Environment-friendly production process of triacetone amine

Abstract

The present application relates to a kind of environmentally friendly triacetone amine production process, comprising the following steps: (1) in the presence of ammonium nitrate aqueous solution catalyst, acetone is reacted with ammonia or liquid ammonia to obtain triacetone amine synthesis liquid;(2) triacetone amine synthesis liquid passes through the resin bed filled with weak basic anion exchange resin, and the effluent is the triacetone amine crude product removed ammonium nitrate.The process improves product yield and product quality, reduces the generation of waste water and waste solid, is environmentally friendly, green production.

Description

TECHNICAL FIELD

[0001] The application relates to the chemical industry, in particular to an environment-friendly triacetone amine production process. BACKGROUND

[0002] The aging of polymer materials brings great inconvenience and loss to industrial and agricultural production and people's life. In industry, the service life of materials is often prolonged and the aging of polymer materials is effectively inhibited by adding appropriate light stabilizers to the polymer materials. Hindered amine light stabilizers (HALS) have excellent light stabilizing effect, are a hot topic in the development and research of polymer material stabilization in recent years, and are the most promising type of light stabilizers.

[0003] Triacetone amine, chemically known as 2,2,6,6-tetramethylpiperidone, as the only parent of synthetic HALS, has a fundamental position in the development of hindered amine light stabilizers, and can derive many very practical intermediates and hindered amine light stabilizers, such as 2,2,6,6-tetramethylpiperidinol, 1,2,2,6,6-pentamethylpiperidinol, light stabilizer 770, 944, 3346, etc. In particular, high-stability triacetone amine has obvious quality and cost advantages in the manufacture of 2,2,6,6-tetramethylpiperidinamine, piperidyl diamine, 2,2,6,6-tetramethylpiperidin-4-oxyl radical and new light stabilizer NOR series products. With the increasing demand of the light stabilizer market, the synthesis of triacetone amine has always attracted widespread attention from scientists, and relevant synthesis research reports have been reported. At present, the synthesis routes of triacetone amine reported in the literature mainly include the following two kinds:

[0004] 1. The indirect method is to generate diacetone alcohol, acetone, and pivalone from acetone as raw material under the action of a catalyst, and then to obtain 2,2,6,6-tetramethylpiperidone by continuing to react diacetone alcohol, dipropylamine, acetone, and pivalone under the action of a catalyst. A method for synthesizing 2,2,6,6-tetramethylpiperidone from diacetone alcohol as raw material is disclosed in US4252958; a method for synthesizing 2,2,6,6-tetramethylpiperidone from acetone as raw material is disclosed in US3953459; and a method for obtaining 2,2,6,6-tetramethylpiperidone by reacting pivalone with ammonia is disclosed in US3943139. Although the yield of these methods is acceptable, the synthesis and separation of acetone, pivalone, and diacetone alcohol are quite difficult, and the use of these methods greatly increases the production cost, thus it is difficult to realize industrialized production.

[0005] 2、Direct method is to use acetone and ammonia as raw materials, in the presence of catalyst to directly synthesis triacetoneamine method. Compared with the indirect method, can avoid the separation and purification of intermediate product, can greatly save manpower and material resources, reduce production cost, the method although the yield is acceptable, but the catalyst ammonium nitrate in to the reaction end point after the continuous catalytic effect, produce a large number of by-products, and ammonium nitrate itself has the risk of explosion, must be destroyed after ammonium nitrate reaches the end point of the reaction. Domestic industrial production of triacetoneamine, all use sodium hydroxide to destroy the ammonium nitrate in the synthesis liquid to stop the catalytic effect, thus producing the consumption of alkali and the extremely difficult to handle of high salt alkali (sodium nitrate and sodium hydroxide) wastewater. The produced sodium nitrate always exists the risk of explosion in the post-processing process, and the residual liquid alkali in the triacetoneamine reaction liquid post-processing process makes the triacetoneamine continue to occur side reaction in the rectification process of the reaction system, thereby increasing the triacetoneamine discharge residue, increasing the production cost. SUMMARY

[0006] The purpose of the patent is to provide an environmentally friendly triacetoneamine production process, which can reduce the production of heavy component impurities, reduce energy consumption, improve yield, and realize the recycling of ammonium nitrate catalyst aqueous solution under the premise of not producing a large amount of high salt alkali wastewater.

[0007] An environmentally friendly triacetoneamine production process, comprising the following steps:

[0008] (1) In the presence of ammonium nitrate aqueous solution catalyst, acetone reacts with ammonia gas or liquid ammonia to obtain triacetoneamine synthesis liquid;

[0009] (2) The triacetoneamine synthesis liquid passes through the weakly basic anion exchange resin, and the effluent is the triacetoneamine crude product after removing ammonium nitrate.

[0010] In the present application, the ammonium nitrate catalyst is added in the form of aqueous solution, which can reduce the risk of explosion, and after the reaction is completed, the weakly basic anion exchange resin reacts with the ammonium nitrate catalyst to convert the ammonium nitrate into ammonia water, thereby avoiding the generation of high salt wastewater caused by the treatment of ammonium nitrate with sodium hydroxide. The converted ammonia water can be recovered by deamination in the distillation process of the product. The resin bed after use can be converted into ammonium nitrate by regeneration method, and continue to be used in the next batch of triacetoneamine synthesis process, so as to achieve the effect of reducing cost and increasing efficiency, green and environmental protection.

[0011] In the specific embodiment, in step (2), the weakly basic anion exchange resin is selected from chloro type weakly basic anion exchange resin or free radical type weakly basic anion exchange resin. Preferably, it is a free radical type weakly basic anion exchange resin.

[0012] In specific embodiments, in step (2), the weak base anion exchange resin is an amine functional group containing anion resin, including tertiary amine functional group, quaternary amine functional group, secondary amine functional group or polyamine group anion exchange resin.

[0013] The resin material includes one or more of acrylic resin, styrene resin, styrene-divinyl benzene resin.

[0014] The weak base anion exchange resin in the present application is selected from one or more of Dow MARATHON TM WBA, Mitsubishi WA10, WA20, WA30, WA30LL, DuPont AmberLite TM HPR6700, AmberLite TM HPR7000, AmberLite TM HPR9500, AmberLite TM HPR9600, AmberLite TM HPR9700, Rohm & Haas MP62, MonoPius MP 64, MonoPius MP 68, Rohm & Haas AmberLite IRA67, AmberLite IRA67RF, AmberLite IRA96, AmberLite IRA96RF, different resins affect the rate of recovery of ammonium nitrate and the resin regeneration rate and ammonia consumption, preferably, the weak base anion exchange resin is one or more of Mitsubishi WA30LL, Rohm & Haas MP62, Rohm & Haas AmberLite IRA96RF.

[0015] In specific embodiments, in step (2), the weak base anion exchange resin is filled into a resin bed, preferably, the filling volume of the weak base anion exchange resin is 10%-50% of the volume of the triacetone amine synthesis liquid, for example 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%. Preferably 25-35%.

[0016] In specific embodiments, in step (2), the temperature of the triacetone amine synthesis liquid passing through the weak base anion exchange resin bed is 20-80℃, for example 20℃, 30℃, 40℃, 50℃, 60℃, 70℃, 80℃. Preferably 30-40℃.

[0017] The time of the triacetone amine passing through the weak base anion exchange resin bed is appropriate for the conversion of the ammonium nitrate catalyst, in specific embodiments of the present application, the passing time is 1-5h, preferably 2-3h.

[0018] In the present application, the used weakly basic anion exchange resin can be reused after regeneration, in order to make each material reusable, the regeneration method comprises: respectively passing ammonia water and pure water through the resin bed in sequence at a flow rate of 1-2 m 3 / h, specifically, the ammonia water can be passed through the resin bed at a flow rate of 1-2 m 3 / h, and the effluent is an ammonium nitrate-ammonia water solution, and then the pure water is passed through the resin bed at the same flow rate and flow direction until the pH of the effluent is 8-10.

[0019] In the regeneration method, the concentration of the used ammonia water is 25%-50%, which can be freshly prepared ammonia water or recycled reused ammonia water.

[0020] In order to achieve better regeneration effect and save energy, in the specific embodiment, in the weakly basic anion exchange resin regeneration method, the amount of ammonia water is 2-5 times the volume of the resin, preferably 3-4 times. The amount of pure water used is 1-2 times the volume of the resin bed.

[0021] The ammonium nitrate-ammonia water solution is concentrated by deamination and recovered for synthesis, and both ammonia water and ammonium nitrate can be recycled.

[0022] In the specific embodiment, in step (1), acetone and aqueous nitrate solution are added to the reaction container, then liquid ammonia is introduced, and the reaction is carried out under heat. After the reaction is completed, a triacetone amine synthesis solution is obtained.

[0023] In the specific embodiment, in step (1), the concentration of the aqueous ammonium nitrate solution is 50-70%; for example, 50%, 55%, 60%, 65%, or 70%; within this concentration range, the reaction can be promoted to proceed stably and the risk of explosion can be reduced, which is suitable for industrial production.

[0024] In the specific embodiment, in step (1), the mass ratio of acetone to liquid ammonia is 15:1-45:1, preferably 25:1-35:1.

[0025] In the specific embodiment, in step (1), the mass ratio of acetone to liquid ammonia is 30:1-70:1, preferably 40:1-50:1.

[0026] In the specific embodiment, in step (1), the reaction temperature is 40-100℃, preferably 60-80℃.

[0027] In the specific embodiment, in step (1), the ammonia introduction temperature is 30-70℃, preferably 50-60℃.

[0028] In the specific embodiment, in step (1), the reaction time in step (1) is 2-12h, preferably 7-9h.

[0029] In the specific embodiment, the production process further comprises:

[0030] Step (3): The crude triacetone amine is subjected to rectification in a rectification tower to obtain triacetone amine product.

[0031] The rectification can be performed by any method known in the art, preferably, the light components in the front fraction of the rectification are recovered and recycled, the overhead sample is collected when the sample is qualified.

[0032] The present application has the following positive effects:

[0033] (1) The weakly basic anion exchange resin can adsorb and neutralize ammonium nitrate, avoiding the generation of sodium nitrate, and reducing the generation of heavy component impurities in the rectification step, thereby increasing the product yield by 2-5% and increasing the purity to more than 99%.

[0034] (2) The use of weakly basic anion exchange resin does not require treatment of high-salinity wastewater generated by neutralizing the catalyst, reducing pollution and energy consumption.

[0035] (3) The resin can be regenerated, and ammonium nitrate can be recycled and used, thereby reducing the generation of wastewater and waste solids, saving resources, and reducing costs and increasing efficiency. DETAILED DESCRIPTION

[0036] The present application will be described in detail below in conjunction with specific embodiments, but it should be noted that the scope of protection of the present application is not limited by these specific embodiments and principle explanations, but is determined by the claims.

[0037] In the present application, any matter or item not mentioned in addition to the explicitly described content is directly applicable to those known in the art without any change. Moreover, any embodiment described herein can be freely combined with one or more other embodiments described herein, and the technical solutions or technical ideas formed thereby are considered as part of the original disclosure or original description of the present application, and should not be considered as new content not disclosed or anticipated herein, unless the combination is considered to be obviously unreasonable by those skilled in the art.

[0038] All features disclosed in the present application can be combined arbitrarily, and these combinations should be understood as disclosed or described in the present application, unless the combination is considered to be obviously unreasonable by those skilled in the art.

[0039] The numerical points disclosed in the present specification include not only the numerical points specifically disclosed in the examples, but also the endpoints of the numerical ranges in the specification, and the ranges formed by the arbitrary combination of these numerical points should be considered as the ranges disclosed or described in the present application.

[0040] In the present application, the technical and scientific terms are defined as per their definitions, and those not given a definition are understood according to the usual meaning in the art.

[0041] Currently, the industrial production of triacetone amine with ammonium nitrate as catalyst needs to add a strong base such as sodium hydroxide to neutralize ammonium nitrate used as a catalyst, which produces a large amount of wastewater, brings difficulties to the post-treatment, and also has a security risk if not properly treated. The present application relates to an environmentally friendly triacetone amine post-treatment process, that is, using weakly basic anion exchange resin to convert ammonium nitrate into ammonia water through ion exchange, and then recycling in the triacetone amine rectification process by deamination. The used ion exchange resin is regenerated by washing with ammonia water, and the produced ammonium nitrate aqueous solution is continuously used as a catalyst for the next batch of triacetone amine synthesis, achieving the purpose of cost reduction and efficiency improvement, green environmental protection.

[0042] The present application provides an environmentally friendly triacetone amine production process, comprising the following steps:

[0043] (1) sequentially adding acetone and ammonium nitrate aqueous solution into the reaction kettle, opening the stirring, and heating to 30-70℃ to pass ammonia gas or liquid ammonia into the kettle, and after the ammonia passing is finished, the temperature is controlled at 40-100℃, and maintained for 2-12h, after the reaction is finished, the temperature of the reaction liquid is reduced to room temperature, the stirring is turned off, and the triacetone amine synthesis liquid is obtained;

[0044] (2) passing the triacetone amine synthesis liquid through a resin bed filled with weakly basic anion exchange resin, the filling volume is 10%-50% of the volume of the synthesis liquid, the temperature is 20-80℃, the passing time is 1-5h, and the effluent is triacetone amine crude product without ammonium nitrate;

[0045] (3) the triacetone amine crude product enters the rectification tower for rectification, the front fraction is recycled, after the overhead sample is qualified, the product is collected, and the high content triacetone amine product is obtained;

[0046] (4) resin regeneration, passing 25-50% concentration ammonia water with an amount of 2-5 times the volume of the resin through the resin bed, the passing time is 2-3h, the effluent is ammonium nitrate-ammonia water solution, and after deamination and concentration, it is recycled to synthesis, and the same flow rate and flow direction are used to prepare 2 times the volume of the resin desalting water, and the desalting water is passed until the effluent pH is about 8, and the resin bed is ready for use.

[0047] The process of the present application not only reduces the generation of wastewater and waste solids, but also improves the quality and yield of the product, and has strong operability, and is suitable for industrial production.

[0048] The following examples are used to illustrate the technical solutions of the present application:

[0049] Example 1

[0050] (1) Into a reactor, add acetone 100 g (1.72 mol) and 60% ammonium nitrate aqueous solution 3.33 g in sequence, open the stirring, and warm up to 50°C. Then, pass liquid ammonia 4 g (0.235 mol) into the reactor. After the ammonia passing is completed, control the temperature at 70°C for 8 h. After the reaction is completed, open the cooling water to reduce the temperature of the reaction liquid to room temperature, and then close the stirring to obtain a triacetone amine synthesis liquid;

[0051] (2) Pass the triacetone amine synthesis liquid through a resin bed filled with Rohm & Haas Amberlite IRA96RF weakly basic anion exchange resin, with a filling volume of 30% of the synthesis liquid volume, at a temperature of 35°C for 3 h. The effluent is a crude triacetone amine product with ammonium nitrate removed, with a pH value of 10-11;

[0052] (3) The crude triacetone amine product is subjected to rectification in a rectification tower. The forefraction is recycled. After the sampling at the top of the tower is qualified, the product is collected to obtain a triacetone amine product 33.66 g (0.217 mol) with a yield of 92.34% and a purity of 99.5%;

[0053] (4) Regenerate the resin by passing ammonia water with a concentration of 25% and a dosage of 3 times the volume of the resin through the resin bed at a passing time of 2 h. The effluent is an ammonium nitrate-ammonia water solution. After the ammonia is removed and concentrated, it is recycled to the synthesis. Prepare water with a volume of 2 times the volume of the resin, and pass the water through the resin bed until the pH value of the effluent is about 8. The resin bed is ready for use.

[0054] Example 2

[0055] (1) Into a reactor, add acetone 100 g and 60% ammonium nitrate aqueous solution 3.33 g in sequence, open the stirring, and warm up to 50°C. Then, pass liquid ammonia 4 g into the reactor. After the ammonia passing is completed, control the temperature at 70°C for 8 h. After the reaction is completed, open the cooling water to reduce the temperature of the reaction liquid to room temperature, and then close the stirring to obtain a triacetone amine synthesis liquid;

[0056] (2) Pass the triacetone amine synthesis liquid through a resin bed filled with Rohm & Haas Amberlite IRA96RF weakly basic anion exchange resin (used after regeneration in Example 1), with a filling volume of 30% of the synthesis liquid volume, at a temperature of 35°C for 3 h. The effluent is a crude triacetone amine product with ammonium nitrate removed, with a pH value of 10-11;

[0057] (3) The crude triacetone amine product is subjected to rectification in a rectification tower. The forefraction is recycled. After the sampling at the top of the tower is qualified, the product is collected to obtain a triacetone amine product 33.66 g (0.217 mol) with a yield of 92.34% and a purity of 99.5%;

[0058] (4) Resin regeneration, ammonia water with concentration of 25% and amount of 3 times of resin volume was passed through the resin bed for 2 h, the effluent was ammonium nitrate-ammonia water solution, which was concentrated to remove ammonia and then recycled to the synthesis. Then, water with volume of 2 times of resin volume was prepared and passed through the resin bed until the pH of the effluent was about 8, and the resin bed was ready for use.

[0059] Example 3

[0060] (1) 100 g of acetone and 3.33 g of 60% ammonium nitrate solution were sequentially added to a reaction kettle, stirring was turned on, and liquid ammonia 4 g was passed into the kettle at 50°C. After the ammonia passing was completed, the temperature was controlled at 70°C for 8 h. After the reaction was completed, cooling water was turned on to reduce the temperature of the reaction liquid to room temperature, and stirring was turned off to obtain a triacetone amine synthesis liquid;

[0061] (2) The triacetone amine synthesis liquid was passed through a resin bed filled with weakly basic anion exchange resin (used after regeneration in Example 2), with a filling volume of 30% of the synthesis liquid volume, a passing temperature of 35°C, and a passing time of 3 h. The effluent was a crude triacetone amine product with ammonium nitrate removed, with a pH value of 10-11;

[0062] (3) The crude triacetone amine product was subjected to rectification in a rectification column, the front fraction was recycled, and after the sample on the top of the column was qualified, the product was collected to obtain 33.64 g of triacetone amine product, with a yield of 92.33% and a purity of 99.2%;

[0063] (4) Resin regeneration, ammonia water with concentration of 25% and amount of 3 times of resin volume was passed through the resin bed for 2 h, the effluent was ammonium nitrate-ammonia water solution, which was concentrated to remove ammonia and then recycled to the synthesis. Then, water with volume of 2 times of resin volume was prepared and passed through the resin bed until the pH of the effluent was about 8, and the resin bed was ready for use.

[0064] Example 4

[0065] (1) 100 g of acetone and 3.33 g of 60% ammonium nitrate solution were sequentially added to a reaction kettle, stirring was turned on, and liquid ammonia 4 g was passed into the kettle at 50°C. After the ammonia passing was completed, the temperature was controlled at 70°C for 8 h. After the reaction was completed, cooling water was turned on to reduce the temperature of the reaction liquid to room temperature, and stirring was turned off to obtain a triacetone amine synthesis liquid;

[0066] (2) The triacetone amine synthesis liquid was passed through a resin bed filled with weakly basic anion exchange resin (used after regeneration in Example 2), with a filling volume of 30% of the synthesis liquid volume, a passing temperature of 35°C, and a passing time of 3 h. The effluent was a crude triacetone amine product with ammonium nitrate removed, with a pH value of 10-11;

[0067] (3) The crude triacetone amine is fed into a rectifying tower for rectification, the front fraction is recycled, after the sampling of the tower top is qualified, the product is collected, and triacetone amine product 33.23 g is obtained, the yield is 91.34%, and the purity is 99.1%;

[0068] (4) Resin regeneration, 25% concentration, 4 times the volume of the resin of ammonia water is passed through the resin bed, the passing time is 4 h, the effluent is an ammonium nitrate-ammonia water solution, after ammonia removal and concentration, it is recycled to synthesis, and then water with a volume of 3 times the volume of the resin is prepared and passed through the resin bed in the same flow rate and flow direction until the pH of the effluent is about 8, and the resin bed is ready for use.

[0069] Example 5

[0070] (1) 100 g of acetone and 3.33 g of 60% ammonium nitrate aqueous solution are sequentially added to a reaction kettle, stirring is turned on, and 4 g of liquid ammonia is passed into the kettle at 50°C, after the ammonia passing is completed, the temperature is controlled at 70°C, and the temperature is kept for 8 h, after the reaction is completed, cooling water is turned on to reduce the temperature of the reaction solution to room temperature, stirring is turned off, and triacetone amine synthesis solution is obtained;

[0071] (2) The triacetone amine synthesis solution is passed through a resin bed filled with Rohm & Haas Amberlite IRA96RF weak basic anion exchange resin, the filling volume is 10% of the volume of the synthesis solution, the passing temperature is 70°C, the passing time is 10 h, and the effluent is crude triacetone amine with the removal of ammonium nitrate, and the pH value is 10-11;

[0072] (3) The crude triacetone amine is fed into a rectifying tower for rectification, the front fraction is recycled, after the sampling of the tower top is qualified, the product is collected, and triacetone amine product 33.34 g is obtained, the yield is 91.64%, and the purity is 99.2%;

[0073] (4) Resin regeneration, 25% concentration, 4 times the volume of the resin of ammonia water is passed through the resin bed, the passing time is 4 h, the effluent is an ammonium nitrate-ammonia water solution, after ammonia removal and concentration, it is recycled to synthesis, and then water with a volume of 3 times the volume of the resin is prepared and passed through the resin bed in the same flow rate and flow direction until the pH of the effluent is about 8, and the resin bed is ready for use.

[0074] Comparative Example 1

[0075] (1) 100 g of acetone and 3.33 g of 60% ammonium nitrate aqueous solution are sequentially added to a reaction kettle, stirring is turned on, and 4 g of liquid ammonia is passed into the kettle at 50°C, after the ammonia passing is completed, the temperature is controlled at 70°C, and the temperature is kept for 8 h, after the reaction is completed, cooling water is turned on to reduce the temperature of the reaction solution to room temperature, stirring is turned off, and triacetone amine synthesis solution is obtained;

[0076] (2) 3.5 g of flake caustic is added to the triacetone amine synthesis solution, stirring is performed for 1 h, and after standing for 2 h, 6.71 g of high-salt wastewater is separated, crude triacetone amine is obtained, and the pH value is 9-10.

[0077] (3) The crude triacetone amine enters the rectifying column for rectification, the front fraction is recycled, after the top sampling is qualified, the product is collected, and triacetone amine product 32.35 g is obtained, the yield is 88.93%, and the purity is 98.3%.

[0078] Although the present application has been described in detail with general description, specific embodiments and experiments above, some modifications or improvements can be made on the basis of the present application, which is obvious to those skilled in the art. Therefore, these modifications or improvements made on the basis of not deviating from the spirit of the present application, all belong to the scope of the present application claimed.

Claims

1. A production process of triacetone amine, comprising the following steps: (1) reacting acetone with ammonia gas or liquid ammonia in the presence of an aqueous ammonium nitrate catalyst to obtain a triacetone amine synthesis solution; (2) passing the triacetone amine synthesis solution through a weakly basic anion exchange resin, and the effluent being a triacetone amine crude product from which ammonium nitrate has been removed. In step (1), the concentration of the aqueous ammonium nitrate is 50-70%. In step (1), the reaction time is 2-9 h. In step (2), the weakly basic anion exchange resin is a free radical type weakly basic anion exchange resin, and the weakly basic anion exchange resin is a weakly basic anion exchange resin having a secondary amine or tertiary amine functional group.

2. The production process according to claim 1, characterized in that, The weakly basic anion exchange resin is one or more of Mitsubishi WA30LL, Rohm & Haas MP62, and Rohm & Haas Amberlite IRA96RF.

3. The production process according to claim 1, characterized in that, The weakly basic anion exchange resin is packed into a resin bed.

4. The production process according to claim 3, characterized in that, The packing volume of the weakly basic anion exchange resin is 10-50% of the volume of the triacetone amine synthesis solution.

5. The production process according to claim 3, characterized in that, The packing volume of the weakly basic anion exchange resin is 25-35% of the volume of the triacetone amine synthesis solution.

6. The production process according to any one of claims 1 to 5, characterized in that, The temperature at which the triacetone amine synthesis solution passes through the weakly basic anion exchange resin bed is 20-80℃.

7. The production process according to any one of claims 1 to 5, characterized in that, The used weakly basic anion exchange resin can be reused after regeneration.

8. The production process according to claim 7, characterized in that, The regeneration method includes: sequentially passing ammonia water and pure water through the resin bed at a flow rate of 1-2 m 3 / h, respectively.

9. The production process according to claim 8, characterized in that, The concentration of the ammonia water used is 25-50%.

10. The production process according to claim 8, characterized in that, The amount of the ammonia water used is 2-5 times the volume of the resin bed, and the amount of the purified water used is 1-2 times the volume of the resin bed.

11. The production process according to claim 1, characterized in that, The production process further comprises: Step (3): distilling the triacetone amine crude product through a rectifying column to obtain a triacetone amine product.

12. The production process according to claim 11, characterized in that, The light components in the distillation are recovered and reused, and a sample is taken from the top of the column, and the product is collected after the sample is qualified.