洗涤釜的物料内加入去离子水进行第三次洗涤,然后进行分层沉淀；将完成洗涤后的沉淀物料送入刮膜蒸发器中,蒸出溶剂、水及挥发物；最后将磷酸酯物料降温并取样分析。本发明操作简单便捷,磷酸酯粗品经有机溶剂溶解,通过1%～5%碱水和去离子水多次净化处理后,制得的磷酸酯物料的的水解安定性HS≤0.05,实现了提高磷酸酯抗燃油耐水解性的目的。(The invention discloses a purification method for improving hydrolysis resistance of phosphate fire-resistant oil, belonging to the technical field of fire-resistant oil, comprising the following steps: adding a phosphate ester crude product and a solvent into a washing kettle, stirring and dissolving the phosphate ester crude product and the solvent, adding 1-5% alkaline water for alkali washing, heating and fully stirring, pumping the material into a layering tank through a centrifugal pump for standing, performing gravity settling separation, and putting the precipitated material into the washing kettle; repeatedly carrying out second alkali washing; putting the precipitate into the material in a washing kettle, adding deionized water for washing for the third time, and then carrying out layered precipitation; feeding the washed precipitate material into a wiped film evaporator, and evaporating the solvent, water and volatile matters; and finally, cooling the phosphate material, sampling and analyzing. The method is simple and convenient to operate, the phosphate crude product is dissolved by the organic solvent, and after the phosphate crude product is purified for many times by 1-5% alkaline water and deionized water, the hydrolysis stability HS of the prepared phosphate material is less than or equal to 0.05, so that the aim of improving the hydrolysis resistance of the phosphate fire-resistant oil is fulfilled.)

1. A purification method for improving hydrolysis resistance of phosphate ester fire-resistant oil is characterized by comprising the following steps: the method comprises the following steps:

step one, adding a crude phosphate into a washing kettle;

adding a solvent into the washing kettle, wherein the mass of the solvent is 50-70% of that of the crude phosphate ester product;

step three, stirring and dissolving the crude phosphate ester and a solvent, and then adding 1-5% alkaline water for alkaline washing, wherein the mass of the 1-5% alkaline water is 60-90% of that of the crude phosphate ester;

step four, heating to 40-65 ℃, stirring fully, pumping the materials into a layering tank through a centrifugal pump for standing, performing gravity settling separation, draining a water layer, and putting the precipitated materials into a washing kettle;

step five, repeating the step three and the step four to carry out secondary alkali washing;

sixthly, putting the precipitate obtained in the fifth step into a material of a washing kettle, adding deionized water into the material to carry out third washing, wherein the mass of the deionized water is 60-90% of that of the crude phosphate product, and then repeating the fourth step to carry out layered precipitation;

step seven, feeding the washed precipitate material into a wiped film evaporator, and evaporating the solvent, water and volatile matters to obtain a purified phosphate ester material;

the hydrolytic stability HS of the phosphate material is less than or equal to 0.05;

the phosphate ester is triaryl phosphate ester.

2. The purification method for improving the hydrolysis resistance of phosphate ester fire-resistant oil as claimed in claim 1, wherein: and (4) cooling the phosphate ester material purified in the step seven to 80 ℃, and sampling and analyzing.

3. The purification method for improving the hydrolysis resistance of phosphate ester fire-resistant oil as claimed in claim 1, wherein: in the second step, the solvent is one or two of toluene, xylene, cyclohexane, methylcyclohexane, petroleum ether at 30-60 ℃, petroleum ether at 60-90 ℃, petroleum ether at 90-120 ℃, octanol, decanol and solvent oil.

Technical Field

The invention belongs to the technical field of fire-resistant oil, and particularly relates to a purification method for improving hydrolysis resistance of phosphate fire-resistant oil.

Background

The fire-resistant oil is classified into phosphate ester, silicate ester, petroleum-based oil, water-glycol emulsion, synthetic hydrocarbon, and the like. Among them, phosphate esters widely used in turbine electrohydraulic control systems are the most commonly used, and phosphate esters are classified into 3 types of aryl phosphate esters, alkyl phosphate esters and aryl-alkyl phosphate esters according to the structure. The aryl phosphate has better hydrolytic resistance, thermal oxidation stability and flame resistance, is mainly used as flame-resistant turbine oil in power systems and in the metallurgical industry except the fields of aviation, aerospace and the like, has higher viscosity, flash point, spontaneous combustion point and thermal decomposition temperature, and can meet the requirements of a regulating system of a large-capacity turbine set on a medium. The flame-retardant heat-insulating material does not burn at a high temperature, does not spread flame even if burning occurs under conditions of high temperature and burning, and automatically extinguishes the flame after a heat source is cut off, so that burning is stopped. In a power plant, if mineral turbine oil is used, once leakage occurs and high temperature is encountered, the possibility of fire is very high, and fire is caused. And the phosphate fire-resistant oil is used as a working medium of the regulating system, so that fire caused by oil leakage can be greatly reduced.

Compared with mineral turbine oil, the phosphate fire-resistant oil has excellent fire resistance (the spontaneous combustion point is more than 530 ℃), and compared with other synthetic hydraulic fluids, the phosphate fire-resistant oil has good stability and abrasion resistance. Most of adjusting systems of the steam turbines of the power plants are close to a superheated steam pipeline (the temperature of the superheated steam is over 540 ℃), the oil pressure of the adjusting systems reaches over 14 MPa, mineral oil (the spontaneous combustion point is only about 300 ℃) is used as a hydraulic adjusting working medium, and once leakage occurs, the danger of fire is very high. According to the statistics of the German insurance company, 94% of station fires occur in the oil system of the steam turbine, of which about 49% occur in the hydraulic system and 43% occur in the lubricating system. Therefore, phosphate fire-resistant oil is widely adopted as a hydraulic working medium in the regulating system of the steam turbines in various countries in the world at present in order to improve the fire-proof capability of the power plant and reduce the fire-fighting cost.

The phosphate fire-resistant oil has stronger polarity and is easy to absorb moisture in the air. Under appropriate conditions, such as severe stirring and the presence of acidic substances, hydrolysis can occur under the action of moisture, acidic phosphodiester, acidic phosphomonoester, phenolic substances and the like can be generated to different degrees, the acidic substances generated by hydrolysis have catalytic action on further hydrolysis of oil, and phosphoric acid and phenolic substances are generated after complete hydrolysis, so that corrosion is caused to a system, and the service life of the fire-resistant oil is influenced.

In the prior art, the improvement of the hydrolytic stability of oil is mainly realized by controlling the purity of synthetic raw materials, and natural raw materials such as phosphate synthesized by alkylphenol extracted from coal tar have better hydrolytic stability; it has also been reported that the hydrolysis of oil is blocked by the addition of hydrolysis-resistant additives such as piperazine-like compounds; in addition, the water content in the oil can be strictly controlled to achieve the aim of avoiding the hydrolysis of the oil. However, the above method has problems of high cost, complex process or poor effect.

Disclosure of Invention

The invention aims to provide a purification method which reduces the cost, simplifies the operation and improves the hydrolysis resistance of phosphate ester fire-resistant oil.

In order to achieve the purpose, the invention adopts the technical scheme that: a purification method for improving hydrolysis resistance of phosphate ester fire-resistant oil comprises the following steps:

step one, adding a crude phosphate into a washing kettle;

adding a solvent into the washing kettle, wherein the mass of the solvent is 50-70% of that of the crude phosphate ester product;

step three, stirring and dissolving the crude phosphate ester and a solvent, and then adding 1-5% alkaline water for alkaline washing, wherein the mass of the 1-5% alkaline water is 60-90% of that of the crude phosphate ester;

step four, heating to 40-65 ℃, stirring fully, pumping the materials into a layering tank through a centrifugal pump for standing, performing gravity settling separation, draining a water layer, and putting the precipitated materials into a washing kettle;

step five, repeating the step three and the step four to carry out secondary alkali washing;

sixthly, putting the precipitate obtained in the fifth step into a material of a washing kettle, adding deionized water into the material to carry out third washing, wherein the mass of the deionized water is 60-90% of that of the crude phosphate product, and then repeating the fourth step to carry out layered precipitation;

step seven, feeding the washed precipitate material into a wiped film evaporator, and evaporating the solvent, water and volatile matters to obtain a purified phosphate ester material;

and step eight, cooling the phosphate material to 80 ℃, and sampling and analyzing.

In step one, the phosphate ester is a triaryl phosphate ester.

In the second step, the solvent is one or two of toluene, xylene, cyclohexane, methylcyclohexane, petroleum ether at 30-60 ℃, petroleum ether at 60-90 ℃, petroleum ether at 90-120 ℃, octanol, decanol and solvent oil.

The hydrolytic stability HS of the phosphate material is less than or equal to 0.05.

Due to the adoption of the technical scheme, the operation is simple and convenient, after the crude triaryl phosphate is fully dissolved and dispersed by the organic solvent, phenolic substances are removed through 1-5% alkaline water in a gradient manner, and the deionized water is used for removing cations for multiple purification treatments, so that the hydrolysis stability HS of the prepared triaryl phosphate material is less than or equal to 0.05 and is far lower than the qualified standard that the hydrolysis stability HS is less than or equal to 0.5 specified in the standard DL/T571-2014 of the people's republic of China, and the purpose of improving the hydrolysis resistance of the phosphate fire-resistant oil is realized.

Detailed Description

The invention is further described with reference to the following examples:

phosphate ester fire-resistant oil is a synthetic hydraulic oil, some characteristics of which are quite different from those of mineral oil, and phosphate ester is a fire-resistant hydraulic oil which is more commonly used. Commonly used are tertiary phosphates of the general formula (RO)₃And P ═ O, wherein three R groups in the general formula are all aromatic groups, is triaryl phosphate, and the phosphate referred to herein is triaryl phosphate.

Example 1:

a purification method for improving hydrolysis resistance of phosphate ester fire-resistant oil comprises the following steps:

step one, adding 3kg of crude phosphate into a washing kettle;

step two, adding 2kg of solvent into the washing kettle, wherein the solvent is toluene and cyclohexane, and the weight ratio of toluene: cyclohexane =1: 1;

step three, stirring and dissolving the crude phosphate and a solvent, and adding 2kg of 3% alkaline water for alkaline washing;

step four, heating to 50-55 ℃, stirring fully, pumping the materials into a layering tank through a centrifugal pump for standing, performing gravity settling separation, draining a water layer, and putting the precipitated materials into a washing kettle;

step five, repeating the step three and the step four to carry out secondary alkali washing;

step six, putting the precipitate obtained in the step five into the material in a washing kettle, adding 2kg of deionized water into the material to carry out third washing, and then repeating the step four to carry out layered precipitation;

step seven, feeding the washed precipitate material into a wiped film evaporator, and evaporating the solvent, water and volatile matters to obtain a purified phosphate ester material;

and step eight, cooling the phosphate material to 80 ℃, and sampling and analyzing.

Example 2:

a purification method for improving hydrolysis resistance of phosphate ester fire-resistant oil comprises the following steps:

step one, adding 3kg of crude phosphate into a washing kettle;

step two, adding 1.6kg of solvent into the washing kettle, wherein the solvent is petroleum ether at the temperature of 60-90 ℃;

step three, stirring and dissolving the crude phosphate and a solvent, and then adding 2kg of 2% alkaline water for alkaline washing;

step four, heating to 40-45 ℃, stirring fully, pumping the materials into a layering tank through a centrifugal pump for standing, performing gravity settling separation, draining a water layer, and putting the precipitated materials into a washing kettle;

step five, repeating the step three and the step four to carry out secondary alkali washing;

step six, putting the precipitate obtained in the step five into the material in a washing kettle, adding 2kg of deionized water into the material to carry out third washing, and then repeating the step four to carry out layered precipitation;

step seven, feeding the washed precipitate material into a wiped film evaporator, and evaporating the solvent, water and volatile matters to obtain a purified phosphate ester material;

and step eight, cooling the phosphate material to 80 ℃, and sampling and analyzing.

Example 3:

a purification method for improving hydrolysis resistance of phosphate ester fire-resistant oil comprises the following steps:

step one, adding 3kg of crude phosphate into a washing kettle;

step two, adding 2.1kg of solvent into the washing kettle, wherein the solvent is dimethylbenzene;

step three, stirring and dissolving the crude phosphate and the solvent, and then adding 1.8kg of 4% alkaline water for alkaline washing;

step four, heating to 60-65 ℃, stirring fully, pumping the materials into a layering tank through a centrifugal pump for standing, performing gravity settling separation, draining a water layer, and putting the precipitated materials into a washing kettle;

step five, repeating the step three and the step four to carry out secondary alkali washing;

step six, putting the precipitate obtained in the step five into the material in a washing kettle, adding 1.8kg of deionized water into the material to carry out third washing, and then repeating the step four to carry out layered precipitation;

step seven, feeding the washed precipitate material into a wiped film evaporator, and evaporating the solvent, water and volatile matters to obtain a purified phosphate ester material;

and step eight, cooling the phosphate material to 80 ℃, and sampling and analyzing.

Example 4:

a purification method for improving hydrolysis resistance of phosphate ester fire-resistant oil comprises the following steps:

step one, adding 3kg of crude phosphate into a washing kettle;

step two, adding 1.9kg of solvent into the washing kettle, wherein the solvent is methylcyclohexane;

step three, stirring and dissolving the crude phosphate and the solvent, and then adding 2.1kg of 5% alkaline water for alkaline washing;

step four, heating to 50-55 ℃, stirring fully, pumping the materials into a layering tank through a centrifugal pump for standing, performing gravity settling separation, draining a water layer, and putting the precipitated materials into a washing kettle;

step five, repeating the step three and the step four to carry out secondary alkali washing;

step six, putting the precipitate obtained in the step five into the material in a washing kettle, adding 2.1kg of deionized water into the material to carry out third washing, and then repeating the step four to carry out layered precipitation;

step seven, feeding the washed precipitate material into a wiped film evaporator, and evaporating the solvent, water and volatile matters to obtain a purified phosphate ester material;

and step eight, cooling the phosphate material to 80 ℃, and sampling and analyzing.

The phosphate material samples of examples 1-4 were analyzed to obtain the following monitoring data for hydrolytic stability:

TABLE 1 hydrolysis stability monitoring data

The method is simple and convenient to operate, after the crude triaryl phosphate is fully dissolved and dispersed by the organic solvent, phenolic substances are removed through 1-5% alkaline water gradient, and the deionized water is used for removing cations for multiple purification treatments, so that the hydrolysis stability HS of the prepared triaryl phosphate is less than or equal to 0.05 and is far lower than the qualified standard that the hydrolysis stability HS is less than or equal to 0.5 specified in the standard DL/T571-2014 of the power industry of the people's republic of China, and the purpose of improving the hydrolysis resistance of phosphate fire-resistant oil is achieved.

The embodiments of the present invention have been described in detail, but the description is only for the preferred embodiments of the present invention and should not be construed as limiting the scope of the present invention. All equivalent changes and modifications made within the scope of the present invention should be covered by the present patent.