Method and system for recovering CL-20 in strong acid waste liquid by using macroporous adsorption resin

Abstract

The invention discloses a method and system for recycling CL-20 in strong acid waste liquid through macroporous adsorption resin, and belongs to the technical field of environmental remediation. The method comprises the steps that the macroporous adsorption resin is added into the strong acid waste liquid containing CL-20, and an adsorption reaction is conducted under set conditions; after the adsorption is completed, separating the resin saturated by adsorption from the waste liquid, and treating the resin saturated by adsorption by utilizing a desorption agent; putting the desorbed resin into the waste liquid containing CL-20 again for adsorption, and repeating adsorption-desorption; and treating the solution containing CL-20 obtained by adsorption-desorption to obtain a CL-20 solid. According to the method disclosed by the invention, the CL-20 adsorption rate can reach 97% or above under the condition that the adding amount of the resin is 10g / L, the concentration of the CL-20 in ethyl acetate after three times of circulation can reach 2.60 g / L, the content of the CL-20 in the finally recovered solid is 37.87%, and the total recovery rate reaches 58.25%. The invention provides an efficient, economic and environment-friendly CL-20 recovery method, the treatment problem of the CL-20-containing strong acid waste liquid can be effectively solved, and meanwhile, the recycling of valuable chemicals is realized.

Description

Technical Field

[0001] The present invention relates to the technical field of environmental remediation, and in particular to a method and system for recovering CL-20 using a macroporous adsorption resin. Background Art

[0002] Hexanitrohexaazaisowurtzitane (chemical formula C6H6N 12 O 12 , referred to as HNIW, commonly known as CL-20), is the most powerful non-nuclear detonating explosive known to date. Its power is 14%-20% higher than that of cyclotetramethylene tetranitramine (referred to as HMX, also known as Octogen). Its excellent comprehensive performance allows it to be used as explosives and propellants for rockets, spacecraft, missiles, etc. It plays a very important role in the fields of industry and military, and has high commercial value. But at the same time, CL-20 is very expensive, and its high production cost restricts its use. The production, assembly, and use of explosives will lead to environmental exposure of explosives, and the explosive pollution caused by military processes is even more serious.

[0003] In addition to dilution and dispersion, the fate of CL-20 exposed to the environment is mainly adsorption in soil and minerals, as well as abiotic and biotic transformation. Adsorption can reduce the mobility of pollutants in the environment, thereby reducing their biological toxicity. A basic understanding of the adsorption and desorption mechanisms is essential for accurately predicting the fate and impact of organic pollutants in soil and groundwater. Some soil properties, including organic carbon content, pH value, cation exchange capacity (CEC), and the amount and type of clay, may affect the adsorption of organic compounds in the environment. The adsorption rate of CL-20 in soil sediments is very fast, and adsorption equilibrium can be reached within 4 minutes after contact. The half-adsorption period is only 0.8 minutes, but the half-desorption period is only 22 minutes. The adsorption is not very stable. The adsorption of CL-20 by sediments has basically no obvious delay effect on the migration of CL-20 in the soil, and the adsorption of CL-20 by sediments is very small, and the standard distribution coefficient K d Values ​​range from 0.22 to 3.8 cm 3 ·g -1 Therefore, the risk of CL-20 pollution in soil causing serious groundwater pollution is very high; some non-biological processes in the natural environment can achieve oxidative degradation of CL-20, but the degradation effect is very weak and incomplete, which will produce nitrite (NO2 - ), nitrate (NO3 - ), ammonium (NH4 +), formic acid (HCOOH) and glyoxal (CHOCHO). Studies have shown that the half-life of CL-20 in nature is between 144 days and 686 days, indicating that CL-20 can exist stably for a long time in the natural environment; on the other hand, the products of incomplete degradation of CL-20 will also have a huge impact on the environment. Exposure to CL-20 in the environment will have a series of effects on the surrounding organisms and ecological environment. CL-20 from food intake and environmental exposure has little effect on Japanese quail adults, but has a great impact on embryos, leading to abnormalities such as skull and facial deformities, beak curvature, enlarged midbrain, and classic unilateral development with micro eyes during embryonic development in birds, and also reducing the number of eggs laid by female birds. Earthworms show physiological effects such as developmental delay, stiffness, and body atrophy under CL-20 exposure. Exposure to CL-20 affects the abundance and concentration of microarthropods in the soil. CL-20 also has certain physiological toxicity to mammals. CL-20 destroys the balance of endogenous oxidation and antioxidant defense mechanisms of hamsters, thereby causing oxidative damage to DNA and mitochondrial DNA (mtDNA), inducing genetic toxicity in V79 cells.

[0004] Typical removal methods for CL-20 include adsorption, alkaline hydrolysis, advanced oxidation, and biological methods. The alkaline hydrolysis and advanced oxidation methods do not completely degrade CL-20, and substances such as formic acid, nitrite, and nitrate in the product, and pollutants are not completely removed. The biological method can achieve complete degradation of CL-20, but the degradation rate is slow, and most common microorganisms have no ability to degrade CL-20, requiring strain screening. The adsorption method is low-cost, simple to operate, and can also achieve material recycling with the desorption process. However, there is currently no research focusing on the adsorption treatment of waste acid generated by the CL-20 production process, nor is there any research focusing on the huge recovery potential and value of CL-20 in waste acid. Therefore, process methods for the treatment and resource utilization of waste acid from CL-20 production are urgently needed to be developed. Summary of the invention

[0005] In order to solve the deficiencies in the prior art, the present invention provides a method for recovering hexanitrohexaazaisowurtzitane (CL-20) from waste liquid containing high-concentration strong acid using a macroporous adsorption resin. The method selects a macroporous adsorption resin for commercial water treatment, and develops a method of adsorption-analysis-evaporation crystallization based on it, so as to realize the recovery of CL-20 in waste acid. The method has the advantages of high recovery rate, low cost, simple operation, and environmental friendliness, and can effectively recover CL-20 from production waste liquid, realize the recycling of resources, and reduce environmental pollution.

[0006] The present invention adopts the following technical solution.

[0007] The first aspect of the present invention discloses a method for recovering CL-20 from strong acid waste liquid using a macroporous adsorption resin, comprising the following steps:

[0008] Resin screening: Select macroporous adsorption resins with set physical and chemical properties;

[0009] Adsorption: Add macroporous adsorption resin into the strong acid waste liquid containing CL-20, and perform adsorption reaction under set conditions;

[0010] Desorption: After the adsorption is completed, the saturated resin is separated from the waste liquid, and then the desorbent is used to treat the saturated resin under set conditions;

[0011] Cyclic adsorption-desorption: the desorbed resin is put back into the waste liquid containing CL-20 for adsorption, and the adsorption-desorption process is repeated for multiple cycles;

[0012] Recovery: The solution containing CL-20 obtained by adsorption-desorption is distilled, centrifuged and dried to obtain CL-20 solid.

[0013] Preferably, the resin with set physical and chemical properties means that the resin needs to withstand a strong acidic environment with a pH value less than 1.

[0014] Preferably, the setting conditions for the adsorption are: placing the resin and the strong acid waste liquid mixture containing CL-20 in a constant temperature water bath shaker at room temperature, and oscillating and adsorbing at a speed of 0-200 rpm for 0-6 hours.

[0015] Preferably, the desorption process specifically includes:

[0016] A vacuum filtration device is used to separate the adsorption saturated resin from the waste liquid;

[0017] The adsorption saturated resin is immersed in the desorption agent and the desorption operation is carried out under the set conditions.

[0018] Preferably, the analytical adjuvant is any one of methanol, ethanol, acetone or ethyl acetate.

[0019] Preferably, the setting conditions are: placing the adsorption saturated resin and the adsorbent in a reaction container, and oscillating and adsorbing at a rotation speed of 0-200 rpm for 0-30 minutes in a constant temperature water bath shaker.

[0020] Preferably, in the cyclic adsorption-desorption process, new CL-20 strong acid waste liquid is used in each cycle, and the resin is washed with deionized water without replacing the desorbent.

[0021] Preferably, the recycling process comprises:

[0022] The desorbent solution containing CL-20 is mixed with an equal volume of deionized water, and treated under set conditions to remove the desorbent to obtain a solution containing CL-20;

[0023] The solution containing CL-20 was centrifuged, and the precipitate was washed with deionized water, and finally freeze-dried to obtain CL-20 solid.

[0024] Preferably, the set conditions are to adopt a hydrothermal co-bath reduced pressure distillation method and distill at 80°C to 90°C for 30 to 40 minutes.

[0025] The second aspect of the present invention discloses a system for recovering CL-20 from strong acid waste liquid by using a macroporous adsorption resin, and the method for recovering CL-20 from strong acid waste liquid by using a macroporous adsorption resin comprises: an adsorption module, a desorption module and a recovery module;

[0026] The adsorption module includes a constant temperature water bath shaker for adsorbing CL-20 in the strong acid waste liquid;

[0027] The desorption module includes a vacuum filtration device and a constant temperature water bath shaker, which are used to desorb the saturated resin;

[0028] The recovery module includes a vacuum distillation device and a freeze dryer, and is used for recovering CL-20.

[0029] Compared with the prior art, the beneficial effects of the present invention include at least:

[0030] The present invention discloses an efficient, economical and environmentally friendly technical solution for recovering CL-20 by using macroporous adsorption resin, which includes four steps of adsorption, desorption, cyclic adsorption-desorption and recovery, and can effectively solve the problem of treating strong acid waste liquid containing CL-20, while realizing the recovery and utilization of valuable chemicals, and highlighting the advantages of the present invention compared with the prior art:

[0031] 1. High recovery rate: The recovery rate of CL-20 can reach more than 58.25%, and the recovery rate is even higher in actual industrial applications.

[0032] 2. Low cost: Use cheap and readily available adsorbents and desorbents to reduce production costs.

[0033] 3. Easy to operate: The operation steps are simple and easy to control, without complicated equipment and operation.

[0034] 4. Environmentally friendly: Reduce the pollution of CL-20 to the environment, in line with the concept of sustainable development.

[0035] 5. CL-20 enrichment can be achieved: Through cyclic adsorption-desorption operation, CL-20 can be effectively enriched and the recovery efficiency can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 This is the process flow for recycling CL-20 in Example 1;

[0037] Figure 2 The effects of different resins and parameters on adsorption in Example 2, where (a), (c), (e), and (g) are different dosages of DA201-C, NKA-2, D730, and D121 resins, respectively; (b), (d), (f), and (h) are the adsorption times of DA201-C, NKA-2, D730, and D121 resins, respectively;

[0038] Figure 3 The effects of different parameters on the desorption in Example 3, where (a) is the type of desorption agent; (b) is the desorption time; (c) is the number of cycles;

[0039] Figure 4 The liquid chromatogram of the solution of Example 4, wherein (a) is the production waste acid; and (b) is the ethyl acetate analysis solution. DETAILED DESCRIPTION

[0040] In order to make the purpose, technical scheme and advantages of the present invention clearer, the technical scheme of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. The embodiments described in this application are only embodiments of a part of the present invention, rather than all embodiments. Based on the spirit of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work belong to the protection scope of the present invention.

[0041] The inventors have found that polymer resins, especially macroporous adsorption resins, have a large surface area comparable to that of activated carbon, stable physical and chemical properties, and are resistant to strong acid and alkali environments, and are widely used in the field of wastewater treatment. In addition, polymer resins have excellent regeneration performance, the adsorbate is easy to desorb, and the adsorption performance is stable. Common resins used for water treatment include polystyrene resins, acrylic resins, phenolic resins, etc.

[0042] The concentrated nitric acid and sulfuric acid mixture produced during the CL-20 production process contains a large amount of CL-20, and the waste acid is difficult to treat. However, at the same time, the high concentration of CL-20 has a very high recovery value.

[0043] Therefore, this study selected macroporous adsorption resins for commercial water treatment, screened out the resins with the best adsorption effect, and based on this, developed a method of adsorption-desorption-evaporation crystallization to achieve efficient recovery of CL-20 from production waste acid.

[0044] An embodiment of the present invention provides a method for recovering hexanitrohexaazaisowurtzitane (CL-20) using a macroporous adsorption resin, comprising the following steps:

[0045] Step 1. Resin screening:

[0046] After preliminary screening of physical and chemical properties, macroporous adsorption resin was selected for adsorption of CL-20;

[0047] In a preferred but non-limiting embodiment of the present invention, the screening of the physical and chemical properties is that the resin selected for the method must be able to withstand a strongly acidic environment with a pH value less than 1 and have a good adsorption capacity for organic matter;

[0048] More preferably, the macroporous adsorption resin may be: DA201-C (polystyrene), NKA-2 (polystyrene), D730 (acrylic acid), D121 (phenolic formaldehyde).

[0049] Step 2. Adsorption:

[0050] The macroporous adsorption resin is added into the strong acid waste liquid containing CL-20, and the adsorption reaction is carried out under the set conditions;

[0051] In a preferred but non-limiting embodiment of the present invention, NKA-2 type hyper-crosslinked polystyrene resin is preferably used as the adsorbent, which has the best adsorption performance for CL-20, and the adsorption rate can reach more than 97%.

[0052] NKA-2 resin has a regular spherical structure, rich porous structure and large specific surface area. It is rich in functional groups such as phenolic hydroxyl groups and benzene rings, and can interact strongly with CL-20 molecules, thereby achieving efficient adsorption.

[0053] Further preferably, the set condition is to place the resin and the strong acid waste liquid mixture containing CL-20 in a constant temperature water bath shaker at room temperature, and oscillate and adsorb at a speed of 0-200 rpm for 0-6 hours.

[0054] Step 3. Desorption:

[0055] After the adsorption is completed, the saturated resin is separated from the waste liquid, and then the desorbent is used to treat the saturated resin under set conditions.

[0056] Specifically, the method includes: using a vacuum filtration device to separate the adsorption saturated resin from the waste liquid, using methanol, ethanol, acetone or ethyl acetate as a desorbent, immersing the adsorption saturated resin in a desorption agent, and performing a desorption operation under set conditions.

[0057] In a preferred but non-limiting embodiment of the present invention, the desorption efficiency of CL-20 by ethyl acetate is the highest, which can reach more than 95%, and CL-20 has a high solubility in ethyl acetate, which is convenient for subsequent recovery and purification.

[0058] Further preferably, the set condition is to place the adsorption saturated resin and the adsorbent in a reaction container, and oscillate and adsorb at a rotation speed of 0-200 rpm for 0-30 minutes in a constant temperature water bath shaker.

[0059] Step 4. Cyclic adsorption-desorption:

[0060] The desorbed resin is put back into the waste liquid containing CL-20 for adsorption, and steps 2 and 3 are repeated for multiple cycles.

[0061] New CL-20 strong acid waste liquid was used in each cycle, and the resin was cleaned with deionized water without replacing the desorbent.

[0062] In a preferred but non-limiting embodiment of the present invention, the cycle is preferably performed three times to further increase the concentration of CL-20 in ethyl acetate to achieve the purpose of enriching CL-20.

[0063] The cyclic operation can effectively improve the recovery efficiency of CL-20 and reduce the amount of desorbent.

[0064] Step 5. Recycling:

[0065] The ethyl acetate solution rich in CL-20 obtained in step 4 is distilled, centrifuged and dried to obtain a CL-20 solid.

[0066] Specifically, the ethyl acetate solution rich in CL-20 is mixed with an equal volume of deionized water, and the ethyl acetate is removed by distillation at 80° C. to 90° C. for 30 to 40 minutes using a hydrothermal co-bath reduced pressure distillation method;

[0067] The remaining liquid was centrifuged, and the precipitate was washed with deionized water and finally freeze-dried to obtain CL-20 solid.

[0068] The hydrothermal co-bath method can effectively remove impurities and improve the purity of CL-20. The purity of the obtained CL-20 solid can reach 37.87%, and it can be further purified by recrystallization through the anti-solvent method and put into industrial use.

[0069] Example 1: CL-20 recovery under optimal conditions

[0070] This example is intended to demonstrate the method of recovering CL-20 from strong acid waste liquid using NKA-2 resin under optimal conditions. Figure 1 shown.

[0071] 1. Adsorption: Weigh 10 g of NKA-2 type super cross-linked polystyrene resin and add it to 100 mL of strong acid waste liquid (HNO3 concentration is 50%) containing CL-20 (concentration is 100 mg / L); place the mixture in a 25°C constant temperature water bath shaker and shake at a speed of 150 rpm for 6 hours.

[0072] 2. Desorption: After adsorption is completed, use a vacuum filtration device to separate the adsorption-saturated NKA-2 resin from the waste liquid; transfer the adsorption-saturated resin to a clean conical flask, add 100 mL of ethyl acetate as a desorbent; place the conical flask in a 25°C constant temperature water bath shaker and shake at 150 rpm for 30 minutes for desorption.

[0073] 3. Cyclic adsorption-desorption: The desorbed NKA-2 resin is used again to adsorb new strong acid waste liquid containing CL-20, and steps 1 and 2 are repeated for 3 cycles. New strong acid waste liquid is used for each cycle, and ethyl acetate is not replaced.

[0074] 4. Recovery: After three cycles, the ethyl acetate solution enriched with CL-20 was mixed with an equal volume (about 100 mL) of deionized water and transferred to a round-bottom flask. Connect a vacuum distillation device and perform vacuum distillation at 80°C in a water bath for 30 minutes until the ethyl acetate is basically distilled.

[0075] Example 2: Effect of different adsorbents on CL-20 adsorption

[0076] Step 1: Dosage Optimization

[0077] Take 100ml of diluted waste acid in a 250ml conical flask, add 0.2, 0.5, 0.7, 1, 1.2, 1.5, 2g of resin respectively, and oscillate on a shaker at 25 degrees Celsius and 200rpm for 12 hours to ensure that CL-20 is fully adsorbed on the resin. After the adsorption, filter the solution through a 0.22μm filter membrane and use double ternary liquid chromatography to determine the remaining CL-20 concentration in the solution. To ensure the accuracy of the experiment, three parallel samples are made for each experiment. Langmuir isotherm adsorption equation, Freundlich isotherm adsorption equation and Langmuir-Freundlich isotherm adsorption model are usually used to fit the effect of adsorbent dosage on adsorption performance.

[0078] The results show that if Figure 2As shown in (a), (c), (e), and (g), (a), (c), (e), and (g) are different dosages of DA201-C, NKA-2, D730, and D121 resins, respectively. With the increase of adsorbent dosage, the removal rate of CL-20 gradually increases, but the unit adsorption amount gradually decreases. When the adsorbent dosage is 10g / l, the removal rate and recovery rate of CL-20 reach the best balance. The Freundlich model can better fit the adsorption process, indicating that CL-20 is adsorbed in multiple layers on the resin.

[0079] Step 2: Optimize adsorption time

[0080] This example aims to study the effect of different adsorption times on the adsorption rate of CL-20.

[0081] Take 200 ml of waste acid into a conical flask, add the optimal dosage of resin, and oscillate in a shaker at a constant temperature of 25°C and 200 rpm. Take 2 ml of sample at 5, 15, 30, 45, 60, 120, 180, 240, 360, 480, 600, and 720 min, respectively, and filter with a 0.22 μm filter head. Determine the concentration of CL-20 in the waste acid using a dual ternary liquid chromatograph.

[0082] The results show that if Figure 2 As shown in (b), (d), (f), and (h), (b), (d), (f), and (h) are the adsorption times of DA201-C, NKA-2, D730, and D121 resins, respectively. As the adsorption time increases, the removal rate of CL-20 gradually increases, but the adsorption rate gradually decreases. When the adsorption time is 6 hours, the removal rate of CL-20 reaches a high level, and the adsorption time is relatively economical and reasonable. The pseudo-second-order kinetic model can better fit the adsorption process, indicating that the adsorption of CL-20 by the resin is a chemical process.

[0083] Combining steps 1 and 2, it can be seen that NKA-2 resin has the best adsorption effect on CL-20, and NKA-2 resin can be used for analytical and adsorption cycle experiments.

[0084] Example 3: Effect of desorption on CL-20 recovery

[0085] Step 1: The influence of the type of analytical adjuvant on the analytical adjuvant of CL-20

[0086] Methanol, ethanol, acetone and ethyl acetate were selected as desorption solutions. 100 ml of industrial waste acid and 1 g of the resin with the best adsorption effect were added to a 250 ml conical flask, and adsorbed in a shaker at 25 ° C and 200 rpm for 8 hours, and the residual concentration of CL-20 in the waste acid was determined. Then, the waste acid was filtered to remove it, and 10 ml of desorption solution was added to the resin. Desorption was carried out under the same conditions for 12 hours, and the concentration of CL-20 in the desorption solution was filtered and determined.

[0087] The results show that if Figure 3 As shown in (a), the desorption efficiency of CL-20 by different desorbents is different. Ethyl acetate has the highest desorption efficiency, followed by acetone. The desorption efficiencies of methanol and ethanol are relatively low.

[0088] Step 2: Effect of the analysis time on the analysis of CL-20

[0089] Add 4g of resin to 400ml of waste acid solution and adsorb for 12h to reach equilibrium. After removing the waste acid and drying, add 40ml of desorption solution. Take 0.5ml of sample at 5, 15, 30, 45, 60, 120, 180, 240, 360, 480, 600, and 720min respectively and filter with a 0.22μm filter head to determine the concentration of CL-20 in the solution.

[0090] The results show that if Figure 3 As shown in (b), the desorption rate increases with the extension of time, and the desorption equilibrium can be reached in 30 minutes, and the desorption rate is above 95%.

[0091] Step 3: Effect of cycle number on CL-20 analytical attachment

[0092] Add 200 ml of waste acid solution and 2 g of resin into a 250 ml conical flask for adsorption. After equilibrium, remove the waste acid and add 20 ml of desorption solution for desorption. After equilibrium, retain the resin and desorption solution, replace the waste acid solution for the next cycle, and wash the resin with deionized water after each cycle.

[0093] like Figure 3 As shown in (c), the optimal number of cycles is 3 times, and the CL-20 concentration is as high as 2.6 g / l, which has a high recovery value.

[0094] Example 4: Effect of vacuum distillation on CL-20 recovery

[0095] This example aims to study the effect of vacuum distillation on CL-20 recovery.

[0096] Add 40ml of the recycled CL-20-ethyl acetate solution and 40ml of deionized water to a 250ml round-bottom flask, heat it in a water bath at 80°C, and filter it with a vacuum pump. The evaporated ethyl acetate vapor is condensed through a condenser and collected for reuse. Stop heating when the liquid in the round-bottom flask is no longer boiling, and let it stand for 2 hours until the remaining liquid returns to room temperature. Then transfer the solid-liquid mixture in the round-bottom flask to a centrifuge tube, centrifuge it at 8000rpm for 5min, remove the supernatant, and wash the lower layer of solid with deionized water three times. Finally, dry the recovered solid in a freeze dryer for 12h.

[0097] The results show that if Figure 4 As shown in (a), the original waste acid contains a large amount of other substances besides CL-20. Through the adsorption-desorption-cycle process, CL-20 is purified and enriched, as shown in Figure 4 (b) As shown; the overall recovery rate of CL-20 through evaporation and crystallization is 58.25%. Ethyl acetate will increase the solubility of CL-20 in water after being slightly soluble in water. The theoretical recovery rate of CL-20 is 92.4% calculated by measuring the content of CL-20 in the supernatant after centrifugation, and the rest is lost during operation.

[0098] The purity of CL-20 in the recovered solid is 37.87%±0.50%. The recovered CL-20 can be further purified by recrystallization using an anti-solvent method and then put into industrial use.

[0099] Another embodiment of the present invention discloses a system for recovering CL-20 from strong acid waste liquid using a macroporous adsorption resin, comprising: an adsorption module, a desorption module and a recovery module;

[0100] The adsorption module includes a constant temperature water bath shaker for adsorbing CL-20 in the strong acid waste liquid;

[0101] The desorption module includes a vacuum filtration device and a constant temperature water bath shaker, which are used to desorb the saturated resin;

[0102] The recovery module includes a vacuum distillation device and a freeze dryer, and is used for recovering CL-20.

[0103] Compared with the prior art, the beneficial effects of the present invention include at least:

[0104] The present invention discloses an efficient, economical and environmentally friendly technical solution for recovering CL-20 by using macroporous adsorption resin, which includes four steps of adsorption, desorption, cyclic adsorption-desorption and recovery, and can effectively solve the problem of treating strong acid waste liquid containing CL-20, while realizing the recovery and utilization of valuable chemicals, and highlighting the advantages of the present invention compared with the prior art:

[0105] 1. High recovery rate: The recovery rate of CL-20 can reach more than 58.25%, and the recovery rate is even higher in actual industrial applications.

[0106] 2. Low cost: Use cheap and readily available adsorbents and desorbents to reduce production costs.

[0107] 3. Easy to operate: The operation steps are simple and easy to control, without complicated equipment and operation.

[0108] 4. Environmentally friendly: Reduce the pollution of CL-20 to the environment, in line with the concept of sustainable development.

[0109] 5. CL-20 enrichment can be achieved: Through cyclic adsorption-desorption operation, CL-20 can be effectively enriched and the recovery efficiency can be improved.

[0110] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents, and any modifications or equivalent replacements that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A method for recovering CL-20 from strong acid waste liquid using a macroporous adsorption resin, characterized in that: The following steps are involved: Resin screening: Select macroporous adsorption resins with set physical and chemical properties; Adsorption: Add macroporous adsorption resin into the strong acid waste liquid containing CL-20, and perform adsorption reaction under set conditions; Desorption: After the adsorption is completed, the saturated resin is separated from the strong acid waste liquid, and then the desorbent is used to treat the saturated resin under set conditions; Cyclic adsorption-desorption: the desorbed resin is put back into the strong acid waste liquid containing CL-20 for adsorption, and the adsorption-desorption process is repeated for multiple cycles; Recovery: The solution containing CL-20 obtained by adsorption-desorption is distilled, centrifuged and dried to obtain CL-20 solid.

2. The method for recovering CL-20 from strong acid waste liquid by using a macroporous adsorption resin according to claim 1, characterized in that: The resin with set physical and chemical properties means that the resin needs to withstand a strong acidic environment with a pH value less than 1.

3. The method for recovering CL-20 from strong acid waste liquid by using a macroporous adsorption resin according to claim 1, characterized in that: The adsorption setting conditions are as follows: placing the resin and the strong acid waste liquid mixture containing CL-20 in a constant temperature water bath shaker at room temperature, and oscillating and adsorbing at a speed of 0-200 rpm for 0-6 hours.

4. The method for recovering CL-20 from strong acid waste liquid by using a macroporous adsorption resin according to claim 1, characterized in that: The desorption process specifically comprises: A vacuum filtration device is used to separate the adsorption saturated resin from the strong acid waste liquid; The adsorption saturated resin is immersed in the desorption agent and the desorption operation is carried out under the set conditions.

5. The method for recovering CL-20 from strong acid waste liquid by using a macroporous adsorption resin according to claim 4, characterized in that: The analytical adjuvant is any one of methanol, ethanol, acetone or ethyl acetate.

6. The method for recovering CL-20 from strong acid waste liquid by using a macroporous adsorption resin according to claim 4, characterized in that: The setting conditions are as follows: placing the adsorption saturated resin and the adsorbent in a reaction container, and oscillating and adsorbing at a rotation speed of 0-200 rpm for 0-30 minutes in a constant temperature water bath shaker.

7. The method for recovering CL-20 from strong acid waste liquid by using a macroporous adsorption resin according to claim 1, characterized in that: In the cyclic adsorption-desorption process, new CL-20 strong acid waste liquid was used in each cycle, and the resin was cleaned with deionized water without replacing the desorbent.

8. The method for recovering CL-20 from strong acid waste liquid by using a macroporous adsorption resin according to claim 1, characterized in that: The recycling process includes: The desorbent solution containing CL-20 is mixed with an equal volume of deionized water, and treated under set conditions to remove the desorbent to obtain a solution containing CL-20; The solution containing CL-20 was centrifuged, and the precipitate was washed with deionized water, and finally freeze-dried to obtain CL-20 solid.

9. The method for recovering CL-20 from strong acid waste liquid by using a macroporous adsorption resin according to claim 8, characterized in that: The set conditions are to adopt a water-heat co-bath reduced pressure distillation method and distill at 80°C to 90°C for 30 to 40 minutes.

10. A system for recovering CL-20 from strong acid waste liquid by using a macroporous adsorption resin, which implements a method for recovering CL-20 from strong acid waste liquid by using a macroporous adsorption resin according to any one of claims 1 to 9, characterized in that: include: Adsorption module, desorption module and recovery module; The adsorption module includes a constant temperature water bath shaker for adsorbing CL-20 in the strong acid waste liquid; The desorption module includes a vacuum filtration device and a constant temperature water bath shaker, which are used to desorb the saturated resin; The recovery module includes a vacuum distillation device and a freeze dryer, and is used for recovering CL-20.

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