Process for the preparation of diisooctyl phosphite intermediate and use of the intermediate in the preparation of P507

Abstract

The application belongs to the technical field of fine chemical product preparation, and particularly relates to a preparation method of diisooctyl phosphite intermediate and application of the intermediate in preparation of P507. The preparation method of the diisooctyl phosphite intermediate comprises the following steps: adding phosphorus trichloride into isooctanol by liquid dropping, controlling dropping speed, dropping pressure and reaction temperature, obtaining a diisooctyl phosphite mixture, removing impurities from the diisooctyl phosphite mixture by gas-phase ammonia neutralization or high-vacuum HCl removal, distilling chloroisoctane, collecting chloroisoctane byproduct, and finally obtaining diisooctyl phosphite. The preparation method of the diisooctyl phosphite intermediate is simple in operation, mild in condition, good in environmental protection, high in purity and yield of the prepared intermediate, and the application of the diisooctyl phosphite intermediate in preparation of P507 is high in purity of the prepared P507.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of fine chemical product preparation, and particularly relates to a preparation method of diisooctyl phosphite intermediate and application of the intermediate in preparation of P507. BACKGROUND

[0002] P507 (2-ethylhexyl phosphonic acid mono-2-ethylhexyl ester) has a structural formula of P507 is an important organic phosphorus extractant, and is widely used in separation and purification of rare earth metals, rare metals and transition metals. Due to its excellent extraction performance and selectivity, P507 has important industrial application value in the fields of hydrometallurgy, nuclear fuel reprocessing and wastewater treatment. In recent years, with the increasing strategic position of rare earth resources, the demand for P507 continues to grow, and the requirements for its purity and performance are also increasing. At present, there are mainly three methods to synthesize P507: one is to react 2-ethylhexyl phosphorodichloridate with 2-ethylhexanol to obtain the corresponding phosphonyl chloride, and then hydrolyze to obtain P507; the second is to react 2-ethylhexyl phosphonic acid with chloro-2-ethylhexane to obtain P507; the third is to hydrolyze O-O-di(2-ethylhexyl)-ethylhexyl phosphonate to remove one ester group to obtain P507. However, the above three methods are prone to generate monoester, diester, triester and other by-products in the reaction process, which affects the purity and performance of P507, and there are many by-products. In addition, some raw materials have high cost and complex preparation process, such as 2-ethylhexyl phosphorodichloridate and 2-ethylhexyl phosphonic acid. There are also problems of harsh reaction conditions and environmental protection, such as the need for neutralization or separation treatment of HCl or alcohol generated in the reaction, which produces a large amount of wastewater or waste liquid and increases the environmental protection cost.

[0003] Diisooctyl phosphite (structural formula ) as a key intermediate for synthesizing P507 or P204 organic phosphorus extractant, its traditional preparation process has significant technical bottlenecks. At present, the mainstream process uses phosphorus trichloride and isooctanol (2-ethylhexanol) to directly react to generate diisooctyl phosphite, but this process has problems such as poor reaction selectivity, many by-products, and low purity of target product.

[0004] In industrial production, some enterprises omit the distillation purification step to directly enter the subsequent reaction in order to simplify the process and save costs; or use 10% alkaline solution to wash the reaction mixture to remove residual HCl gas and neutralize to neutral. Although such operations can reduce costs in the short term, they will introduce water, which will cause multiple negative effects:

[0005] Water and isooctanol are partially miscible, and a small amount of water is entrained in the light components evaporated during the synthesis of diisooctyl phosphite, which enters the subsequent esterification reaction system;

[0006] Intermediates containing water are prone to hydrolysis during distillation and purification, which further reduces the purity of the product.

[0007] Excessive isooctyl alcohol forms a miscible system with water, producing high-COD NaCl wastewater, which increases the difficulty of environmental treatment.

[0008] The aforementioned problems severely restrict the efficiency and economy of large-scale production of diisooctyl phosphite, and there is an urgent need to develop new processes to improve reaction selectivity, reduce by-product formation, and avoid the introduction of the aqueous phase.

[0009] Therefore, diisooctyl phosphite is the first step in the synthesis of P507 as an organic extractant, and its quality determines the quality of subsequent diisooctyl phosphoate and P507 products. During the synthesis of diisooctyl phosphite, byproducts such as monoesters and trimers are formed. Furthermore, diisooctyl phosphite itself is structurally unstable and easily hydrolyzes to form monoesters under high temperature and acidic / alkaline conditions. These impurities cannot be separated in subsequent organic synthesis processes due to their high boiling points, resulting in high impurity content in the P507 product and a bimodal chromatographic appearance. Summary of the Invention

[0010] The technical problem to be solved by the present invention is to overcome the above-mentioned deficiencies of the prior art and provide a method for preparing diisooctyl phosphite intermediate, which is simple to operate, mild under mild conditions, and environmentally friendly. The prepared intermediate diisooctyl phosphite has high purity and high yield. The present invention also provides the application of diisooctyl phosphite intermediate in the preparation of P507, and the prepared P507 has high purity.

[0011] The preparation method of the diisooctyl phosphite intermediate of the present invention includes the following steps: adding phosphorus trichloride dropwise to isooctanol (…) The reaction was carried out in a controlled manner, with the dropping rate controlled at 1.0 mL / min to 1.5 mL / min, the dropping pressure controlled at -0.020 MPa to -0.030 MPa, the reaction temperature controlled at 20℃ to 25℃, and the reaction time controlled at 1 h to 1.5 h, to obtain a mixture of diisooctyl phosphite. The diisooctyl phosphite mixture was then subjected to gas-phase ammonia neutralization or high-vacuum deHCl removal to remove impurities, and its acidity was found to be below 3.33 mg NaOH / g. Chloroisooctane ( The distillation process yields chloroisooctane byproducts, which are collected and ultimately diisooctyl phosphite.

[0012] The specific steps of the gas-phase ammonia neutralization method are as follows: a mixture of ammonia and nitrogen is introduced into the diisooctyl phosphite mixture and stirred. The gas flow rate is controlled at 800~1000 mL / min until the acidity is below 3.33 mg NaOH / g. Then, the mixture is filtered until the filtrate is clear, yielding a deacidified mixture. The volume ratio of ammonia to nitrogen is 1:9~2:8.

[0013] The high vacuum de-HCl method has the following specific steps: the temperature of the diisooctyl phosphite mixture is kept at 55-65℃, the dropping speed is controlled at 3.0-4.5 mL / min by using a negative pressure system at a pressure of -0.090 to -0.095 MPa, and the mixture is dropped through a thorn-shaped fractionating column until the acidity is below 3.33 mg NaOH / g, to obtain the mixture after de-acidification.

[0014] The negative pressure system comprises a constant pressure funnel, a thorn-shaped fractionating column, a 2XZ-2 rotary vane vacuum pump, and a round-bottom flask, a silica gel hose, a Y-shaped pipe, a rubber plug, etc.

[0015] The distillation is carried out at a pressure of -0.095 MPa, the temperature is first raised at a speed of 2.0-3.0℃ / min to 110-120℃, then the temperature is continuously raised to 130-150℃ after the chloroiso-octane is discharged, and the distillation is ended when no chloroiso-octane is evaporated.

[0016] The reaction temperature of the diisooctyl phosphite mixture is controlled by an ice-water bath during the reaction, and the hydrogen chloride gas generated during the reaction is absorbed by a hydrogen chloride absorption device.

[0017] The application of the diisooctyl phosphite intermediate in the preparation of P507 comprises the following steps:

[0018] (1) Preparation of sodium iso-octyl alcohol: iso-octyl alcohol is heated to 60-70℃, sodium hydroxide is added and mixed, and then heated to 130-150℃, and kept for 2.5-3.5 h; after the heat preservation is completed, the heating jacket is removed, the mixed liquid is cooled to the alkali clumps, and the solid alkali is heated and dissolved and then transferred out; the liquid phase is transferred to a four-necked flask, the heating jacket is opened, the temperature is raised to 130-150℃ at a speed of 2.0-3.0℃ / min, and the liquid phase and gas phase temperatures are noted; after the distillation is completed, the content of iso-octyl alcohol is 20-25%;

[0019] (2) Condensation of diisooctyl iso-octyl phosphonate: the prepared diisooctyl phosphite intermediate is mixed with the sodium iso-octyl alcohol mixture prepared in step (1), heated to 140-150℃ for reaction, until no iso-octyl alcohol is evaporated, then chloroiso-octane collected in the preparation of diisooctyl phosphite intermediate is added, and reacted at 180-190℃ for 3-4 h; the temperature is first lowered to 80-90℃ and then raised for distillation until no gas phase is discharged, and then the temperature is lowered to room temperature, dissolved with water, and separated into phases to obtain the organic phase; the organic phase is refined at 230-240℃ to obtain diisooctyl iso-octyl phosphonate.

[0020] (3) Preparation of P507 sodium salt: the prepared diisooctyl isooctyl phosphonate is mixed with a sodium hydroxide solution, heated to 120-130°C and stirred, normal pressure distillation is performed for 1.5-2.5h, water is added and stirred at 500-1000r / min until completely dissolved, stirring is stopped, and the water is drained to obtain the P507 sodium salt;

[0021] (4) Preparation of P507: hydrochloric acid is added to the prepared P507 sodium salt to acidify the oil phase to a pH of 0.8-1.2, then the water is drained, water is added to the oil phase to wash until the pH of the oil phase is 4-5, and the obtained oil phase is post-treated to obtain P507.

[0022] The mass concentration of the sodium hydroxide solution in step (3) is 46%-48%; and the mass concentration of the hydrochloric acid in step (4) is 34%-36%.

[0023] The post-treatment step of step (4) is: the obtained oil phase is distilled at a gas phase temperature of 85-90°C under a vacuum of-0.090MPa to-0.095MPa until no gas phase is generated, then the temperature is continuously increased to 160-180°C, and the vacuum is-0.1MPa until the steam temperature of the distillation starts to drop, and the process is ended, and the temperature is lowered to room temperature.

[0024] Specifically, the preparation of P507 includes the following steps:

[0025] (1) Phosphorus trichloride is added dropwise to isooctanol under liquid submersion to react, the dropwise speed is controlled to be 1.0mL / min-1.5mL / min, the dropwise pressure is controlled to be-0.020MPa to-0.030MPa, the reaction temperature is controlled to be 20-25°C, the reaction time is 1-1.5h, a diisooctyl phosphite mixture is obtained, the diisooctyl phosphite mixture is treated by gas phase ammonia neutralization or high vacuum HCl removal to remove impurities, the acidity is detected to be 3.33mgNaOH / g or less, chloroisoctane is continuously distilled and collected to obtain chloroisoctane by-product, and finally diisooctyl phosphite is obtained.

[0026] (2) Preparation of sodium isooctylate: isooctanol is heated to 60-70°C and mixed with sodium hydroxide solid, then heated to 130-150°C, and kept for 2.5-3.5h, after the keeping, the heating jacket is removed, the mixed liquid is cooled to the alkali to be solidified, the solid alkali is heated and dissolved, and then transferred out; the liquid phase is transferred to a four-necked flask, the heating jacket is opened, and the temperature is increased to 130-150°C at a speed of 2.0-3.0°C / min, the liquid phase and gas phase temperatures are noted, and after the distillation is completed, the content of isooctanol is 20%-25%.

[0027] (3) Synthesis of diisooctyl phosphinic acid diisooctyl ester: the prepared diisooctyl phosphite intermediate is mixed with the sodium isooctyl alcohol mixture prepared in step (1), and the mixture is heated to 140-150 DEG C and reacted until no isooctyl alcohol is evaporated, then the chlorinated isooctane collected in the preparation of diisooctyl phosphite intermediate is added, and the mixture is reacted at 180-190 DEG C for 3-4 h, distilled at 80-90 DEG C until no gas phase is generated, cooled to room temperature, dissolved in water, and separated to obtain the organic phase, which is refined at 230-240 DEG C to obtain diisooctyl phosphinic acid diisooctyl ester;

[0028] (4) Preparation of P507 sodium salt: the prepared diisooctyl phosphinic acid diisooctyl ester is mixed with a sodium hydroxide solution, heated to 120-130 DEG C and stirred, and distilled at normal pressure for 1.5-2.5 h, then water is added and stirred at 500-1000 r / min until completely dissolved, the stirring is stopped, and the water is drained to obtain P507 sodium salt;

[0029] (5) The prepared P507 sodium salt is acidified by adding hydrochloric acid to make the pH of the oil phase 0.8-1.2, then the water is drained, water is added to the oil phase to wash until the pH of the oil phase is 4-5, and the obtained oil phase is treated to obtain P507.

[0030] In the preparation of diisooctyl phosphite, the PCl3 is added dropwise under liquid, the PCl3 is added through a constant pressure funnel extended dropwise conduit to the liquid surface of isooctyl alcohol, the dropwise speed is controlled, a micro negative pressure is maintained during the dropwise process, the negative pressure is increased after the dropwise process is completed, and most of the HCl gas is evaporated, the liquid dropwise addition ensures the effective use of PCl3, prevents the PCl3 from being sucked away after being added to the liquid surface due to the violent heat release of the reaction, and ensures the reaction contact area, so that the PCl3 is more effectively used.

[0031] The synthesis reaction formula of the diisooctyl phosphite of the application is:

[0032] .

[0033] The synthesis reaction formula of diisooctyl phosphinic acid diisooctyl ester is:

[0034] ,

[0035] .

[0036] The synthesis reaction formula of P507 is:

[0037] ,

[0038] .

[0039] The present application adopts gas phase ammonia neutralization method and high vacuum HCl removal method in the preparation of diisooctyl phosphite, the gas phase ammonia neutralization method neutralizes HCl gas in the diisooctyl phosphite and chloroisoalkane mixture by passing mixed gas of ammonia and nitrogen into the mixture, forms NH4Cl, and removes NH4Cl solid by filtration in the later stage, the high vacuum HCl removal method first heats the mixture to 60 DEG C under the condition of-0.095 MPa negative pressure, transfers the mixture to a negative pressure system (the system is composed of a 1000 mL constant pressure funnel, a 1.2 m thorn-shaped fractionating column and a 1000 mL round bottom flask, a 2XZ-2 rotary vane vacuum pump, silica gel hose and the like), controls the dropping speed of the material by the constant pressure funnel at 3.0 mL / min to 4.5 mL / min, drops into the round bottom flask through the thorn-shaped fractionating column, increases the surface area of the material by the thorn-shaped fractionating column so that HCl gas is more easily removed, and the thorn-shaped fractionating column is kept at 60 DEG C, without by-products and waste water.

[0040] Compared with the prior art, the present application has the beneficial effects that:

[0041] (1) The preparation of diisooctyl phosphite in the present application adopts gas phase ammonia neutralization method and high vacuum HCl removal method, no new impurities are formed in the organic synthesis reaction process, the yield of the obtained diisooctyl phosphite is equivalent to that of the traditional alkali neutralization method, but the content of the diisooctyl phosphite is higher than that obtained by the alkali neutralization method, and the content is as high as 96%.

[0042] (2) The preparation of diisooctyl phosphite in the present application adopts gas phase ammonia neutralization method and high vacuum HCl removal method, which greatly reduces the amount of waste water and the cost of waste water treatment, and the treatment cost of a large amount of high-salt, high-COD and high-phosphorus waste water is extremely high, which can only be treated by evaporation and concentration, and the treatment cost of each ton of waste water is about 200 yuan. Although the energy consumption of the gas phase ammonia neutralization method is increased, the cost of each ton of P507 product produced by the method is still reduced by 900 to 950 yuan. Although the high vacuum HCl removal method increases part of the power consumption, the cost of each ton of P507 product produced by the method is still reduced by about 1200 yuan. Therefore, compared with the traditional alkali neutralization method in the deacidification step, the cost of the present application is low.

[0043] (3) The P507 product prepared by the present application has high content and high yield, which reduces the cost of the whole process production, reduces the treatment of waste water and waste gas, and reduces the cost of environmental protection. BRIEF DESCRIPTION OF DRAWINGS

[0044] Figure 1 It is the nuclear magnetic resonance P spectrum of the diisooctyl phosphite intermediate prepared in Example 1.

[0045] Figure 2 It is the nuclear magnetic resonance P spectrum of the diisooctyl phosphite standard sample.

[0046] Figure 3 NMR H spectrum of the diisooctyl phosphite intermediate prepared in Example 1.

[0047] Figure 4 Internal standard curve of the diisooctyl phosphite intermediate prepared in Example 1 when subjected to gas phase detection.

[0048] Figure 5 NMR P spectrum of the diisooctyl phosphite intermediate prepared in Example 3.

[0049] Figure 6 NMR P spectrum of the diisooctyl phosphite intermediate prepared in Comparative Example 1. DETAILED DESCRIPTION

[0050] The application will be further described below in conjunction with specific examples.

[0051] The raw materials and auxiliary agents used in the following examples and comparative examples are commercially available products. The reaction of the present application is an organic synthesis reaction, and the raw materials used in each step of the reaction are theoretically reacted according to the molar ratio of the reaction formula, or some excess reactants are used in order to complete the reaction, so the reaction molar ratio of each step of the present application is not specifically limited.

[0052] The negative pressure system in the high vacuum HCl removal method described in the following examples is composed of a 1000 mL constant pressure funnel, a 120 cm spike fractionating column, a 1000 mL three-necked flask, a Y-shaped tube, and a silica gel hose and a water circulating vacuum pump. The entire system is closed and forms a vacuum state, which is controlled by the following steps: the 1000 mL constant pressure funnel is filled with clean water, the water flow rate is controlled slowly by the constant pressure funnel cock valve, the water droplets pass through the spike fractionating column from top to bottom, the HCl gas passes through the spike fractionating column from bottom to top, the water absorbs HCl, and the absorption liquid is collected in the flask connected at the bottom of the spike fractionating column. The circulating water in the circulating vacuum pump further absorbs a small amount of HCl that is not absorbed in the spike fractionating column.

[0053] The traditional content detection of diisooctyl phosphite adopts acid-base titration method, but when diisooctyl phosphite contains monoester and triester, because the molecules contain -OH, all of them are assumed to be diisooctyl phosphite for content calculation during titration, resulting in inaccurate results. In the present application, nuclear magnetic resonance and gas chromatography are used as detection equipment to reduce errors caused by inaccurate detection methods. According to the analysis of the obtained diisooctyl phosphite by nuclear magnetic resonance (P spectrum, H spectrum) and GC, it is found that during the alkali neutralization process, diisooctyl phosphite is hydrolyzed under acidic and basic conditions, resulting in impurities of monoester in diisooctyl phosphite, accounting for 2%-4% of the total content. At the same time, due to the high boiling point of monoester, it is always retained in the organic phase, ultimately leading to the reduction of P507 product quality and affecting its extraction separation capacity.

[0054] The standard sample of diisooctyl phosphite used in the following examples and comparative examples is a commercially available standard sample, and the P spectrum is calibrated to have a content of 96%. The yield is obtained by actual yield / theoretical yield x 100%.

[0055] Example 1

[0056] The preparation method of the diisooctyl phosphite intermediate includes the following steps:

[0057] (1) Accurately measure 1.0 mol of PCl3 and place it in a 250 mL constant pressure funnel, measure 3.1 mol of isooctanol and place it in a 1000 mL four-hole flask, dropwise add phosphorus trichloride to isooctanol in a liquid underflow manner, control the dropwise adding speed to be 1.0 mL / min, and add an ice water bath to keep the liquid temperature in the flask at 20°C, at the same time, open the water circulating vacuum pump to control the pressure at-0.020 MPa during the dropwise adding process, during the vacuum extraction process, slowly drop water into the constant pressure funnel on the HCl absorption device, collect the absorption liquid in the bottom flask, and detect the acidity, keep the pressure unchanged and the temperature at 20°C for 1.5 h to ensure that the materials are fully reacted, and part of the HCl in the obtained diisooctyl phosphite mixture is still dissolved therein.

[0058] (2) The diisooctyl phosphite mixture is deacidified by gas phase ammonia neutralization: the diisooctyl phosphite mixture is placed in a four-hole flask, the mixed gas of ammonia and nitrogen with a volume ratio of 1:9 is controlled by a pressure regulator to have a gas flow of 1000 mL / min, in order to make the ammonia and HCl fully react, the multi-hole pipe is connected to the bottom of the four-hole flask, and under the condition of stirring, the pH of the oil phase is detected by 5.0-9.0 pH test paper, and according to the color of the test paper, it is preliminarily judged to be above 7, and then the gas supply is stopped, and then a positive pressure type filter device (filter medium is 108C type encryption filter cloth) is used to filter out solid NH4Cl, if the solution is not clear, repeat the filtration operation until the acidity is below 3.33 mg NaOH / g, and the deacidified diisooctyl phosphite mixture is obtained.

[0059] (3) Distill the deacidified diisooctyl phosphite mixture: the mixture is loaded into a distillation flask, under the condition of-0.095 MPa, first slowly heat to 120°C at a speed of 2.0°C / min, and then continue to heat to 150°C for distillation after the chloroisoctane is discharged, collect the chloroisoctane (the content of chloroisoctane is 88.4%, isooctanol is 11.6%, and the yield of chloroisoctane is 95.7%), separate the two, collect the diisooctyl phosphite, and detect the content of the diisooctyl phosphite by gas chromatography, which is 97.2%, and the yield is 96.1%.

[0060] a, the diisooctyl phosphite prepared above is detected by nuclear magnetic resonance P spectrum, and the nuclear magnetic resonance P spectrum is as followsFigure 1 As shown, the NMR P-spectrum of the standard sample of diisooctyl phosphite used is as follows. Figure 2 As shown, the NMR data comparison data are shown in Table 1.

[0061] Table 1 Comparison of P-spectrum NMR data

[0062]

[0063] As can be seen from Table 1 above, the diisooctyl phosphite obtained by the present invention after deacidification by gas-phase ammonia neutralization contains a small amount of monoesters and has no other impurities, and has high purity, compared with the standard sample of diisooctyl phosphite.

[0064] b. The prepared diisooctyl phosphite was subjected to NMR 1H2 spectra, and the NMR 1H2 spectrum is shown below. Figure 3 As shown in Table 2, the NMR 1H-spectrum data of the standard sample of diisooctyl phosphite used, the theoretical prediction data, and the actual detection data of the example sample are compared with those of the example sample.

[0065] Table 2. Data results of nuclear magnetic resonance H-spectroscopy

[0066]

[0067] As can be seen from the comparison in Table 2 above, the peak area integral ratios of the H spectrum of the diisooctyl phosphite prepared in this embodiment are all within the range of theoretical prediction and standard sample, without significant deviation. Therefore, no other impurities were introduced into the synthesis of the diisooctyl phosphite of this invention, nor were any other groups introduced onto P.

[0068] c. The diisooctyl phosphite prepared above was analyzed by gas chromatography. The internal standard curve of the gas chromatography used is as follows: Figure 4 As shown, the internal standard curve is y = 3.0868x + 0.051, R0 2 =0.9693, where the gas phase detection data and the gas chromatographic data of the standard sample of diisooctyl phosphite are shown in Table 3.

[0069] Table 3 Gas Chromatography Data

[0070]

[0071] The product quality of diisooctyl phosphite obtained from the sample of Example 1 in Table 3 is higher than that of the standard sample of diisooctyl phosphite, because the mass percentage of the standard sample of diisooctyl phosphite is 96.0%; in addition, when the working curve is established, the fitting degree is slightly poor, so that the percentage of the experimental sample exceeds 100, but it does not affect the judgment of the quality of the phosphite ester. According to the data analysis of the nuclear magnetic P spectrum and H spectrum, it can be known that the diisooctyl phosphite obtained under the conditions of Example 1 is superior to the standard sample in purity and percentage.

[0072] Example 2

[0073] The preparation method of the diisooctyl phosphite intermediate comprises the following steps:

[0074] (1) Accurately take 1.0 mol of PCl3 and place it in a 250 mL constant pressure funnel, take 3.1 mol of isooctanol and place it in a 1000 mL four-hole flask, add phosphorus trichloride to isooctanol by liquid dropwise, control the dropwise speed to be 1.5 mL / min, and add an ice water bath to keep the liquid temperature in the flask at 25°C, at the same time, open the water circulating vacuum pump to control the pressure at-0.030 MPa during the dropwise process, during the vacuum process, slowly drop water into the constant pressure funnel on the HCl absorption device, collect the absorption liquid in the bottom flask, and detect the acidity, keep the pressure unchanged and the temperature at 25°C for 1 h to ensure that the materials are fully reacted, and part of HCl is still dissolved in the obtained diisooctyl phosphite mixture.

[0075] (2) The diisooctyl phosphite mixture is deacidified by gas phase ammonia neutralization method: the diisooctyl phosphite mixture is placed in a four-hole flask, the mixed gas of ammonia and nitrogen with a volume ratio of 2:8 is controlled by a pressure regulator to have a gas flow of 800 mL / min, in order to make the ammonia and HCl fully react, the multi-hole pipe is connected to the bottom of the four-hole flask, and the pH of the oil phase is detected by 5.0-9.0 pH test paper under stirring, and the color of the test paper is preliminarily judged to be more than 7, then the gas supply is stopped, and a positive pressure filter device (filter medium is 108C type encryption filter cloth) is used to filter out solid NH4Cl, if the solution is not clear, repeat the filtration operation until the acidity is less than 3.33 mg NaOH / g, and the deacidified diisooctyl phosphite mixture is obtained.

[0076] (3) Distillation of the deacidified diisooctyl phosphite mixture solution: The mixture was loaded into a distillation flask, and under the condition of -0.095 MPa, it was slowly heated to 110°C at a rate of 3.0°C / min, and after the chloroiso-octane was discharged, it was continuously heated to 130°C for distillation. The chloroiso-octane was collected (the content of chloroiso-octane was 87.4%, and the content of iso-octanol was 12.6%, and the yield of chloroiso-octane was calculated to be 94.5%), and after the two were separated, the diisooctyl phosphite was collected. The content of diisooctyl phosphite was detected by gas chromatography to be 96.8%, and the yield was calculated to be 95.1%.

[0077] Example 3

[0078] The preparation method of the diisooctyl phosphite intermediate comprises the following steps:

[0079] (1) 1.0 mol of PCl3 was accurately measured and placed in a 250 mL constant pressure funnel, and 3.1 mol of iso-octanol was measured and placed in a 1000 mL four-hole flask. The phosphorus trichloride was added dropwise to the iso-octanol by liquid underflow, the dropping speed was controlled to be 1.0 mL / min, an ice water bath was added to maintain the liquid temperature in the flask at 20°C, and a water circulating vacuum pump was started to control the pressure at -0.020 MPa during the dropping process. During the vacuum process, water was slowly added to the constant pressure funnel on the HCl absorption device, and the absorption liquid was collected in the bottom flask and the acidity was detected. The pressure was kept constant, and the temperature was kept at 20°C for 1.5 h to ensure that the materials were fully reacted. Part of the HCl in the obtained diisooctyl phosphite mixture was still dissolved therein.

[0080] (2) The diisooctyl phosphite mixture was deacidified by high vacuum: the diisooctyl phosphite mixture was heated to 65°C and transferred to a negative pressure system. The dropping speed was controlled to be 3.5 mL / min by a constant pressure funnel under the condition of -0.090 MPa, and the liquid was dropped through a thorn-shaped fractionating column with a temperature of 65°C. Until the acidity was less than 3.33 mg NaOH / g, the deacidified diisooctyl phosphite mixture was obtained.

[0081] (3) Distillation of the deacidified diisooctyl phosphite mixture solution: The mixture was loaded into a distillation flask, and under the condition of -0.095 MPa, it was slowly heated to 120°C at a rate of 3.0°C / min, and after the chloroiso-octane was discharged, it was continuously heated to 130°C for distillation. The chloroiso-octane was collected (the content of chloroiso-octane was 89.3%, and the content of iso-octanol was 10.7%, and the yield of chloroiso-octane was calculated to be 96.8%), and after the two were separated, the diisooctyl phosphite was collected. The content of diisooctyl phosphite was detected by gas chromatography to be 97.3%, and the yield was calculated to be 96.9%.

[0082] The diisooctyl phosphite prepared above was detected by nuclear magnetic resonance P spectrum, and the nuclear magnetic resonance P spectrum diagram was as followsFigure 5 The nuclear magnetic data are shown in Table 4.

[0083] Table 4 Nuclear magnetic resonance P spectrum data table

[0084]

[0085] According to the data in Table 4 above, compared with the standard sample data in Table 1, the nuclear magnetic P spectrum of the diisooctyl phosphite sample prepared in the embodiment has an additional signal peak in the peak range of 10.96-9.41, with a percentage content of 1%, and compared with the nuclear magnetic P spectrum of the standard sample, there is no unknown impurity in the peak range of 8.43-6.92. Therefore, the content and purity of the diisooctyl phosphite sample prepared in the embodiment are equivalent to those of the standard sample.

[0086] Example 4

[0087] The preparation method of the diisooctyl phosphite intermediate comprises the following steps:

[0088] (1) Accurately take 1.0 mol of PCl3 and place it in a 250 mL constant pressure funnel, and take 3.1 mol of isooctanol and place it in a 1000 mL four-hole flask. The phosphorus trichloride is added dropwise under the liquid, and is added to the isooctanol for reaction. The dropwise adding speed is controlled at 1.5 mL / min, and an ice water bath is additionally provided to maintain the liquid temperature in the flask at 25°C. At the same time, a water circulating vacuum pump is started to control the pressure at-0.030 MPa during the dropwise adding process. During the vacuum extraction process, water is slowly added to the constant pressure funnel on the HCl absorption device, and the absorption liquid is collected in the bottom flask and the acidity is detected. The pressure is kept constant, and the temperature is kept at 25°C for 1 h to ensure that the materials are fully reacted. The obtained diisooctyl phosphite mixture still has part of HCl dissolved therein;

[0089] (2) The diisooctyl phosphite mixture is subjected to high vacuum HCl removal: the diisooctyl phosphite mixture is heated to 55°C and transferred to a negative pressure system. The dropwise adding speed is controlled at 4.5 mL / min by the constant pressure funnel under the condition of-0.095 MPa, and the liquid is dropped through the thorn-shaped fractionating column, which is kept at 55°C. Until the acidity is less than 3.33 mg NaOH / g, the diisooctyl phosphite mixture after acid removal is obtained.

[0090] (3) Distillation of the mixed solution of diisooctyl phosphite after acid removal: The mixed solution was loaded into a distillation flask, and under the condition of -0.095 MPa, the temperature was slowly increased to 120°C at a rate of 2.0°C / min, and after the chloroiso-octane was discharged, the temperature was continuously increased to 150°C for distillation. The chloroiso-octane was collected (the content of chloroiso-octane was 88.5% and the content of iso-octanol was 11.5%, and the yield of chloroiso-octane was calculated to be 95.8%), and after separation, diisooctyl phosphite was collected, and the content of diisooctyl phosphite was detected by gas chromatography to be 97.5%, and the yield was calculated to be 96.3%.

[0091] Example 5

[0092] P507 was prepared using the diisooctyl phosphite intermediate prepared in Example 1, including the following steps:

[0093] (1) Preparation of sodium iso-octylate: 586 g (4.5 mol) of iso-octanol was accurately weighed into a 1000 mL flask, the heating jacket was opened, and the liquid phase was heated to 60°C. 64.5 g of 1.61 mol of solid NaOH was added into the flask at one time, the liquid phase was heated to 140°C at a rate of 2.0°C / min, and the temperature was maintained for 3 h. During the experiment, the change in the state of the solid NaOH and the time node at which the solid NaOH disappeared were recorded. After the temperature was maintained, the heating jacket was removed, and the mixed liquid was cooled to the point at which the base was caked. After the solid base was dissolved by heating, it was transferred out, and the alkalinity was detected. The liquid phase was transferred to a four-necked flask, the heating jacket was opened, and the temperature was slowly increased. The final heating temperature was controlled at 140°C. After distillation, the water content of iso-octanol was detected. The remaining amount of base in the iso-octanol was detected by gas chromatography to be 0.25 mg NaOH / g, and the sodium iso-octylate content was 22%.

[0094] (2) Condensation of diisooctyl phosphite: 1 mol of the diisooctyl phosphite intermediate prepared in Example 1 (actual effective amount 306.4 g) and 1.03 mol of sodium iso-octylate (actual effective amount 156.56 g) prepared in step (1) were accurately weighed and added into a 2000 mL four-necked flask at one time. The electric heating jacket was opened, and the vacuum pump was opened. The temperature was increased to 150°C, and the distillation time was 2 h. Iso-octanol was distilled off, and the distillation device was removed. 2.2 mol of chloroiso-octane collected in Example 1 was added into the flask at one time. The flask was provided with a reflux device, and the temperature was increased to 170°C and controlled (pay attention to the boiling). The temperature was maintained at 190°C for 3 h. After the temperature was maintained, the temperature was decreased to 80°C for distillation. The reflux device was replaced with a distillation device, and chloroiso-octane was distilled off.

[0095] The obtained material was cooled, 200 mL of pure water was added to dissolve NaCl in the material, and the material was transferred to a 1000 mL conical funnel, and phase separation was carried out. After the water phase was discharged, the oil phase was transferred to a 1000 mL four-hole flask, and water and the front fraction were distilled off. The collection flask was switched, and diisooctyl isooctyl phosphonate was refined and distilled. The temperature was 240°C, and the distillation was stopped when no material was discharged. Diisooctyl isooctyl phosphonate was obtained, and the content was 95.2%.

[0096] (3) Preparation of P507 sodium salt: A prepared 1.6 mol mass concentration 48% sodium hydroxide solution and 1.0 mol diisooctyl isooctyl phosphonate were added to a 1000 mL four-hole flask, stirring was started, and the material in the flask was heated. The distillation condenser was opened, and the temperature was slowly increased. Isooctanol was distilled at normal pressure. After 2.5 h, the liquid temperature was increased to 120°C, and then the vacuum system was started. 50% of the isooctanol was distilled off, and the remaining isooctanol was used as a solvent to prevent the material in the flask from being too viscous. At this time, the stirring should be stopped in time.

[0097] After the distillation of isooctanol was completed, the heating was stopped, the vacuum was closed, 200 mL of water was added to the flask to dissolve the material, and the stirring was started at 1000 r / min until the dissolution was completed. After the solid phase in the flask was completely dissolved, the stirring was stopped, and the material was transferred to a 1000 mL conical flask. After standing, the water phase was discharged, and P507 sodium salt was obtained.

[0098] (4) The P507 sodium salt was transferred to a four-hole flask, 1.0 mol of hydrochloric acid (mass concentration 36%) was added to acidify the oil phase to pH 1.2, and then the acid water was discharged. Water was added and stirred to wash the water, so that the final pH of the P507 oil phase was 4. Finally, the water washing was completed, the P507 was transferred to a four-hole flask, the stirring and heating were started, the condenser was opened, and the water and isooctanol were distilled off under the condition of -0.09 MPa vacuum at 90°C (gas phase temperature). When the liquid temperature reached 145°C, the water ring vacuum pump was switched to the rotary vane vacuum pump. When the liquid temperature was 180°C, the vacuum was -0.1 MPa, the fraction was significantly reduced, and the gas temperature started to drop. The distillation process of isooctanol was completed, the heating was stopped, the vacuum pump was stopped, and P507 was obtained. The content was detected by the acid-base titration method in the industry, which was 97.4%, and the yield was 86.7%.

[0099] Example 6

[0100] P507 was prepared using the diisooctyl phosphite intermediate prepared in Example 3, including the following steps:

[0101] (1) Preparation of sodium iso-octanol: accurately weigh 586 g (4.5 mol) of iso-octanol and put it into a 1000 mL flask, open the heating jacket, heat the liquid phase to 70°C, weigh 64.5 g of 1.61 mol of solid NaOH and add it into the flask at one time, heat the liquid phase to 150°C at a rate of 3.0°C / min, keep the temperature for 3 h, record the change of the state of the solid NaOH and the time node at which the solid NaOH disappears during the experiment, after the temperature keeping, remove the heating jacket, cool the mixed liquid to the point at which the NaOH is solidified, dissolve the solid NaOH by heating and then transfer it out, detect the alkalinity, transfer the liquid phase into a four-hole flask, open the heating jacket, slowly heat, and finally control the heating temperature at 140°C, after the distillation, detect the water content of the iso-octanol, by gas chromatography, the residual amount of NaOH in the iso-octanol is 0.31 mg NaOH / g, and the content of sodium iso-octanol is 23.5%.

[0102] (2) Condensation of diisooctyl iso-octyl phosphonate: accurately weigh 1 mol of the diisooctyl phosphite intermediate prepared in Example 3 (306.4 g of the effective amount), weigh 1.03 mol of sodium iso-octanol prepared in step (1) (156.56 g of the effective amount), add them into a 2000 mL four-hole flask at one time, open the electric heating jacket and the vacuum pump, heat to 140°C, distill for 2 h to distill out the iso-octanol, remove the distillation device, weigh the chloroiso-octane (2.2 mol) collected in Example 3 and add it into the flask at one time, add a reflux device to the flask, heat to 170°C and then control the temperature (pay attention to the bumping), keep the temperature at 180°C for 4 h, after the temperature keeping, cool to 90°C, change the reflux device into a distillation device, and distill out the chloroiso-octane.

[0103] After cooling the obtained material, add 200 mL of pure water to dissolve the NaCl in the material, transfer it into a 1000 mL conical funnel, separate the phases by standing, discharge the water phase, and then transfer the oil phase into a 1000 mL four-hole flask, distill out the water and the front fraction, switch the collection flask, and then perform the fine distillation of diisooctyl iso-octyl phosphonate at a temperature of 230°C until no material is distilled out, to obtain diisooctyl iso-octyl phosphonate, and the content thereof is 94.8%.

[0104] (3) Preparation of P507 sodium salt: add the prepared 1.6 mol of 46% sodium hydroxide solution and 1.0 mol of diisooctyl iso-octyl phosphonate into a 1000 mL four-hole flask, open the stirring device, and heat the material in the flask. Open the distillation condenser, slowly heat, and distill out the iso-octanol under normal pressure, the liquid temperature is raised to 130°C after 1.5 h, then open the vacuum system, distill out 50% of the iso-octanol, and the remaining iso-octanol is used as a solvent to prevent the material in the flask from being too viscous, at this time, the stirring should be stopped in time.

[0105] After the distillation of isooctanol is completed, stop heating, turn off the vacuum, add 200 mL of water into the flask to dissolve, confirm that the stirring is at 500 r / min until the complete dissolution, start the stirring, make the solid phase in the flask completely dissolved, then stop the stirring, transfer to a 1000 mL conical flask, and after standing, discharge the water phase to obtain the P507 sodium salt.

[0106] (4) Transfer the P507 sodium salt into a four-necked flask, add 1.0 mol of hydrochloric acid (mass concentration 34%) to acidify the oil phase to pH 0.8, then discharge the acid water, add water to stir and wash, so that the final pH of the P507 oil phase is 5, finally, transfer the P507 to the four-necked flask after the water washing is completed, start the stirring and heating, open the condenser, and distill water and isooctanol under the condition of -0.09 MPa vacuum at 90°C (gas phase temperature), when the liquid temperature reaches 145°C, switch the water ring vacuum pump to the rotary vane vacuum pump, when the liquid temperature is 180°C, the vacuum is -0.1 MPa, the distillate is significantly reduced, and the gas temperature starts to drop, the distillation process of isooctanol is completed, stop heating, vent, stop the condenser and vacuum pump, and obtain P507, the content of which is 96.5%, and the yield thereof is 85.8%.

[0107] Comparative Example 1

[0108] A preparation method of a diisooctyl phosphite intermediate, comprising the following steps:

[0109] (1) Accurately take 1.0 mol of PCl3 and place it in a 250 mL constant pressure funnel, take 3.1 mol of isooctanol and place it in a 1000 mL four-necked flask, drop the phosphorus trichloride into the isooctanol by liquid underflow dropwise, control the dropwise speed to be 1.0 mL / min, and add an ice water bath to keep the liquid temperature in the flask at 20°C, at the same time, start the water circulating vacuum pump to control the pressure at -0.020 MPa during the dropwise process, slowly drop water into the constant pressure funnel on the HCl absorption device during the vacuum process, collect the absorption liquid in the bottom flask, and detect the acidity, keep the pressure unchanged and the temperature at 20°C for 1.5 h to ensure that the materials are fully reacted, and part of the HCl is still dissolved in the diisooctyl phosphite mixture obtained.

[0110] (2) Alkaline neutralization method for removing acid from the diisooctyl phosphite mixture: transfer the diisooctyl phosphite mixture to a 1000 mL conical funnel, first wash the material with pure water to ensure that most of the HCl is dissolved in the water, discharge the water phase from the bottom, add a 10% NaOH solution to the conical funnel, adjust to neutral, then wash the mixture with water three times, separate the oil phase from the aqueous solution, until the acidity is less than 3.33 mg NaOH / g, and obtain the diisooctyl phosphite mixture after the acid is removed.

[0111] (3) Distillation of the deacidified diisooctyl phosphite mixed solution: The mixed solution was loaded into a distillation flask, and under the condition of -0.095 MPa, the temperature was first slowly increased to 120°C at a rate of 2.0°C / min, and after the chlorinated isooctane was discharged, the temperature was continuously increased to 150°C for distillation. The chlorinated isooctane was collected (the content of chlorinated isooctane was 86.2%, the content of isooctanol was 13.8%, and the yield was 93%), and after separation, the diisooctyl phosphite was collected. The content of diisooctyl phosphite was 88.5% as detected by gas chromatography, and the yield was 93%.

[0112] The diisooctyl phosphite prepared above was detected by nuclear magnetic resonance P spectrum, and the nuclear magnetic resonance P spectrum chart is shown in Figure 6 , and the nuclear magnetic data is shown in Table 5.

[0113] Table 5 Nuclear magnetic resonance P spectrum data table

[0114]

[0115] According to the data in Table 5 above and the standard sample data in Table 1, the nuclear magnetic P spectrum of the diisooctyl phosphite sample prepared in the above comparative example has additional signal peaks in the peak range of 10.96-9.41 and 8.43-6.92, with a percentage content of 2% and 1%. Compared with the nuclear magnetic P spectrum of the standard sample, the content of the mono-ester is the same as 3%. The content and purity of the diisooctyl phosphite sample prepared in the above comparative example are higher than those of the standard sample in terms of impurity content and type.

[0116] Comparative Example 2

[0117] A method for preparing a diisooctyl phosphite intermediate, comprising the following steps:

[0118] (1) Accurately measure 1.0 mol of PCl3 and place it in a 250 mL constant pressure funnel, and measure 3.1 mol of isooctanol and place it in a 1000 mL four-hole flask. PCl3 is directly added to the liquid surface of isooctanol, the dropping speed is controlled at 1.0 mL / min, an ice water bath is added to maintain the liquid temperature in the flask at 20°C, and a water circulating vacuum pump is started to control the pressure at -0.020 MPa during the dropping process. During the vacuum process, water is slowly added to the constant pressure funnel on the HCl absorption device, and the absorption liquid is collected in the bottom flask and the acidity is detected. The pressure remains unchanged and the temperature is kept at 20°C for 1.5 h to ensure that the materials are fully reacted. Part of the HCl is still dissolved in the obtained diisooctyl phosphite mixture.

[0119] (2) The diisooctyl phosphite mixture is deacidified by gas phase ammonia neutralization: The diisooctyl phosphite mixture is placed in a four-hole flask, and a mixture of ammonia gas and nitrogen gas with a volume ratio of 1:9 is passed through a pressure regulator to control the gas flow at 1000 mL / min. In order to fully react the ammonia gas with HCl, the mixture is introduced into the bottom of the four-hole flask through a porous pipe under stirring. The pH of the oil phase is detected by 5.0-9.0 pH test paper, and the color of the test paper is preliminarily judged to be above 7. The gas supply is stopped, and then a positive pressure filtration device (filter medium is 108C type encryption filter cloth) is used to filter out solid NH4Cl. If the solution is not clear, repeat the filtration operation until the acidity is below 3.33 mg NaOH / g. The deacidified diisooctyl phosphite mixture is obtained.

[0120] (3) The deacidified diisooctyl phosphite mixture is distilled: The mixture is placed in a distillation flask, and under the condition of -0.095 MPa, it is slowly heated to 120°C at a speed of 2.0°C / min. After the chlorinated isooctane is discharged, the temperature is continuously increased to 150°C for distillation. The chlorinated isooctane is collected (the content of chlorinated isooctane is 83.7%, the content of isooctanol is 16.3%, and the yield of chlorinated isooctane is 90.0%). After separation, the diisooctyl phosphite is collected, and the content is detected by gas chromatography to be 96.1%, and the yield is calculated to be 90.4%.

Claims

1. A process for the preparation of diisooctyl phosphite intermediate, characterized by, The method comprises the following steps: The phosphorus trichloride is added dropwise into isooctanol to react, the dropping speed is controlled to be 1.0 mL / min-1.5 mL / min, the dropping pressure is controlled to be-0.020 MPa--0.030 MPa, the reaction temperature is controlled to be 20-25 ℃, the reaction time is controlled to be 1-1.5 h, and the diisooctyl phosphite mixture is obtained; the diisooctyl phosphite mixture is treated by the gas-phase ammonia neutralization method or the high-vacuum HCl removal method to remove impurities, the acidity is detected to be less than or equal to 3.33 mg NaOH / g, the chlorinated isooctane is distilled out and collected to obtain the chlorinated isooctane by-product, and finally the diisooctyl phosphite is obtained; The specific steps of the gas-phase ammonia neutralization method are as follows: the mixed gas of ammonia and nitrogen is introduced into the diisooctyl phosphite mixture, the volume ratio of the ammonia and the nitrogen is 1:9-2:8, and the mixture is stirred, the gas flow is controlled to be 800-1000 mL / min until the acidity is less than or equal to 3.33 mg NaOH / g, then the mixture is filtered until the filtrate is clear, and the acid-removed mixture is obtained; The specific steps of the high-vacuum HCl removal method are as follows: the temperature of the diisooctyl phosphite mixture is controlled to be 55-65 ℃, the dropping speed is controlled to be 3.0 mL / min-4.5 mL / min by using a negative pressure system at a pressure of-0.090 MPa--0.095 MPa, and the mixture is dropped through a thorn-shaped fractionating column until the acidity is less than or equal to 3.33 mg NaOH / g, and the acid-removed mixture is obtained.

2. The process for the preparation of diisooctyl phosphite intermediate as claimed in claim 1 wherein: The negative pressure system comprises a constant-pressure funnel, a thorn-shaped fractionating column and a 2XZ-2 rotary vane vacuum pump.

3. The process for the preparation of diisooctyl phosphite intermediate as claimed in claim 1 wherein: The distillation is carried out at a pressure of-0.095 MPa, the temperature is first increased to 110-120 ℃ at a speed of 2.0-3.0 ℃ / min, then the temperature is continuously increased to 130-150 ℃ after the chlorinated isooctane is discharged, and the distillation is stopped until no chlorinated isooctane is distilled out.

4. The process for the preparation of diisooctyl phosphite intermediate as claimed in claim 1 wherein: The reaction temperature is controlled by an ice-water bath during the reaction of the diisooctyl phosphite mixture, and the hydrogen chloride gas generated during the reaction is absorbed by a hydrogen chloride absorption device.

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