Method for treating waste water from production of a heat-sensitive developer F-103

Abstract

The present application belongs to the technical field of water treatment, and relates to a heat-sensitive color developing agent F-103 production wastewater treatment method. The present application performs multistage treatment on the wastewater. First, an alkaline chemical separation reaction is performed on the wastewater to remove part of the acidic polar organic matter 3-p-tolylsulfonylureido phenol, p-toluenesulfonic acid and the like in the water. Then, an acid chemical separation reaction is performed to further remove the alkaline polar organic matter intermediate MAPOTs and the like in the water. Subsequently, an adsorption reaction is performed using activated carbon to further remove the organic matter and inorganic impurities in the water. Finally, evaporation and concentration are performed to recover the salt sodium chloride. The wastewater treatment of the present application recovers the salt sodium chloride in the wastewater as a resource under the premise of solving the toxicity problem of the organic matter in the wastewater, and realizes the harmless treatment and the reduction of hazardous waste of the wastewater.

Description

Technical Field

[0001] This invention relates to the field of chemical wastewater treatment technology, specifically to a process for treating wastewater from the production of the thermosensitive colorimetric agent F-103. Background Technology

[0002] Thermosensitive developer F-103 (i.e., 3-(3-tolylureo)phenyl-4-methylbenzenesulfonate, hereinafter referred to as F-103) is mainly used in the field of photosensitive materials, primarily as a developer for thermal paper, and is one of the key components of thermal recording materials. It plays a crucial role in the production of thermal paper, improving the paper's sensitivity to heat and pressure, providing high optical density and clarity in recorded images, and enhancing the sensitivity, thermal stability, luminescence, and other properties of thermal recording paper.

[0003] The F-103 structure is as follows:

[0004] Currently, F-103 is mainly prepared from p-toluenesulfonyl isocyanate, m-aminophenol, and p-toluenesulfonyl chloride as raw materials, through reaction, filtration, refining, and drying. The production process of F-103 generates a large amount of wastewater, which is characterized by high color, high COD, high aniline content, high toxicity, high salinity, carcinogenicity, mutagenicity, and poor biodegradability, making it difficult to treat.

[0005] Currently, there is no clear treatment method for F-103 production wastewater in domestic and international literature. Domestic treatment methods for wastewater from the production of heat-sensitive materials adopt a combined wastewater treatment process that combines physicochemical pretreatment with biochemical treatment, mainly divided into physical methods and chemical methods. Physical methods include adsorption, sedimentation, filtration, and evaporation; chemical methods include complexation, flocculation, activated carbon adsorption, Fenton oxidation, and other processes.

[0006] Furthermore, CN107021537A discloses a complex extraction method for treating toxic pollutants containing 2-naphthol, 2,3-acid, etc., under acidic conditions. The complex extractant comprises a complexing agent, a co-solvent, and a diluent. The complexing agent is selected from one or two of tributyl phosphate, diisooctyl phosphate, or triisobutylphosphine sulfide; the co-solvent is a C6-C18 monohydric alcohol; and the diluent is selected from one or two of xylene or sulfonated kerosene. The CN107021537A also discloses regenerating the complex extractant loaded with the extract phase using an alkaline solution to obtain an enriched phase and a regenerated complex extractant. However, since the pollutants in F-103 wastewater, such as 3-p-toluenesulfonylaminoureaphenol, p-toluenesulfonic acid, and intermediate MAPOTs, are different from 2-naphthol and 2,3-acid, the complex extractant has no obvious effect. Furthermore, F-103 wastewater also contains alkaline polar organic intermediates such as MAPOTs, which cannot be treated by a single process.

[0007] Therefore, targeted pretreatment of F-103 production wastewater to address the toxicity of organic matter while simultaneously recovering salts from the wastewater is crucial for wastewater treatment. Summary of the Invention

[0008] This invention addresses the shortcomings of existing technologies, solves the toxicity problem of organic matter in wastewater, and simultaneously recovers salts from wastewater for resource utilization, achieving wastewater harmlessness and hazardous waste reduction. A novel wastewater treatment method using the thermosensitive colorimetric reagent F-103 has been developed. This method, considering the composition of the wastewater pollutants, recovers sodium chloride as a byproduct while removing organic pollutants. The treatment process includes alkaline chemical separation, acidic chemical separation, adsorption, and concentration.

[0009] A method for treating wastewater from the production of thermosensitive colorimetric reagent F-103, characterized by comprising the following steps:

[0010] (1) Alkaline chemical separation: Add an acidic solution to the F-103 production wastewater to adjust the pH to 2-4, add an alkaline agent to react, and after the reaction is completed, perform a layering treatment to obtain an upper separated phase and a lower aqueous phase. The lower aqueous phase is reserved for later use. Add an alkaline desorption agent to the obtained separated phase to recover the alkaline agent in the separated phase. After the reaction is completed, allow it to stand and separate. The upper layer is the recovered alkaline agent, which can be reused, and the lower layer is an acidic organic salt solution.

[0011] (2) Acidic chemical separation: Add an alkaline solution to the lower aqueous phase in step (1) to adjust the pH to neutral, add an acidic reagent to react, and after the reaction is completed, perform a layering process to obtain an upper separated phase and a lower aqueous phase. The lower aqueous phase is reserved for later use. Add an acidic eluent to the obtained separated phase to recover the acidic reagent in the separated phase. After the reaction is completed, allow it to stand and separate. The upper layer is the recovered acidic reagent, which can be reused, and the lower layer is an alkaline organic salt solution.

[0012] (3) Adsorption: Add adsorbent to the lower aqueous phase in step (2) to remove some of the remaining toxic organic matter and decolorize the wastewater, and filter to obtain filtrate for later use;

[0013] (4) Concentration: Evaporate and crystallize the filtrate from step (3) to obtain sodium chloride by-product and distilled water;

[0014] The alkaline reagent in step (1) includes: a reactant, a cosolvent, and a diluent, wherein the reactant is trioctylphosphine, dialkyl phosphate ester, or dialkyl alkyl phosphonate ester, the cosolvent is an alcohol compound with a carbon chain of 8-20, and the diluent is aviation kerosene or diesel.

[0015] The inventors discovered that the wastewater from the F-103 production mainly contains toxic organic compounds such as 3-p-toluenesulfonylaminoureaphenol, p-toluenesulfonic acid, and intermediate MAPOTs, exhibiting high concentrations of toxic organic pollutants and high chemical oxygen demand (COD). This results in a significant impact on both acidic and alkaline reagents. However, due to the differences in the main active ingredients of acidic and alkaline reagents, alkaline reagents have a higher load-bearing capacity and can withstand higher levels of toxic organic pollutants. In contrast, acidic reagents may exhibit emulsification failure when faced with high concentrations of pollutants. Therefore, this invention selects to first perform alkaline chemical separation to remove acidic polar organic compounds, thereby reducing the load, before proceeding with acidic chemical separation.

[0016] Furthermore, in order to further remove organic matter and decolorize the wastewater, an appropriate amount of activated carbon is added to the acidic chemically separated water for adsorption, thereby improving the quality of the subsequently produced sodium chloride.

[0017] Since the pH of the wastewater from F-103 production is relatively high, generally between 8 and 12, if the pH is too high, it will cause the alkaline reagent to emulsify and become inactive during alkaline chemical separation. However, if the pH is too low, it will reduce the reaction effect and increase the amount of acidic solution used. Therefore, in this application, an acidic solution needs to be added before alkaline chemical separation to bring the pH of the wastewater to a range of 2-4. Preferably, in step 1, the acidic solution is a hydrochloric acid solution with a mass fraction of 10%-35%.

[0018] The inventors discovered that phenolic and sulfonic acid substances such as 3-p-toluenesulfonylaminoureaphenol and p-toluenesulfonic acid in wastewater can be separated from water by using one or more of the following alkaline reagents: trioctylphosphine, dialkyl phosphate esters, and dialkyl alkyl phosphonates. These reagents not only possess significant hydrophobicity, reducing reagent loss due to water dissolution, but also combine with phenolic and sulfonic acid substances like 3-p-toluenesulfonylaminoureaphenol and p-toluenesulfonic acid to form hydrophobic groups, thus achieving the separation of pollutants from water. Choosing alcohols with carbon chains of 8-20 as co-solvents can enhance the interaction between pollutants and reagents, improving the efficiency of alkaline chemical separation. Selecting aviation kerosene or diesel oil as diluents can alter the density of the alkaline reagent, accelerating the separation rate of the reagent and water and shortening the reaction time.

[0019] Preferably, in step 1, the alkaline reagent is prepared by mixing the reactant, cosolvent, and diluent in a volume ratio of (1-4):(1-2):(4-8). If the reactant ratio is too high, the viscosity of the alkaline reagent will increase, making it difficult to separate from the wastewater; if it is too low, the removal efficiency of phenols and sulfonic acids such as 3-toluenesulfonylaminoureaphenol and p-toluenesulfonic acid will decrease. If the cosolvent ratio is too high, the cost of the alkaline reagent will increase dramatically; if it is too low, the solubility of the hydrophobic groups formed in the alkaline reagent will decrease, leading to reagent failure. If the diluent ratio is too high, the reactant ratio will decrease, reducing the removal efficiency of acidic organic substances such as 3-toluenesulfonylaminoureaphenol and p-toluenesulfonic acid; if it is too low, the viscosity of the alkaline reagent will increase, making it difficult to separate from water.

[0020] Preferably, in step 1, the volume ratio of the alkaline agent to the F-103 production wastewater is 10%-35%. A higher volume ratio increases the cost of chemical separation and the loss of the alkaline agent, while a lower ratio leads to saturation of the bound hydrophobic groups and a decrease in the removal efficiency of acidic organic compounds such as 3-toluenesulfonylaminoureaphenol and p-toluenesulfonic acid. The reaction temperature is 10-40℃; a higher temperature causes the alkaline agent to volatilize, increasing usage costs, while a lower temperature reduces the reaction rate and results in poor reaction performance. The preferred reaction temperature is 20-30℃. The reaction time is 20-50 minutes; a shorter time results in incomplete reaction and incomplete removal of toxic organic compounds, while a longer time causes the alkaline agent to lose its activity, increasing usage costs. The preferred reaction time is 30-40 minutes.

[0021] Preferably, in step 1, the alkaline eluent is a sodium hydroxide solution with a mass fraction of 10%-20%. If the concentration is too low, the separated phase will not be completely eluented, and if the concentration is too high, the recovered reagent will be emulsified and deactivated. The volume ratio of the eluent to the separated phase is 1:(6-10). If too much eluent is added, the waste liquid volume will increase, increasing the treatment cost. If too little eluent is added, the alkaline reagent will not be completely recovered.

[0022] Preferably, in step 1, the alkaline agent recovery conditions are a reaction temperature of 30-50℃. Too high a temperature will cause the alkaline agent to volatilize, increasing the cost of use; too low a temperature will prevent the alkaline agent from being completely recovered. The preferred reaction temperature is 40-45℃. The reaction time is 20-40 minutes. Too short a time will result in an incomplete reaction, and toxic organic matter will not be completely removed; too long a time will cause the alkaline agent to lose its activity, increasing the cost of use. The preferred reaction time is 25-30 minutes.

[0023] The inventors discovered that after alkaline chemical separation in step (1), the wastewater mainly contains organic intermediates such as MAPOTs, which can be separated by adding acidic agents. However, after alkaline chemical separation in step (1), the pH of the wastewater is 2-4, which is low and will reduce the reaction effect of acid separation. It is necessary to add alkaline solution to adjust the pH of the wastewater. However, if the pH is too high, it will cause the acidic agents to emulsify and deactivate. The preferred pH range is 6-8. Preferably, in step 2, the alkaline solution is a sodium hydroxide solution with a mass fraction of 10-32%.

[0024] The inventors discovered that, for organic intermediates MAPOTs in wastewater, the acidic reagent can utilize one or more of nonanoic acid, 2-methyl-8-hydroxyquinoline, or 5,8-dinonyl-2-naphthalenesulfonic acid as reactants. These reactants have high hydrophobicity, reducing the loss of reactants in water dissolution. They can also combine with MAPOTs to form hydrophobic groups, thereby achieving the separation of pollutants from water. The cosolvent is an alcohol compound with a carbon chain of 8-20, which can enhance the interaction between pollutants and reactants and improve the efficiency of acidic chemical separation. The diluent is aviation kerosene or diesel oil, which can change the density of the acidic reagent, accelerate the separation rate of the reagent and water, and shorten the reaction time. Preferably, in step 2, the acidic agent is composed of reactant, cosolvent, and diluent mixed in a volume ratio of (1-3):(1-4):(3-8). If the reactant ratio is too high, the viscosity of the acidic agent will increase, making it difficult to separate from the wastewater; if it is too low, the removal efficiency of organic intermediates MAPOTs will decrease. If the cosolvent ratio is too high, the cost of the acidic agent will increase dramatically; if it is too low, the solubility of the hydrophobic groups formed in the acidic agent will decrease, leading to agent failure. If the diluent ratio is too high, the proportion of reactant will decrease, reducing the removal efficiency of intermediates MAPOTs; if it is too low, the viscosity of the acidic agent will increase, making it difficult to separate from water.

[0025] Preferably, in step 2, the volume ratio of the acidic agent to F-103 wastewater is 10%-35%. A higher volume ratio increases the cost of chemical separation and the loss of the acidic agent, while a lower ratio leads to saturation of the bound hydrophobic groups and a decrease in the removal efficiency of intermediate MAPOTs. The reaction temperature is generally 10-40℃. Too high a temperature causes the acidic agent to volatilize, increasing usage costs; too low a temperature leads to a decreased reaction rate and extremely poor reaction results. The preferred reaction temperature is 20-30℃. The reaction time is 20-50 minutes. Too short a time leads to incomplete reaction and incomplete removal of toxic organic matter, while too long a time causes the acidic agent to lose its activity, increasing usage costs. The preferred reaction time is 30-40 minutes.

[0026] Ideally, in step 2, the acidic eluent is a hydrochloric acid solution with a mass fraction of 10-20%. Too low a concentration will result in incomplete eluent removal of the separated phase, while too high a concentration will result in emulsification and deactivation of the recovered reagent. The volume ratio of the eluent to the separated phase is 1:(6-10). If too much eluent is added, the waste liquid volume will increase, increasing the treatment cost. If too little eluent is added, the alkaline reagent will not be fully recovered.

[0027] Preferably, in step 2, the acidic agent recovery conditions are a reaction temperature of 30-50°C. Too high a temperature will cause the acidic agent to volatilize, increasing the cost of use, while too low a temperature will not allow the acidic agent to be completely recovered. The preferred reaction temperature is 40-45°C. The reaction time is 20-40 minutes. Too short a time will result in an incomplete reaction, and toxic organic matter will not be completely removed. Too long a time will cause the acidic agent to lose its activity, increasing the cost of use. The preferred reaction time is 25-30 minutes.

[0028] Preferably, in step 3, the adsorbent used is activated carbon, and the reaction temperature is 10-40℃. Too high a temperature will increase the treatment cost, and the reaction efficiency will not be significantly different from the preferred temperature. Too low a temperature will cause the reaction rate to decrease, affecting the reaction effect. The preferred reaction temperature is 20-25℃. The reaction time is 20-40 min. Too long a time will not have a significant difference in treatment effect, and too short a time will affect the reaction effect. The preferred reaction time is 25-30 min.

[0029] Compared with the prior art, the beneficial effects of the present invention are:

[0030] (1) The problem of wastewater toxicity has been solved. Compared with the traditional physical-chemical combined treatment process, this process has a higher removal efficiency for organic pollutants in wastewater. First, alkaline chemical separation targets acidic polar organic compounds (such as phenols and carboxylic acids) in wastewater. The alkaline agent combines with the acidic polar groups of organic compounds in the wastewater to form new macromolecular organic compounds that are insoluble in the aqueous phase, thereby separating the target substances from the wastewater. Acidic polar organic compounds in wastewater are removed. In this process, the COD (chemical oxygen demand) removal rate of wastewater reaches more than 35%, and the color of wastewater changes from black to yellow.

[0031] Next, acidic chemical separation is used to target residual alkaline polar organic intermediates such as MAPOTs in the wastewater. The acidic agent combines with the alkaline polar groups of organic matter in the wastewater to form new macromolecular organic compounds insoluble in the aqueous phase, thereby separating the target substances from the wastewater. After the alkaline polar organic matter in the wastewater is removed, the COD removal rate reaches over 80%, the aniline removal rate is over 85% (MAPOTs intermediates contain aniline groups; detecting the content of aniline substances in the water can reflect the removal status of MAPOTs), and the phenol removal rate is over 85%. The wastewater color changes from yellow to light yellow.

[0032] Subsequently, activated carbon adsorption was used for further treatment of the wastewater. Due to its porous structure, large specific surface area, and strong adsorption capacity, activated carbon adsorbed and precipitated the remaining toxic organic matter in the wastewater, thus removing it from the wastewater system. After this process, most of the toxic organic matter in the wastewater was removed, with COD removal rates exceeding 90%, aniline removal rates exceeding 93%, and phenol removal rates exceeding 90%. The wastewater changed from pale yellow to nearly colorless.

[0033] Finally, the adsorption effluent is concentrated to remove salts from the wastewater. The COD removal rate of the distillate reaches over 98%, the aniline removal rate is over 99% (almost none), the phenol removal rate is over 99% (almost none), and the effluent is colorless.

[0034] (2) Waste salt recycling. This invention can recycle and reuse the sodium chloride salt precipitated in the wastewater from the production of the thermosensitive colorimetric reagent F-103. The sodium chloride salt does not need to be treated again, thus reducing the amount of hazardous waste generated. Attached Figure Description

[0035] Figure 1 Here is a flow chart of a wastewater treatment process for the production of the thermosensitive colorimetric agent F-103 according to the present invention: Detailed Implementation

[0036] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0037] Furthermore, the technical solutions of the various embodiments of the present invention can be combined with each other, but only if they are feasible for those skilled in the art. If the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention.

[0038] <Example 1>

[0039] A method for treating wastewater from the production of the thermosensitive colorimetric reagent F-103 is disclosed. The wastewater is taken from the intermediate production workshop of a photosensitive chemical plant in Shenyang. The water quality is as follows: pH=12, COD: 48050mg / L, aniline: 6472mg / L, phenols: 5730mg / L, black.

[0040] (1) Preparation of alkaline reagent: Take 100ml of trioctylphosphine, 100ml of dialkyl phosphate ester, 200ml of isomeric alcohol and 600ml of aviation kerosene and mix them to obtain 1000ml of alkaline reagent.

[0041] (2) Preparation of acidic reagent: Take 300ml nonanoic acid, 200ml isomeric alcohol and 500ml aviation kerosene and mix them to obtain 1000ml acidic reagent;

[0042] (3) Alkaline chemical separation: Take 3000ml of wastewater, add 25% hydrochloric acid solution to adjust pH=2, then add 600ml of alkaline reagent, and react fully at 20℃ for 30min; let stand to separate the layers, the upper layer is the separated phase, and the lower layer is the treated effluent; the reaction time of alkaline chemical separation includes the time for full mixing and complete reaction.

[0043] (4) Alkaline agent regeneration: Add 18% sodium hydroxide solution to the separated phase, wherein the volume ratio of the separated phase to the sodium hydroxide solution is 6:1. React fully for about 30 minutes under a water bath at 40°C. After standing and separating, the lower layer is an acidic organic salt solution and the upper layer is the recovered alkaline agent, which can be used for recycling. The reaction time for alkaline agent recovery includes the time for complete mixing and reaction.

[0044] (5) Acidic chemical separation: Take 3000ml of alkaline chemical separation effluent, add 20% sodium hydroxide solution to adjust pH=7, then add 600ml of acidic reagent, and react fully at 20℃ for 30min; let stand to separate the layers, the upper layer is the separation phase, and the lower layer is the treated effluent; the reaction time of acidic chemical separation includes the time for full mixing and complete reaction.

[0045] (6) Regeneration of acidic reagent: Add a 12% hydrochloric acid solution to the separated phase, wherein the volume ratio of the separated phase to the hydrochloric acid solution is 8:1. React fully for about 30 minutes under a 40°C water bath. After standing and separating, the lower layer is an alkaline organic salt solution and the upper layer is the recovered acidic reagent, which can be used for recycling. The reaction time for acidic reagent recovery includes the time for complete mixing and reaction.

[0046] (7) Adsorption and evaporation: Take 3000ml of alkaline chemically separated water and add 0.1% of its mass of activated carbon solid. React fully at 20℃ for 30min. After filtration, the adsorbed water is evaporated and concentrated to obtain sodium chloride. According to the relevant requirements of the "Identification Standard for Hazardous Waste" (GB 5085.1-GB5085.7), it can meet the standard for by-product salt. From the detection indicators of the adsorbed water in Table 1, it can be seen that the COD removal rate of the wastewater reaches more than 90%, the removal rate of aniline substances, which reflects the removal of MAPOTS, reaches more than 96%, and phenols are almost completely removed. The mother liquor is recycled a certain number of times and then discharged as hazardous waste; the distillate is the final treated effluent.

[0047] Table 1. Treatment Results

[0048]

[0049] <Example 2>

[0050] A method for treating wastewater from the production of the thermosensitive color developer F-103 is disclosed. The wastewater is taken from the photosensitive material production workshop of a chemical plant in Hunan Province, and the water quality is as follows: pH=8, COD: 58880mg / L, aniline: 10062mg / L, phenols: 4880mg / L, brownish-black.

[0051] (1) Preparation of alkaline reagent: Take 200ml of trioctylphosphine, 200ml of isomerized alcohol and 600ml of aviation kerosene and mix them to obtain 1000ml of alkaline reagent;

[0052] (2) Preparation of acidic reagent: Take 100ml nonanoic acid, 100ml 5,8-dinonyl-2-naphthalenesulfonic acid, 200ml isomeric alcohol and 600ml aviation kerosene and mix them to obtain 1000ml acidic reagent;

[0053] (3) Alkaline chemical separation: Take 3000ml of wastewater, add 35% hydrochloric acid solution to adjust pH=3, then add 600ml of alkaline reagent, and react fully at 20℃ for 40min; let stand to separate the layers, the upper layer is the separated phase, and the lower layer is the treated effluent; the reaction time of alkaline chemical separation includes the time for full mixing and complete reaction.

[0054] (4) Alkaline agent regeneration: Add a 15% sodium hydroxide solution to the separated phase, wherein the volume ratio of the separated phase to the sodium hydroxide solution is 7:1. React fully for about 30 minutes under a water bath at 40°C. After standing and separating, the lower layer is an acidic organic salt solution and the upper layer is the recovered alkaline agent, which can be used for recycling. The reaction time for alkaline agent recovery includes the time for complete mixing and reaction.

[0055] (5) Acidic chemical separation: Take 3000ml of alkaline chemical separation effluent, add 30% sodium hydroxide solution to adjust pH=7, then add 900ml of acidic reagent, and react fully at 20℃ for 40min; let stand to separate the layers, the upper layer is the separated phase, and the lower layer is the treated effluent; the reaction time of acidic chemical separation includes the time for full mixing and complete reaction.

[0056] (6) Regeneration of acidic reagent: Add 15% hydrochloric acid solution to the separated phase, wherein the volume ratio of the separated phase to the hydrochloric acid solution is 6:1. React fully for about 40 minutes under a water bath at 40°C. After standing and separating, the lower layer is an alkaline organic salt solution and the upper layer is the recovered acidic reagent, which can be used for recycling. The reaction time for acidic reagent recovery includes the time for full mixing and complete reaction.

[0057] (7) Adsorption and evaporation: Take 3000ml of alkaline chemically separated water and add 0.1% of its mass of activated carbon solid. React fully at 25℃ for 30min. Then filter to obtain adsorbed water and evaporate and concentrate to obtain sodium chloride. According to the relevant requirements of the "Hazardous Waste Identification Standard" (GB 5085.1-GB5085.7), it can meet the standard of by-product salt. From the detection indicators of adsorbed water in Table 2, it can be seen that the removal effect of COD, aniline and phenol in wastewater is good. The mother liquor is recycled a certain number of times and then discharged as hazardous waste. The distilled water is the final treated effluent.

[0058] Table 2 Treatment Results

[0059]

[0060] <Example 3>

[0061] A method for treating wastewater from the production of thermosensitive colorimetric reagent F-103 is disclosed, which differs from Example 1 in that:

[0062] (1) Take 50ml of trioctylphosphine, 100ml of dialkyl phosphate ester, 200ml of isomeric alcohol and 650ml of aviation kerosene and mix them to obtain 1000ml of alkaline reagent.

[0063] (3) Add 800ml of alkaline reagent and react fully at 20℃ for 40min.

[0064] Table 3 Treatment Results

[0065]

[0066] <Example 4>

[0067] A method for treating wastewater from the production of thermosensitive colorimetric reagent F-103 is disclosed, which differs from Example 1 in that:

[0068] (1) Take 200ml of alkylphosphonic acid dialkyl ester, 200ml of isomeric alcohol and 600ml of aviation kerosene and mix them to obtain 1000ml of alkaline reagent.

[0069] (3) Adjust the pH to 4, and then add an alkaline agent.

[0070] Table 4 Treatment Results

[0071]

[0072] <Example 5>

[0073] A method for treating wastewater from the production of the thermosensitive colorimetric reagent F-103 is disclosed, which differs from Example 2 in that:

[0074] (2) Take 100ml nonanoic acid, 50ml 5,8-dinonyl-2-naphthalenesulfonic acid, 200ml isomeric alcohol and 650ml aviation kerosene and mix them to obtain 1000ml acidic reagent.

[0075] (5) Add 1000ml of acidic reagent and react fully at 20℃ for 40min.

[0076] In (6), the volume ratio of the separated phase to the hydrochloric acid solution is 8:1, and the reaction is carried out for 30 minutes under a water bath at 40°C.

[0077] Table 5 Treatment Results

[0078]

[0079] <Example 6>

[0080] A method for treating wastewater from the production of thermosensitive colorimetric reagent F-103 is disclosed, which differs from Example 1 in that:

[0081] (1) Take 20ml of trioctylphosphine, 30ml of dialkyl phosphate ester, 200ml of isomeric alcohol and 750ml of aviation kerosene and mix them to obtain 1000ml of alkaline reagent.

[0082] Table 6 Treatment Results

[0083]

[0084] Analysis revealed that the proportion of reactant in the acidic reagent was too low, leading to saturation of the hydrophobic groups formed by the acidic polar organic matter and the reactant, resulting in a decrease in the phenol removal rate.

[0085] <Example 7>

[0086] A method for treating wastewater from the production of thermosensitive colorimetric reagent F-103 is disclosed, which differs from Example 1 in that:

[0087] (3) The reaction temperature is 45℃.

[0088] Table 7 Treatment Results

[0089]

[0090] Analysis revealed that the reaction temperature for acid separation in step (3) was slightly higher, resulting in no improvement in treatment effect. The increase in temperature led to increased volatilization of alkaline reagents, increased reagent loss, and increased treatment costs.

[0091] <Example 8>

[0092] A method for treating wastewater from the production of thermosensitive colorimetric reagent F-103 is disclosed, which differs from Example 1 in that:

[0093] In (4), the reaction temperature is 25℃.

[0094] Table 8 Treatment Results

[0095]

[0096] Table 8 shows the treatment effect of the alkaline reagent cycle after 10 alkaline chemical separations. Analysis shows that because the reaction temperature of the alkaline reagent regeneration in step (3) is slightly lower, the acidic polar organic matter is not completely decomposed by the alkaline reagent. The organic matter is continuously enriched in the alkaline reagent, and finally the removal efficiency of the alkaline reagent for phenols decreases during the recycling process.

[0097] <Example 9>

[0098] A method for treating wastewater from the production of the thermosensitive colorimetric reagent F-103 is disclosed, which differs from Example 2 in that:

[0099] (2) Take 200ml of di(2-ethylhexyl)phosphoric acid, 200ml of isomeric alcohol and 600ml of aviation kerosene and mix them to obtain 1000ml of acidic reagent.

[0100] Table 9 Treatment Results

[0101]

[0102] Analysis revealed that the use of a different compound reagent than that in Example 2 resulted in the failure to remove most of the aniline substances from the wastewater, leading to a noticeable yellow color in the subsequently evaporated sodium chloride salt and poor salt quality.

[0103] <Example 10>

[0104] A method for treating wastewater from the production of the thermosensitive colorimetric reagent F-103 is disclosed, which differs from Example 2 in that:

[0105] (2) Take 200ml of dioctylphosphic acid, 200ml of isomeric alcohol and 600ml of aviation kerosene and mix them to obtain 1000ml of acidic reagent.

[0106] Table 10 Processing Results

[0107]

[0108] Analysis revealed that the use of dioctylphosphoric acid as an acidic reagent resulted in poor efficiency in binding alkaline polar organic compounds such as intermediates MAPOTs into hydrophobic groups, thus leading to a decrease in the removal rate of aniline compounds.

[0109] <Example 11>

[0110] A method for treating wastewater from the production of the thermosensitive colorimetric reagent F-103 is disclosed, which differs from Example 2 in that:

[0111] (3) The reaction temperature is 5℃ and the reaction time is 5min.

[0112] Table 11 Treatment Results

[0113]

[0114] Analysis revealed that the low reaction temperature during alkaline chemical separation resulted in insufficient activation energy, leading to a decrease in the reaction rate and a reduction in phenol removal rate.

[0115] <Comparative Example 1>

[0116] A method for treating wastewater from the production of thermosensitive colorimetric reagent F-103 is disclosed, which differs from Example 1 in that:

[0117] In terms of the treatment process, taking advantage of the alkaline pH of the wastewater (pH=12), the pH is first adjusted to 7 for acidic chemical separation, and then adjusted to 2 for alkaline chemical separation.

[0118] Table 12 Treatment Results

[0119]

[0120] Analysis revealed that the high concentration of toxic organic matter in the wastewater significantly impacted the acidic chemical separation process, causing the acidic reagents to become emulsified and ineffective. Consequently, the alkaline polar organic intermediates MAPOTs in the water were not effectively removed, resulting in a significant increase in COD of the adsorbed effluent and a decrease in the removal rates of aniline and phenols.

[0121] <Comparative Example 2>

[0122] A method for treating wastewater from the production of thermosensitive colorimetric reagent F-103 is disclosed, which differs from Example 1 in that:

[0123] (3) Adjust the pH of the wastewater to 1 and react at 20℃ for 40 min.

[0124] Table 13 Treatment Results

[0125]

[0126] Analysis revealed that the adjusted wastewater had an excessively low pH and an excessively high hydrogen ion concentration, which inhibited the formation of the reactant's combination with acidic polar organic matter, resulting in a significant decrease in the phenol removal rate.

[0127] <Comparative Example 3>

[0128] A method for treating wastewater from the production of thermosensitive colorimetric reagent F-103 is disclosed, which differs from Example 1 in that:

[0129] (3) Adjust the pH of the wastewater to 5 and react at 20℃ for 30 min.

[0130] Table 14 Treatment Results

[0131]

[0132] Analysis revealed that the pH of the adjusted wastewater was too high, which caused the alkaline reagent to lose its emulsification effect. As a result, the acidic polar organic matter in the water could not be significantly removed, the COD of the adsorbed water increased significantly, and the phenol removal rate decreased sharply.

[0133] <Comparative Example 4>

[0134] A method for treating wastewater from the production of thermosensitive colorimetric reagent F-103 is disclosed, which differs from Example 1 in that:

[0135] (1) Take 200ml of tributyl phosphate, 200ml of isomeric alcohol and 600ml of aviation kerosene and mix them to obtain 1000ml of alkaline reagent.

[0136] Table 15 Treatment Results

[0137]

[0138] Analysis revealed that using tributyl phosphate as a reactant in an alkaline reagent resulted in poor efficiency in binding acidic polar organic compounds such as 3-toluenesulfonylaminoureaphenol and p-toluenesulfonic acid into hydrophobic groups, leading to a significant decrease in phenol removal rate.

[0139] The above are merely specific embodiments of this application and are not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A method for treating wastewater from the production of the thermosensitive colorimetric reagent F-103, characterized in that, Includes the following steps: (1) Alkaline chemical separation: Add an acidic solution to the F-103 production wastewater to adjust the pH to 2-4, add an alkaline agent to react, and after the reaction is completed, perform a layering treatment to obtain an upper separated phase and a lower aqueous phase. The lower aqueous phase is reserved for later use. Add an alkaline desorption agent to the obtained separated phase to recover the alkaline agent in the separated phase. After the reaction is completed, allow it to stand and separate. The upper layer is the recovered alkaline agent, which can be reused, and the lower layer is an acidic organic salt solution. (2) Acidic chemical separation: Add an alkaline solution to the lower aqueous phase in step (1) to adjust the pH to neutral, add an acidic reagent to carry out the reaction, and perform a phase separation process after the reaction is completed to obtain an upper separated phase and a lower aqueous phase. The lower aqueous phase is reserved for later use. An acidic eluent is added to the obtained separated phase to recover the acidic reagent in the separated phase. After the reaction is completed, the phase is allowed to stand and separate. The upper layer is the recovered acidic reagent, which can be reused, and the lower layer is an alkaline organic salt solution. (3) Adsorption: Add adsorbent to the lower aqueous phase in step (2) to remove some of the remaining toxic organic matter and decolorize the wastewater, and filter to obtain filtrate for later use; (4) Concentration: Evaporate the filtrate from step (3) to crystallize it, and obtain sodium chloride by-product and distilled water; The alkaline reagent in step (1) includes: a reactant, a cosolvent, and a diluent, wherein the reactant is one or more of trioctylphosphine, dialkyl phosphate ester, and dialkyl alkyl phosphonate ester, the cosolvent is an alcohol compound with a carbon chain of 8-20, and the diluent is aviation kerosene or diesel. In step (1), the alkaline reagent is prepared by mixing the reactant, cosolvent, and diluent in a volume ratio of (1-4):(1-2):(4-8); In step (1), the volume ratio of the alkaline agent to the F-103 production wastewater is 10%-35%; the reaction temperature for adding the alkaline agent is 10-40℃, and the reaction time is 20-50min. In step (2), the acidic agent is a mixture of reactant, cosolvent, and diluent in a volume ratio of (1-3):(1-4):(3-8). The reactant is selected from one or more of nonanoic acid, 2-methyl-8-hydroxyquinoline, and 5,8-dinonyl-2-naphthalenesulfonic acid; the cosolvent is an alcohol compound with a carbon chain of 8-20; and the diluent is aviation kerosene or diesel oil. In step (2), the volume ratio of the acidic agent to the F-103 production wastewater is 10%-35%; the reaction temperature for adding the acidic agent is 10-40℃, and the reaction time is 20-50min. In step (3), the adsorbent is activated carbon, the reaction temperature is 10-40℃, and the reaction time is 20-40min.

2. The method for treating wastewater from the production of the thermosensitive colorimetric reagent F-103 according to claim 1, characterized in that, In step (1), the acidic solution is a hydrochloric acid solution with a mass fraction of 10%-35%.

3. The method for treating wastewater from the production of the thermosensitive colorimetric reagent F-103 according to claim 1, characterized in that, In step (1), the reaction temperature for adding alkaline reagent is 20-30℃ and the reaction time is 30-40min.

4. The method for treating wastewater from the production of the thermosensitive colorimetric reagent F-103 according to claim 1, characterized in that, In step (1), the alkaline eluent is a sodium hydroxide solution with a mass fraction of 10%-20% and a volume ratio of 1:(6-10) with the separation phase.

5. The method for treating wastewater from the production of the thermosensitive colorimetric reagent F-103 according to claim 4, characterized in that, In step (1), the reaction temperature for adding alkaline eluent to recover the separated phase is 30-50℃, and the reaction time is 20-40min.

6. The method for treating wastewater from the production of the thermosensitive colorimetric reagent F-103 according to claim 5, characterized in that, In step (1), the reaction temperature for adding alkaline eluent to recover the separated phase is 40-45℃, and the reaction time is 25-30min.

7. The method for treating wastewater from the production of the thermosensitive colorimetric reagent F-103 according to claim 1, characterized in that, In step (2), the alkaline solution is a sodium hydroxide solution with a mass fraction of 10-32% to adjust the pH of the wastewater to 6-8.

8. The method for treating wastewater from the production of the thermosensitive colorimetric reagent F-103 according to claim 1, characterized in that, In step (2), the reaction temperature for adding acidic reagents is 20-30℃ and the reaction time is 30-40min.

9. The method for treating wastewater from the production of the thermosensitive colorimetric reagent F-103 according to claim 1, characterized in that, In step (2), the acidic eluent is a hydrochloric acid solution with a mass fraction of 10-20%, and the volume ratio of the eluent to the separation phase is 1:(6-10).

10. The method for treating wastewater from the production of the thermosensitive colorimetric reagent F-103 according to claim 1, characterized in that, In step (2), the reaction temperature for adding acidic eluent to recover the separated phase is 30-50℃, and the reaction time is 20-40 min.

11. The method for treating wastewater from the production of the thermosensitive colorimetric reagent F-103 according to claim 10, characterized in that, In step (2), an acidic eluent is added to recover the separated phase. The reaction temperature is 40-45℃ and the reaction time is 25-30 min.

12. The method for treating wastewater from the production of the thermosensitive colorimetric reagent F-103 according to claim 1, characterized in that, In step (3), the adsorption temperature is 20-25℃ and the time is 25-30min.

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