A method for preparing and using an organic extractant for organic compounds in wastewater

Abstract

A method for preparing and using an organic matter extractant in wastewater, comprising: 1) reacting hypoxanthine I with phosphorus oxychloride to obtain a chloro product II, then condensing the chloro product II with 5-(2-acetyloxyethyl)tetrahydrofuran-2,3,4-triyl triacetate to obtain compound III, and then subjecting the compound III to ammonolysis to obtain compound IV; 2) adding glycerol distearate and phosphorus oxychloride to a mixed solution of tetrahydrofuran and triethylamine to react to generate a phosphoryl chloride intermediate V; 3) hydrolyzing and acidifying the compound IV and the intermediate V in a mixed solution of tetrahydrofuran and triethylamine to obtain an extractant adenosine phosphate glycerol distearate VI; and 4) mechanically mixing the extractant adenosine phosphate glycerol distearate VI and aviation kerosene to obtain an organic matter extractant product in wastewater. The organic matter extractant in wastewater of the present application mainly uses adenosine phosphate ester compounds and related derivatives as a main extractant, extracts and separates various organic matters in wastewater, has a high removal rate of organic matters, and has a high recovery rate of the extractant.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of organic wastewater treatment; in particular, it relates to a preparation method and use method of an organic matter extractant in wastewater. BACKGROUND

[0002] The pollutants in high-concentration organic industrial wastewater are complex and toxic, and are difficult to treat. It is difficult to directly enter the biochemical treatment system, and must be pretreated to reduce the concentration of pollutants and improve the biodegradability of the wastewater. Common pretreatment methods include advanced oxidation, incineration, adsorption and extraction. However, due to the high concentration of pollutants, advanced oxidation requires a large amount of energy and harsh reaction conditions, high equipment investment and operating cost; incineration requires a large amount of fuel gas, and the tail gas after incineration needs to be treated, which is high in investment and operating cost for large-volume industrial wastewater; oxidation and incineration destroy organic matter with energy, which is a serious waste of resources for recyclable organic matter. The adsorption method can quickly adsorb water pollutants, but the adsorption material has a short adsorption period and is difficult to regenerate after saturation, and finally the adsorption material needs to be disposed as hazardous waste; the extraction method uses an extractant to combine with water pollutants to separate the pollutants from water, and the extractant can be regenerated and the pollutants can be recovered through back extraction, which is simple and fast, and low in energy consumption.

[0003] In the industrial wastewater extraction process, common extractants include diisopropyl ether, methyl isobutyl ketone, and tributyl phosphate. Although they have a certain extraction effect on water pollutants, they have a large solubility in water, and need to be recovered by distillation, resulting in a high loss rate of the extractant and high recovery cost.

[0004] Patent 202011624498.0 discloses an extractant mainly composed of methyl isobutyl ketone, and compounded with C6-C9 saturated aliphatic ketones and / or C7-C9 saturated aliphatic alcohols, which has an extraction efficiency of more than 97.4% for unit phenol and polyphenol in wastewater, but the problem of high water solubility of the main extractant methyl isobutyl ketone is not solved. Patent 201410741135.3 discloses an extractant compounded with kerosene as a diluent, supplemented with an acid extractant and an amine extractant for coal dry distillation wastewater dephenolization, wherein the acid extractant is one or both of diisooctyl phosphate and 2-ethylhexyl phosphonic acid di(2-ethylhexyl) ester; the amine extractant is one or both of dodecylamine and tridecylamine. The acid extractant is dissolved in alkali and cannot be regenerated with alkali, but its boiling point is relatively high, and the energy consumption for distillation recovery of the extractant is high. Patent 201911338099.5 discloses an extractant compounded with fentanyl and naphtha, but the extractant has the problems of high water solubility and high volatility, resulting in a high loss rate.

[0005] Although the above-mentioned extractant has a good extraction rate for volatile phenol in water, in addition to phenolic substances in wastewater, most of the straight-chain hydrocarbon substances also have a high content, which can also make the COD value of the wastewater high, and inhibit the subsequent biochemical treatment system. Therefore, developing an extractant which has good extraction efficiency for phenolic and straight-chain hydrocarbon substances has important significance for the pretreatment of high-concentration organic wastewater. SUMMARY

[0006] The present application aims to overcome the shortcomings of the prior art, and provides a preparation method and use method of an organic matter extractant in wastewater. Adenosine phosphate compounds and their related derivatives are used as extractants to remove phenolic, benzene ring and straight-chain small molecule organic matter through hydrogen bonding and similar compatibility principles; the solvent property of the extractant in water is reduced by the long-chain ester group, the recovery rate of the extractant is improved, and the wastewater treatment cost is further reduced.

[0007] To achieve the above-mentioned purpose, the following technical solutions are adopted in the present application:

[0008] A preparation method of an organic matter extractant in wastewater, comprising the following method steps:

[0009] 1) taking hypoxanthine I as a raw material, reacting with phosphorus oxychloride to obtain a chloro product II, then condensing with 5-(2-acetyloxyethyl)tetrahydrofuran-2,3,4-triyl triacetate to obtain compound III, and then subjecting to ammonia methanol mixed solution and ammonolysis to obtain compound IV;

[0010] 2) adding glyceryl tristearate and phosphorus oxychloride to a mixed solution of tetrahydrofuran and triethylamine to react to generate a phosphoryl chloride intermediate V;

[0011] 3) hydrolyzing and acidifying the compound IV obtained in step 1) and the intermediate V obtained in step 2) in a mixed solution of tetrahydrofuran and triethylamine to obtain the extractant adenosine phosphate glyceryl tristearate VI;

[0012] 4) mechanically mixing the extractant adenosine phosphate glyceryl tristearate VI and aviation kerosene to obtain the required organic matter extractant product in wastewater.

[0013] In the organic matter extractant product in wastewater, the volume percentage content of the extractant adenosine phosphate glyceryl tristearate VI is 20% to 40%, and the volume percentage content of the aviation kerosene is 60% to 80%.

[0014] The synthesis steps of the extractant are carried out at normal temperature and pressure, which is simple and convenient to operate.

[0015] The method for using the extractant prepared by the preparation method of the organic matter extractant in waste water is that the waste water containing organic matter and the extractant are countercurrently and sequentially fed into multiple centrifugal extractors, the mixing and separation of the extractant and the waste water are completed in the centrifugal process, and the removal of the organic matter in the waste water is realized.

[0016] The number of the centrifugal extractors is 1-5, and the volume ratio of the extractant to the waste water is 1:(1-8).

[0017] The used extractant is stripped by a NaOH solution with a mass concentration of 6-10%, the NaOH solution and the used extractant are countercurrently and sequentially fed into multiple centrifugal stripping extractors, the regeneration of the extractant is completed in the centrifugal process, and the recycling of the extractant is realized.

[0018] The number of the centrifugal stripping extractors is 1-4, and the volume ratio of the NaOH solution to the used extractant is 1:(3-6).

[0019] Compared with the prior art, the method has the beneficial effects that:

[0020] The organic matter extractant in waste water provided by the application mainly uses adenosine phosphate compounds and related derivatives as the main extractant, extracts and separates various organic matters in waste water, greatly improves the removal rate of organic matter, and reduces the subsequent biochemical process load; the long-chain ester group in the extractant reduces the solubility of the extractant in water, and improves the recovery rate of the extractant. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 is a schematic diagram of the principle of the extraction of the extractant on the organic matter containing hydroxyl groups.

[0022] Figure 2 is a synthesis schematic diagram of adenosine triacetate (IV).

[0023] Figure 3 is a synthesis schematic diagram of the phosphorus oxychloride intermediate (V).

[0024] Figure 4 is a synthesis schematic diagram of adenosine phosphate distearate glyceride (VI).

[0025] Figure 5 is the analysis spectrum diagram of the raw water of semi-coke in Example 1.

[0026] Figure 5 Middle: 1, phenol 2, 2-methylphenol 3, p-methylphenol 4, pyrrolidine-2, 5-dione 5, 4-ethylphenol 6, 3, 5-dimethylphenol 7, 3, 4-dimethylphenol 8, 2-ethyl-4-methylphenol 9, 5-indenol 10, 1-naphthol.

[0027] Figure 6 is the analysis spectrum diagram of the extracted water in Example 1.

[0028] Figure 6 M: 1, aniline 2, 2, 6, 10-trimethyltetradecane 3, adenosine phosphate distearate glyceride 4, tetracosane. DETAILED DESCRIPTION

[0029] The present application will be described in detail below by way of examples, but the practice of the present application is not limited to the following examples.

[0030] As shown in the figure, a method for preparing an organic matter extractant in wastewater comprises the following method steps: Figures 1-4

[0031] 1) Using hypoxanthine I as a raw material, reacting with phosphorus oxychloride to obtain a chloro product II, then condensing with 5-(2-acetyloxyethyl)tetrahydrofuran-2,3,4-triyl triacetate to obtain compound III, and then ammonolysis with an ammonia-methanol mixed solution to obtain compound IV;

[0032] 2) Adding glycerol distearate and phosphorus oxychloride to a mixed solution of tetrahydrofuran and triethylamine to react to form a phosphorus oxychloride intermediate V;

[0033] 3) Hydrolyzing and acidifying compound IV obtained in step 1) and intermediate V obtained in step 2) in a mixed solution of tetrahydrofuran and triethylamine to obtain the extractant adenosine phosphate distearate glyceride VI;

[0034] 4) Mechanically mixing the extractant adenosine phosphate distearate glyceride VI and aviation kerosene to obtain the required organic matter extractant product in wastewater.

[0035] In the organic matter extractant product in wastewater, the volume percentage content of the extractant adenosine phosphate distearate glyceride VI is 20% to 40%, and the volume percentage content of the aviation kerosene is 60% to 80%. All operations are carried out at normal temperature and pressure.

[0036] The use method and implementation effect of the present application will be illustrated by examples below.

[0037] In the organic matter extractant product in wastewater, the volume percentage content of the extractant adenosine phosphate distearate glyceride VI is 30%, and the volume percentage content of the aviation kerosene is 70%.

[0038] ​The volatile phenol content in the wastewater of a certain coal is 4182 mg / L, the COD is 31640 mg / L, the pH value of the wastewater is 5.32, the ratio of the wastewater to the extractant is 4:1, and the wastewater enters three centrifugal extractors to realize the extraction separation of the organic matters in the wastewater through three-stage extraction. The phenol-containing extraction phase and the NaOH solution with a mass concentration of 6% enter three centrifugal back-extractors to realize the regeneration of the extractant, and the recovery rate of the extractant is 99.85%. The volatile phenol content in the effluent after extraction is 106 mg / L, and the removal rate is 97.5%. The COD of the effluent is 2646 mg / L, and the removal rate is 91.6%.

[0039] By Figure 5 And Figure 6 It can be seen that the number and types of pollutants in the effluent after extraction are greatly reduced, indicating that the extractant has obvious removal effect on phenols, benzene rings and straight-chain small-molecule organic matters in water.

[0040] In the extractant product for the extraction of organic matters in wastewater, the volume percentage of the extractant adenosine phosphate distearate glyceride VI is 25%, and the volume percentage of aviation kerosene is 75%.

[0041] The volatile phenol content in the wastewater of a certain coal is 4711 mg / L, the COD is 38564 mg / L, the pH value of the wastewater is 6.98, the ratio of the wastewater to the extractant is 3:1, and the wastewater enters three centrifugal extractors to realize the extraction separation of the organic matters in the wastewater through three-stage extraction. The phenol-containing extraction phase and the NaOH solution with a mass concentration of 8% enter three centrifugal back-extractors to realize the regeneration of the extractant, and the recovery rate of the extractant is 99.88%. The volatile phenol content in the effluent after extraction is 110 mg / L, and the removal rate is 97.7%. The COD of the effluent is 3587 mg / L, and the removal rate is 90.7%.

[0042] In the extractant product for the extraction of organic matters in wastewater, the volume percentage of the extractant adenosine phosphate distearate glyceride VI is 40%, and the volume percentage of aviation kerosene is 60%.

[0043] The volatile phenol content in the wastewater of a certain coal is 4711 mg / L, the COD is 38564 mg / L, the pH value of the wastewater is 6.98, the ratio of the wastewater to the extractant is 3:1, and the wastewater enters three centrifugal extractors to realize the extraction separation of the organic matters in the wastewater through three-stage extraction. The phenol-containing extraction phase and the NaOH solution with a mass concentration of 8% enter three centrifugal back-extractors to realize the regeneration of the extractant, and the recovery rate of the extractant is 99.88%. The volatile phenol content in the effluent after extraction is 110 mg / L, and the removal rate is 97.7%. The COD of the effluent is 3587 mg / L, and the removal rate is 90.7%.

[0044] Example 4: In the organic matter extraction agent product in wastewater, the volume percentage of the extraction agent adenosine phosphoric acid distearate VI is 20%, and the volume percentage of aviation kerosene is 80%.

[0045] After regeneration and recovery of the extraction agent, the volatile phenol content in the coking waste water is 3968 mg / L, the COD is 26480 mg / L, the pH value of the waste water is 5.5, the ratio of waste water to extraction agent is 5:1, and the waste water enters three centrifugal extractors, and after three-stage extraction, the organic matter in the waste water is extracted and separated. The phenol-containing extraction phase and the 6% NaOH solution are mixed at a ratio of 5:1, and the mixture enters three centrifugal stripping machines to regenerate the extraction agent, and the recovery rate of the extraction agent is 99.84%. After extraction, the volatile phenol content in the effluent is 115 mg / L, and the removal rate is 97.1%; the COD of the effluent is 2389 mg / L, and the removal rate is 90.9%. The recovery rate of the extraction agent and the removal rate of the pollutants remain good, indicating that the low loss rate and high pollutant removal rate of the extraction agent have good stability.

[0046] The above only describes the preferred embodiments of the present application, and it should be noted that for those skilled in the art, without departing from the concept of the present application, several improvements and refinements can be made, and these improvements and refinements should also be considered within the protection scope of the present application.

Claims

1. A method for preparing an organic extractant for use in wastewater, characterized by, The method comprises the following steps: 1) using hypoxanthine I as raw material, reacting with phosphorus oxychloride to obtain chloro product II, then condensing with 5-(2-acetoxyethyl) tetrahydrofuran-2,3,4-triyl triacetate to obtain compound III, and then ammonolysis with ammonia-methanol mixed solution to obtain compound IV; 2) adding glycerol distearate and phosphorus oxychloride into a mixed solution of tetrahydrofuran and triethylamine to generate phosphorus oxychloride intermediate V; 3) hydrolyzing and acidifying compound IV obtained in step 1) and intermediate V obtained in step 2) in a mixed solution of tetrahydrofuran and triethylamine to obtain extractant adenosine phosphate glycerol distearate VI; 4) mechanically mixing extractant adenosine phosphate glycerol distearate VI and aviation kerosene to obtain the required wastewater organic matter extractant product.

2. The method for preparing an organic extractant from wastewater according to claim 1, characterized in that, In the wastewater organic matter extractant product, the volume percentage of extractant adenosine phosphate glycerol distearate VI is 20% to 40%, and the volume percentage of aviation kerosene is 60% to 80%.

3. A method of using the extractant prepared by the method of claim 1, characterized in that, The organic matter-containing wastewater and the extractant are countercurrently introduced into multiple centrifugal extractors in sequence, and the mixing and separation of the extractant and the wastewater are completed in the centrifugal process, so that the removal of the organic matter in the wastewater is realized.

4. A method of using the extractant prepared by the method of claim 3, characterized in that, The number of the centrifugal extractors is 1 to 5, and the volume ratio of the extractant to the wastewater is 1: (1 to 8).

5. A method of using the extractant prepared by the method of claim 4, characterized in that, The used extractant is back-extracted with NaOH solution with a mass concentration of 6% to 10%, and the NaOH solution and the used extractant are countercurrently introduced into multiple centrifugal back-extractors in sequence, and the regeneration of the extractant is completed in the centrifugal process, so that the recycling of the extractant is realized.

6. A method of using the extractant prepared by the method of claim 5, characterized in that, The number of the centrifugal back-extractors is 1 to 4, and the volume ratio of the NaOH solution to the used extractant is 1: (3 to 6).

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