A purification process of hydroxylamine aqueous solution based on combination of ion exchange membrane and adsorption resin

Abstract

The application relates to a hydroxylamine aqueous solution purification process based on the combination of ion exchange membranes and adsorption resins, and relates to the hydroxylamine preparation technical field. Impurity-containing hydroxylamine aqueous solution is removed of impurities by passing through a strong-acid cation exchange resin column and a strong-alkali anion exchange resin column; the ion-exchanged hydroxylamine solution is filtered through a benzocyclobutene high-temperature sintering modified membrane to further improve the purity of the solution; the solution filtered through the modified membrane is introduced into an ion exchange membrane electrodialysis device for deep impurity removal; the benzocyclobutene high-temperature sintering modified membrane is prepared by using alumina ceramic powder, titanium dioxide, 4-vinyl benzocyclobutene, dibenzoyl peroxide and polyvinyl alcohol adhesive; the application can significantly reduce the impurity content and realize efficient separation and purification of hydroxylamine.

Description

Technical Field

[0001] This invention relates to the field of hydroxylamine preparation technology, and in particular to a purification process for hydroxylamine aqueous solution based on the combined use of ion exchange membrane and adsorption resin. Background Technology

[0002] Hydroxylamine has a wide range of applications in many industries, such as in the pharmaceutical industry for the preparation of specialty drugs and in the microelectronics industry for photoresist stripping compositions. In these applications, the purity requirements for hydroxylamine products are extremely high, especially the strict control of the content of metal cations and anions.

[0003] Chinese Patent CN1102531C: A method for producing an aqueous solution of free hydroxylamine. The solution obtained by treating hydroxylamine salts with alkali is then treated with water or steam at a temperature ≥80°C, causing the solution to separate into an aqueous hydroxylamine fraction and a salt-containing fraction.

[0004] Chinese Patent CN119528096B: Belongs to the field of chemical separation and purification technology, specifically relating to a method for removing impurities from an aqueous hydroxylamine solution. The method for removing impurities from an aqueous hydroxylamine solution provided by this invention includes the following steps: mixing an aqueous hydroxylamine solution with an alkaline compound, allowing it to settle, and then separating the solid and liquid phases to obtain the liquid phase; the alkaline compound includes barium hydroxide or calcium hydroxide; passing the liquid phase through an ion exchange column for ion exchange to obtain a purified aqueous hydroxylamine solution; the resin in the ion exchange column is a resin containing phenolic hydroxyl groups.

[0005] The patents and existing technologies mentioned above utilize ion exchange technology as a common method for purifying hydroxylamine. However, ion exchange processes have limited ability to remove organic impurities from aqueous hydroxylamine solutions, and the presence of these impurities may affect the performance of hydroxylamine in subsequent applications. Therefore, developing a deep purification process that can effectively remove various impurities from aqueous hydroxylamine solutions while ensuring process safety and stability is of significant practical importance. Summary of the Invention

[0006] To address the aforementioned problems, this invention provides a purification process based on the combined use of an ion exchange membrane and an adsorption resin with an aqueous hydroxylamine solution. The operation steps are as follows:

[0007] S1 Pretreatment: The strongly acidic cation exchange resin column is pretreated with dilute hydrochloric acid solution; the strongly basic anion exchange resin column is pretreated with sodium hydroxide solution; the hydroxylamine aqueous solution is filtered to remove insoluble impurities.

[0008] S2 Cation Exchange: A hydroxylamine aqueous solution containing impurities is passed through a strongly acidic cation exchange resin column at a flow rate of 3-4 BV / h (BV is the resin bed volume). During this process, the cationic impurities in the solution undergo an exchange reaction with the hydrogen ions on the strongly acidic cation exchange resin, thereby being adsorbed onto the resin and achieving the removal of cationic impurities.

[0009] S3 Anion Exchange: The hydroxylamine solution after cation exchange is passed through a strongly basic anion exchange resin column at a flow rate of 2-3 BV / h; during this process, the anionic impurities in the solution undergo an exchange reaction with the hydroxide ions on the strongly basic anion exchange resin and are adsorbed onto the resin, thus removing the anionic impurities.

[0010] S4 purification: The hydroxylamine solution after anion exchange is filtered through a benzocyclobutene high-temperature sintered modified membrane to further improve the purity of the solution.

[0011] S5 Electrodialysis for Deep Impurity Removal: The solution filtered through the modified membrane is introduced into an ion exchange membrane electrodialysis device for deep impurity removal. Under the action of an electric field, ions in the solution will migrate directionally through the ion exchange membrane, with cations moving towards the cathode and anions moving towards the anode, thereby achieving deep removal of trace ions.

[0012] As a preferred embodiment of the present invention, the mass percentage of the dilute hydrochloric acid solution of S1 is 5%.

[0013] As a preferred embodiment of the present invention, the sodium hydroxide solution of S1 has a mass percentage of 3%.

[0014] As a preferred embodiment of the present invention, the S1 strong acid cation exchange resin column is one of the following: 001×7 strong acid styrene-based cation exchange resin column, 001×4 strong acid styrene-based cation exchange resin column, and 001×12 strong acid styrene-based cation exchange resin column.

[0015] As a preferred embodiment of the present invention, the S1 strong basic anion exchange resin column is one of the following: D201 macroporous strong basic styrene-based anion exchange resin column, D202 macroporous II strong basic styrene-based anion exchange resin column, and D-72A styrene-based macroporous strong basic anion exchange resin column.

[0016] As a preferred embodiment of the present invention, the voltage of the S5 electrodialysis is 15-20V, and the current density is 20-25A / m. 2 .

[0017] As a preferred embodiment of the present invention, the method for preparing the benzocyclobutene high-temperature sintering modified membrane is as follows:

[0018] A1 Granulation: 80-100 parts of alumina ceramic powder and 5-15 parts of titanium dioxide are sintered at 1200-1400℃ for 2-4 hours, cooled, and then 1-3 parts of 4-vinylbenzocyclobutene and 0.05-0.1 parts of benzoyl peroxide are added and mixed. The mixture is ball-milled at 200-400 rpm for 4-8 hours and then spray-dried to granulate.

[0019] A2 molding: The granulated powder is pressed into a film preform by molding.

[0020] A3 Sintering: The preform is sintered at 800-1000℃ for 2-4 hours to form a cross-linked network between the polymer and the ceramic, thus obtaining a benzocyclobutene high-temperature sintered modified membrane.

[0021] As a preferred embodiment of the present invention, 3-5 parts of polyvinyl alcohol binder and 30-50 parts of deionized water are added during the A1 granulation process.

[0022] As a preferred embodiment of the present invention, the A2 molding pressure is 10-20 MPa.

[0023] As a preferred embodiment of the present invention, the sintering temperature of A3 is 800-1000℃ and the time is 2-4h.

[0024] Reaction mechanism:

[0025] 1. Granulation stage: Alumina ceramic powder and TiO2 are sintered at high temperature to form a ceramic skeleton structure. TiO2 is uniformly dispersed to enhance the mechanical strength and surface polarity of the ceramic phase. After cooling, 4-vinylbenzocyclobutene and benzoyl peroxide are added. During ball milling, benzoyl peroxide decomposes to generate free radicals, which catalyze the four-membered ring-opening polymerization of benzocyclobutene. At the same time, the vinyl double bond participates in the cross-linking reaction to form a three-dimensional organic network. Polyvinyl alcohol binder promotes powder agglomeration, and spray drying yields granules with good flowability.

[0026] 2. Molding stage: Molding makes the particles tightly bonded, initially forming the porous structure of the membrane.

[0027] 3. Sintering stage: During the secondary sintering, the organic polymer network undergoes a condensation reaction with the hydroxyl groups on the ceramic surface (forming Si-OC bonds) to build an organic-inorganic cross-linked network; the ceramic phase is further sintered and densified, regulating the pore size distribution of the membrane, while the organic network enhances the flexibility and impact resistance of the membrane. Attached Figure Description

[0028] Figure 1 This is the infrared spectrum of an aqueous solution of hydroxylamine.

[0029] Technical effects:

[0030] The modified membrane of the present invention has the following beneficial effects:

[0031] 1. High selectivity: The organic-inorganic cross-linked network regulates the membrane pore size, and the hydroxyl groups on the TiO2 surface form hydrogen bonds with the hydroxyl groups of hydroxylamine, which synergistically achieves the sieving and adsorption separation of hydroxylamine, resulting in high purity.

[0032] 2. Strong hydrophilicity and antifouling properties: The hydrophilicity of TiO2 polar groups and organic network enhances membrane surface wettability, reduces impurity adsorption, lowers membrane fouling, and extends operating cycle.

[0033] 3. Excellent structural stability: The ceramic skeleton formed by high-temperature sintering is firmly bonded to the organic cross-linked network, resulting in high mechanical strength, excellent acid and alkali resistance and high-temperature resistance, and a long service life.

[0034] 4. Strong process adaptability: It can withstand the high-temperature operation in the purification of hydroxylamine aqueous solution, and is suitable for continuous industrial production with low energy consumption. Detailed Implementation

[0035] To further illustrate the technical means and effects adopted by the present invention to achieve the intended purpose, the following detailed description is provided in conjunction with embodiments and comparative examples:

[0036] 1. Hydroxylamine content detection: Acid-base titration method was used.

[0037] 2. Impurity content detection: Inductively coupled plasma mass spectrometry, ion chromatography, and high performance liquid chromatography were used for determination.

[0038] Example 1

[0039] A purification process based on hydroxylamine aqueous solution using a combination of ion exchange membrane and adsorption resin, comprising the following steps:

[0040] S1 Pretreatment: The strongly acidic cation exchange resin column is pretreated with dilute hydrochloric acid solution; the strongly basic anion exchange resin column is pretreated with sodium hydroxide solution; the hydroxylamine aqueous solution is filtered to remove insoluble impurities.

[0041] S2 Cation Exchange: A hydroxylamine aqueous solution containing impurities is passed through a strongly acidic cation exchange resin column at a flow rate of 3 BV / h (BV is the resin bed volume). During this process, the cationic impurities in the solution undergo an exchange reaction with the hydrogen ions on the strongly acidic cation exchange resin, thereby being adsorbed onto the resin and achieving the removal of cationic impurities.

[0042] S3 Anion Exchange: The hydroxylamine solution after cation exchange is passed through a strongly basic anion exchange resin column at a flow rate of 2 BV / h; during this process, anionic impurities in the solution undergo an exchange reaction with hydroxide ions on the strongly basic anion exchange resin and are adsorbed onto the resin, thus removing the anionic impurities.

[0043] S4 purification: The hydroxylamine solution after anion exchange is filtered through a benzocyclobutene high-temperature sintered modified membrane to further improve the purity of the solution.

[0044] S5 Electrodialysis for Deep Impurity Removal: The solution filtered through the modified membrane is introduced into an ion exchange membrane electrodialysis device for deep impurity removal. Under the action of an electric field, ions in the solution will migrate directionally through the ion exchange membrane, with cations moving towards the cathode and anions moving towards the anode, thereby achieving deep removal of trace ions.

[0045] The mass percentage of the dilute hydrochloric acid solution of S1 is 5%.

[0046] The sodium hydroxide solution of S1 has a mass percentage of 3%.

[0047] The S1 strong acid cation exchange resin column is a 001×7 strong acid styrene-based cation exchange resin column.

[0048] The S1 strong basic anion exchange resin column is a D201 macroporous strong basic styrene-based anion exchange resin column.

[0049] The S5 electrodialysis system uses a voltage of 15V and a current density of 20A / m³. 2 .

[0050] The method for preparing the benzocyclobutene high-temperature sintering modified membrane is as follows:

[0051] A1 granulation: 80g of alumina ceramic powder and 5g of titanium dioxide were sintered at 1200℃ for 2h, cooled, and then 1g of 4-vinylbenzocyclobutene and 0.05g of benzoyl peroxide were added and mixed. The mixture was ball-milled at 200rpm for 4h and then spray-dried to granulate.

[0052] A2 molding: The granulated powder is pressed into a film preform by molding.

[0053] A3 Sintering: The preform is sintered at 800℃ for 2 hours to form a cross-linked network between the polymer and the ceramic, resulting in a benzocyclobutene high-temperature sintered modified membrane.

[0054] The A1 granulation process also requires the addition of 3g of polyvinyl alcohol binder and 30g of deionized water.

[0055] The A2 molding pressure is 10 MPa.

[0056] The A3 sintering temperature is 800℃ and the time is 2h.

[0057] Example 2

[0058] A purification process based on hydroxylamine aqueous solution using a combination of ion exchange membrane and adsorption resin, comprising the following steps:

[0059] S1 Pretreatment: The strongly acidic cation exchange resin column is pretreated with dilute hydrochloric acid solution; the strongly basic anion exchange resin column is pretreated with sodium hydroxide solution; the hydroxylamine aqueous solution is filtered to remove insoluble impurities.

[0060] S2 Cation Exchange: A hydroxylamine aqueous solution containing impurities is passed through a strongly acidic cation exchange resin column at a flow rate of 3 BV / h (BV is the resin bed volume). During this process, the cationic impurities in the solution undergo an exchange reaction with the hydrogen ions on the strongly acidic cation exchange resin, thereby being adsorbed onto the resin and achieving the removal of cationic impurities.

[0061] S3 Anion Exchange: The hydroxylamine solution after cation exchange is passed through a strongly basic anion exchange resin column at a flow rate of 2 BV / h; during this process, anionic impurities in the solution undergo an exchange reaction with hydroxide ions on the strongly basic anion exchange resin and are adsorbed onto the resin, thus removing the anionic impurities.

[0062] S4 purification: The hydroxylamine solution after anion exchange is filtered through a benzocyclobutene high-temperature sintered modified membrane to further improve the purity of the solution.

[0063] S5 Electrodialysis for Deep Impurity Removal: The solution filtered through the modified membrane is introduced into an ion exchange membrane electrodialysis device for deep impurity removal. Under the action of an electric field, ions in the solution will migrate directionally through the ion exchange membrane, with cations moving towards the cathode and anions moving towards the anode, thereby achieving deep removal of trace ions.

[0064] The mass percentage of the dilute hydrochloric acid solution of S1 is 5%.

[0065] The sodium hydroxide solution of S1 has a mass percentage of 3%.

[0066] The S1 strong acid cation exchange resin column is a 001×4 strong acid styrene-based cation exchange resin column.

[0067] The S1 strong basic anion exchange resin column is a D202 macroporous II strong basic styrene-based anion exchange resin column.

[0068] The S5 electrodialysis system uses a voltage of 15V and a current density of 20A / m³. 2 .

[0069] The method for preparing the benzocyclobutene high-temperature sintering modified membrane is as follows:

[0070] A1 granulation: 85g of alumina ceramic powder and 8g of titanium dioxide were sintered at 1250℃ for 3h, cooled, and then 2g of 4-vinylbenzocyclobutene and 0.06g of benzoyl peroxide were added and mixed. The mixture was ball-milled at 300rpm for 5h and then spray-dried to granulate.

[0071] A2 molding: The granulated powder is pressed into a film preform by molding.

[0072] A3 Sintering: The preform is sintered at 850℃ for 3 hours to form a cross-linked network between the polymer and the ceramic, resulting in a benzocyclobutene high-temperature sintered modified membrane.

[0073] The A1 granulation process also requires the addition of 4g of polyvinyl alcohol binder and 35g of deionized water.

[0074] The A2 molding pressure is 15 MPa.

[0075] The A3 sintering temperature is 850℃ and the time is 3h.

[0076] Example 3

[0077] A purification process based on hydroxylamine aqueous solution using a combination of ion exchange membrane and adsorption resin, comprising the following steps:

[0078] S1 Pretreatment: The strongly acidic cation exchange resin column is pretreated with dilute hydrochloric acid solution; the strongly basic anion exchange resin column is pretreated with sodium hydroxide solution; the hydroxylamine aqueous solution is filtered to remove insoluble impurities.

[0079] S2 Cation Exchange: A hydroxylamine aqueous solution containing impurities is passed through a strongly acidic cation exchange resin column at a flow rate of 4 BV / h (BV is the resin bed volume). During this process, the cationic impurities in the solution undergo an exchange reaction with the hydrogen ions on the strongly acidic cation exchange resin, thereby being adsorbed onto the resin and achieving the removal of cationic impurities.

[0080] S3 Anion Exchange: The hydroxylamine solution after cation exchange is passed through a strong base anion exchange resin column at a flow rate of 3 BV / h; during this process, anionic impurities in the solution undergo an exchange reaction with hydroxide ions on the strong base anion exchange resin and are adsorbed onto the resin, thus removing the anionic impurities.

[0081] S4 purification: The hydroxylamine solution after anion exchange is filtered through a benzocyclobutene high-temperature sintered modified membrane to further improve the purity of the solution.

[0082] S5 Electrodialysis for Deep Impurity Removal: The solution filtered through the modified membrane is introduced into an ion exchange membrane electrodialysis device for deep impurity removal. Under the action of an electric field, ions in the solution will migrate directionally through the ion exchange membrane, with cations moving towards the cathode and anions moving towards the anode, thereby achieving deep removal of trace ions.

[0083] The mass percentage of the dilute hydrochloric acid solution of S1 is 5%.

[0084] The sodium hydroxide solution of S1 has a mass percentage of 3%.

[0085] The S1 strong acid cation exchange resin column is a 001×4 strong acid styrene-based cation exchange resin column.

[0086] The S1 strong basic anion exchange resin column is a D202 macroporous II strong basic styrene-based anion exchange resin column.

[0087] The S5 electrodialysis system uses a voltage of 20V and a current density of 25A / m. 2 .

[0088] The method for preparing the benzocyclobutene high-temperature sintering modified membrane is as follows:

[0089] A1 Granulation: 95g of alumina ceramic powder and 13g of titanium dioxide were sintered at 1350℃ for 3h, cooled, and then 2g of 4-vinylbenzocyclobutene and 0.08g of benzoyl peroxide were added and mixed. The mixture was ball-milled at 300rpm for 7h and then spray-dried to granulate.

[0090] A2 molding: The granulated powder is pressed into a film preform by molding.

[0091] A3 Sintering: The preform is sintered at 950℃ for 3 hours to form a cross-linked network between the polymer and the ceramic, resulting in a benzocyclobutene high-temperature sintered modified membrane.

[0092] The A1 granulation process also requires the addition of 4g of polyvinyl alcohol binder and 45g of deionized water.

[0093] The A2 molding pressure is 15 MPa.

[0094] The A3 sintering temperature is 950℃ and the time is 3h.

[0095] Example 4

[0096] A purification process based on hydroxylamine aqueous solution using a combination of ion exchange membrane and adsorption resin, comprising the following steps:

[0097] S1 Pretreatment: The strongly acidic cation exchange resin column is pretreated with dilute hydrochloric acid solution; the strongly basic anion exchange resin column is pretreated with sodium hydroxide solution; the hydroxylamine aqueous solution is filtered to remove insoluble impurities.

[0098] S2 Cation Exchange: A hydroxylamine aqueous solution containing impurities is passed through a strongly acidic cation exchange resin column at a flow rate of 4 BV / h (BV is the resin bed volume). During this process, the cationic impurities in the solution undergo an exchange reaction with the hydrogen ions on the strongly acidic cation exchange resin, thereby being adsorbed onto the resin and achieving the removal of cationic impurities.

[0099] S3 Anion Exchange: The hydroxylamine solution after cation exchange is passed through a strong base anion exchange resin column at a flow rate of 3 BV / h; during this process, anionic impurities in the solution undergo an exchange reaction with hydroxide ions on the strong base anion exchange resin and are adsorbed onto the resin, thus removing the anionic impurities.

[0100] S4 purification: The hydroxylamine solution after anion exchange is filtered through a benzocyclobutene high-temperature sintered modified membrane to further improve the purity of the solution.

[0101] S5 Electrodialysis for Deep Impurity Removal: The solution filtered through the modified membrane is introduced into an ion exchange membrane electrodialysis device for deep impurity removal. Under the action of an electric field, ions in the solution will migrate directionally through the ion exchange membrane, with cations moving towards the cathode and anions moving towards the anode, thereby achieving deep removal of trace ions.

[0102] The mass percentage of the dilute hydrochloric acid solution of S1 is 5%.

[0103] The sodium hydroxide solution of S1 has a mass percentage of 3%.

[0104] The S1 strong acid cation exchange resin column is a 001×12 strong acid styrene-based cation exchange resin column.

[0105] The S1 strong basic anion exchange resin column is a D-72A styrene-based macroporous strong basic anion exchange resin column.

[0106] The S5 electrodialysis system uses a voltage of 20V and a current density of 25A / m. 2 .

[0107] The method for preparing the benzocyclobutene high-temperature sintering modified membrane is as follows:

[0108] A1 granulation: 100g of alumina ceramic powder and 15g of titanium dioxide were sintered at 1400℃ for 4h, cooled, and then 3g of 4-vinylbenzocyclobutene and 0.1g of benzoyl peroxide were added and mixed. The mixture was ball-milled at 400rpm for 8h and then spray-dried to granulate.

[0109] A2 molding: The granulated powder is pressed into a film preform by molding.

[0110] A3 Sintering: The preform is sintered at 1000℃ for 4 hours to form a cross-linked network between the polymer and the ceramic, resulting in a benzocyclobutene high-temperature sintered modified membrane.

[0111] The A1 granulation process also requires the addition of 5g of polyvinyl alcohol binder and 50g of deionized water.

[0112] The A2 molding pressure is 20 MPa.

[0113] The A3 sintering temperature is 1000℃ and the time is 4h.

[0114] Comparative Example 1

[0115] A purification process based on hydroxylamine aqueous solution using a combination of ion exchange membrane and adsorption resin, comprising the following steps:

[0116] S1 Pretreatment: The strongly acidic cation exchange resin column is pretreated with dilute hydrochloric acid solution; the strongly basic anion exchange resin column is pretreated with sodium hydroxide solution; the hydroxylamine aqueous solution is filtered to remove insoluble impurities.

[0117] S2 Cation Exchange: A hydroxylamine aqueous solution containing impurities is passed through a strongly acidic cation exchange resin column at a flow rate of 3 BV / h (BV is the resin bed volume). During this process, the cationic impurities in the solution undergo an exchange reaction with the hydrogen ions on the strongly acidic cation exchange resin, thereby being adsorbed onto the resin and achieving the removal of cationic impurities.

[0118] S3 Anion Exchange: The hydroxylamine solution after cation exchange is passed through a strongly basic anion exchange resin column at a flow rate of 2 BV / h; during this process, anionic impurities in the solution undergo an exchange reaction with hydroxide ions on the strongly basic anion exchange resin and are adsorbed onto the resin, thus removing the anionic impurities.

[0119] S4 Electrodialysis for Deep Impurity Removal: The solution filtered through the modified membrane is introduced into an ion exchange membrane electrodialysis device for deep impurity removal. Under the action of an electric field, ions in the solution will migrate directionally through the ion exchange membrane, with cations moving towards the cathode and anions moving towards the anode, thereby achieving deep removal of trace ions.

[0120] The mass percentage of the dilute hydrochloric acid solution of S1 is 5%.

[0121] The sodium hydroxide solution of S1 has a mass percentage of 3%.

[0122] The S1 strong acid cation exchange resin column is a 001×7 strong acid styrene-based cation exchange resin column.

[0123] The S1 strong basic anion exchange resin column is a D201 macroporous strong basic styrene-based anion exchange resin column.

[0124] The voltage for the S4 electrodialysis is 15V, and the current density is 20A / m. 2 .

[0125] Comparative Example 2

[0126] A purification process based on hydroxylamine aqueous solution using a combination of ion exchange membrane and adsorption resin, comprising the following steps:

[0127] S1 Pretreatment: The strongly acidic cation exchange resin column is pretreated with dilute hydrochloric acid solution; the strongly basic anion exchange resin column is pretreated with sodium hydroxide solution; the hydroxylamine aqueous solution is filtered to remove insoluble impurities.

[0128] S2 Cation Exchange: A hydroxylamine aqueous solution containing impurities is passed through a strongly acidic cation exchange resin column at a flow rate of 3 BV / h (BV is the resin bed volume). During this process, the cationic impurities in the solution undergo an exchange reaction with the hydrogen ions on the strongly acidic cation exchange resin, thereby being adsorbed onto the resin and achieving the removal of cationic impurities.

[0129] S3 Anion Exchange: The hydroxylamine solution after cation exchange is passed through a strongly basic anion exchange resin column at a flow rate of 2 BV / h; during this process, anionic impurities in the solution undergo an exchange reaction with hydroxide ions on the strongly basic anion exchange resin and are adsorbed onto the resin, thus removing the anionic impurities.

[0130] S4 purification: The hydroxylamine solution after anion exchange is filtered through a benzocyclobutene high-temperature sintered modified membrane to further improve the purity of the solution.

[0131] S5 Electrodialysis for Deep Impurity Removal: The solution filtered through the modified membrane is introduced into an ion exchange membrane electrodialysis device for deep impurity removal. Under the action of an electric field, ions in the solution will migrate directionally through the ion exchange membrane, with cations moving towards the cathode and anions moving towards the anode, thereby achieving deep removal of trace ions.

[0132] The mass percentage of the dilute hydrochloric acid solution of S1 is 5%.

[0133] The sodium hydroxide solution of S1 has a mass percentage of 3%.

[0134] The S1 strong acid cation exchange resin column is a 001×7 strong acid styrene-based cation exchange resin column.

[0135] The S1 strong basic anion exchange resin column is a D201 macroporous strong basic styrene-based anion exchange resin column.

[0136] The S5 electrodialysis system uses a voltage of 15V and a current density of 20A / m³. 2 .

[0137] The method for preparing the benzocyclobutene high-temperature sintering modified membrane is as follows:

[0138] A1 granulation: Mix 5g titanium dioxide, 1g 4-vinylbenzocyclobutene and 0.05g benzoyl peroxide, ball mill at 200rpm for 4h, and spray dry to granulate;

[0139] A2 molding: The granulated powder is pressed into a film preform by molding.

[0140] A3 Sintering: The preform is sintered at 800℃ for 2 hours to form a cross-linked network between the polymer and the ceramic, resulting in a benzocyclobutene high-temperature sintered modified membrane.

[0141] The A1 granulation process also requires the addition of 3g of polyvinyl alcohol binder and 30g of deionized water.

[0142] The A2 molding pressure is 10 MPa.

[0143] The A3 sintering temperature is 800℃ and the time is 2h.

[0144] Comparative Example 3

[0145] A purification process based on hydroxylamine aqueous solution using a combination of ion exchange membrane and adsorption resin, comprising the following steps:

[0146] S1 Pretreatment: The strongly acidic cation exchange resin column is pretreated with dilute hydrochloric acid solution; the strongly basic anion exchange resin column is pretreated with sodium hydroxide solution; the hydroxylamine aqueous solution is filtered to remove insoluble impurities.

[0147] S2 Cation Exchange: A hydroxylamine aqueous solution containing impurities is passed through a strongly acidic cation exchange resin column at a flow rate of 3 BV / h (BV is the resin bed volume). During this process, the cationic impurities in the solution undergo an exchange reaction with the hydrogen ions on the strongly acidic cation exchange resin, thereby being adsorbed onto the resin and achieving the removal of cationic impurities.

[0148] S3 Anion Exchange: The hydroxylamine solution after cation exchange is passed through a strongly basic anion exchange resin column at a flow rate of 2 BV / h; during this process, anionic impurities in the solution undergo an exchange reaction with hydroxide ions on the strongly basic anion exchange resin and are adsorbed onto the resin, thus removing the anionic impurities.

[0149] S4 purification: The hydroxylamine solution after anion exchange is filtered through a benzocyclobutene high-temperature sintered modified membrane to further improve the purity of the solution.

[0150] S5 Electrodialysis for Deep Impurity Removal: The solution filtered through the modified membrane is introduced into an ion exchange membrane electrodialysis device for deep impurity removal. Under the action of an electric field, ions in the solution will migrate directionally through the ion exchange membrane, with cations moving towards the cathode and anions moving towards the anode, thereby achieving deep removal of trace ions.

[0151] The mass percentage of the dilute hydrochloric acid solution of S1 is 5%.

[0152] The sodium hydroxide solution of S1 has a mass percentage of 3%.

[0153] The S1 strong acid cation exchange resin column is a 001×7 strong acid styrene-based cation exchange resin column.

[0154] The S1 strong basic anion exchange resin column is a D201 macroporous strong basic styrene-based anion exchange resin column.

[0155] The S5 electrodialysis system uses a voltage of 15V and a current density of 20A / m³. 2 .

[0156] The method for preparing the benzocyclobutene high-temperature sintering modified membrane is as follows:

[0157] A1 Granulation: Mix 80g of alumina ceramic powder, 1g of 4-vinylbenzocyclobutene, and 0.05g of benzoyl peroxide, ball mill at 200rpm for 4h, and then spray dry to granulate;

[0158] A2 molding: The granulated powder is pressed into a film preform by molding.

[0159] A3 Sintering: The preform is sintered at 800℃ for 2 hours to form a cross-linked network between the polymer and the ceramic, resulting in a benzocyclobutene high-temperature sintered modified membrane.

[0160] The A1 granulation process also requires the addition of 3g of polyvinyl alcohol binder and 30g of deionized water.

[0161] The A2 molding pressure is 10 MPa.

[0162] The A3 sintering temperature is 800℃ and the time is 2h.

[0163] Table 1 Test results of the examples and comparative examples

[0164] Hydroxylamine content / % Impurity content / ppb Example 1 50.01 20 Example 2 50.03 18 Example 3 50.06 13 Example 4 50.07 11 Comparative Example 1 34.62 188 Comparative Example 2 45.33 72 Comparative Example 3 46.15 58

[0165] Through data analysis of the above embodiments and comparative examples, the present invention can reduce impurity content and achieve efficient separation of hydroxylamine.

[0166] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A purification process based on hydroxylamine aqueous solution using a combination of ion exchange membrane and adsorption resin, the operation steps of which are as follows: S1 Pretreatment: The strongly acidic cation exchange resin column is pretreated with dilute hydrochloric acid solution; the strongly basic anion exchange resin column is pretreated with sodium hydroxide solution; the hydroxylamine aqueous solution is filtered to remove insoluble impurities. S2 Cation Exchange: A hydroxylamine aqueous solution containing impurities is passed through a strongly acidic cation exchange resin column at a flow rate of 3-4 BV / h, where BV is the resin bed volume. During this process, the cationic impurities in the solution undergo an exchange reaction with the hydrogen ions on the strongly acidic cation exchange resin, thereby being adsorbed onto the resin and achieving the removal of cationic impurities. S3 Anion Exchange: The hydroxylamine solution after cation exchange is passed through a strongly basic anion exchange resin column at a flow rate of 2-3 BV / h. In this process, anionic impurities in the solution undergo an exchange reaction with hydroxide ions on the strongly basic anion exchange resin, are adsorbed onto the resin, and the anionic impurities are removed. S4 purification: The hydroxylamine solution after anion exchange is filtered through a benzocyclobutene high-temperature sintered modified membrane to further improve the purity of the solution. S5 Electrodialysis for Deep Impurity Removal: The solution filtered through the modified membrane is introduced into an ion exchange membrane electrodialysis device for deep impurity removal; under the action of an electric field, ions in the solution will migrate directionally through the ion exchange membrane, with cations moving towards the cathode and anions moving towards the anode, thereby achieving deep removal of trace ions; The benzocyclobutene high-temperature sintered modified membrane is prepared by spray drying and granulation of alumina ceramic powder, titanium dioxide, 4-vinylbenzocyclobutene, polyvinyl alcohol, and benzoyl peroxide, followed by molding into a membrane preform and sintering. The preparation method of the benzocyclobutene high-temperature sintering modified film is as follows, according to parts by mass: A1 Granulation: 80-100 parts of alumina ceramic powder and 5-15 parts of titanium dioxide are sintered at 1200-1400℃ for 2-4 hours, cooled, and then 1-3 parts of 4-vinylbenzocyclobutene and 0.05-0.1 parts of benzoyl peroxide are added and mixed. The mixture is ball-milled at 200-400 rpm for 4-8 hours and then spray-dried to granulate. A2 molding: The granulated powder is pressed into a film preform by molding. A3 sintering: The preform is sintered to form a cross-linked network between the polymer and the ceramic, resulting in a benzocyclobutene high-temperature sintered modified membrane; The A1 granulation process also requires the addition of 3-5 parts polyvinyl alcohol binder and 30-50 parts deionized water; The A2 molding pressure is 10-20 MPa; The A3 sintering temperature is 800-1000℃, and the time is 2-4h.

2. The purification process based on hydroxylamine aqueous solution using a combination of ion exchange membrane and adsorption resin according to claim 1, characterized in that: The mass percentage of the dilute hydrochloric acid solution in S1 is 5%.

3. The purification process based on hydroxylamine aqueous solution using a combination of ion exchange membrane and adsorption resin according to claim 1, characterized in that: The sodium hydroxide solution in S1 has a mass percentage of 3%.

4. The purification process based on hydroxylamine aqueous solution using a combination of ion exchange membrane and adsorption resin according to claim 1, characterized in that: The strongly acidic cation exchange resin column of S1 is one of the following: 001×7 strongly acidic styrene-based cation exchange resin column, 001×4 strongly acidic styrene-based cation exchange resin column, and 001×12 strongly acidic styrene-based cation exchange resin column.

5. The purification process based on hydroxylamine aqueous solution using a combination of ion exchange membrane and adsorption resin according to claim 1, characterized in that: The strongly basic anion exchange resin column of S1 is one of the following: D201 macroporous strongly basic styrene-based anion exchange resin column, D202 macroporous II strongly basic styrene-based anion exchange resin column, and D-72A styrene-based macroporous strongly basic anion exchange resin column.

6. The purification process based on hydroxylamine aqueous solution using a combination of ion exchange membrane and adsorption resin according to claim 1, characterized in that: The voltage of the S5 electrodialysis device is 15-20V, and the current density is 20-25A / m. 2 .

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