An extractant for simetryn wastewater treatment and a treatment method thereof

Abstract

The present application belongs to the technical field of metribuzin wastewater treatment, and particularly relates to an extractant for metribuzin wastewater treatment and a treatment method thereof. The metribuzin wastewater treatment method comprises the following steps: preparing a metribuzin wastewater extractant; uniformly dispersing the metribuzin wastewater extractant into acidic wastewater, continuously stirring, extracting impurities in the acidic wastewater by the metribuzin wastewater extractant, standing and separating after the extraction is completed, and collecting the water phase and the oil phase after the separation; and recycling sulfuric acid in the water phase by a high-temperature concentration process to obtain high-concentration sulfuric acid, wherein the water produced by the concentration process does not need to be discharged and can be continuously used. The present application removes impurities in metribuzin wastewater by preparing an extractant, purifies acidic wastewater, recycles water, sulfuric acid, methanol and the extractant by a high-temperature concentration and negative pressure distillation process, realizes resource recycling and utilization, improves production efficiency, reduces cost, and reduces environmental burden.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of metribuzin wastewater treatment, and particularly relates to an extractant for metribuzin wastewater treatment and a treatment method thereof. BACKGROUND

[0002] Metribuzin is a widely used selective systemic herbicide, which exerts herbicidal action by inhibiting photosynthesis of sensitive plants. Its chemical name is 4-amino-6-tert-butyl-4, 5-dihydro-3-methylthio-1, 2, 4-triazine-5 (4H) -one, the molecular formula is C7H 14 N4OS, the molecular weight is 214.29, the CAS number is 21087-64-9, and the structure is as follows:

[0003]

[0004] In the prior art, common synthesis methods of metribuzin include alkali catalysis and acid catalysis. In the alkali catalysis method, a methylation reagent such as bromomethane or chloromethane is used to methylate the mercapto group of triazinone in the presence of an inorganic base in a methanol solution to obtain the product. In the acid catalysis method, a methylation reagent such as dimethyl sulfate or monomethyl sulfate is used to methylate the mercapto group of triazinone in the presence of sulfuric acid in a methanol solution. The reaction equations of the two methods are as follows:

[0005]

[0006] The alkali catalysis method has low conversion rate and high cost. In the process of producing metribuzin by the acid catalysis method, amine, alcohol and ketone-containing acidic wastewater is inevitably generated due to the need of the production process. The treatment of this wastewater is difficult, which not only increases the production cost but also causes certain burden to the environment, thereby causing great difficulty in the treatment and discharge of the acidic wastewater. For example, a method for treating wastewater generated in the methylation reaction in the synthesis of metribuzin is disclosed in CN101445304, which can only treat the methylation wastewater in the production of metribuzin, and the treatment process is long and has high energy consumption. For another example, a pretreatment method for metribuzin pesticide production wastewater is disclosed in CN102173525B, which recycles toxic organic matters such as triazinone, methanol and metribuzin in the wastewater by ink separation, rectification and complex extraction, but the amine impurities, alcohol impurities and ketone impurities in the wastewater cannot be removed.

[0007] Based on the above problems, the present application provides an extractant for metribuzin wastewater treatment and a treatment method thereof, which aims to effectively solve the treatment problem of the amine, alcohol and ketone-containing acidic wastewater generated in the production process of metribuzin, and simultaneously reduce the production cost and the burden on the environment. SUMMARY

[0008] The present application aims to provide a kind of simetryn wastewater treatment with extractant and its treatment method, by preparing extractant to remove impurities in simetryn wastewater, purify acidic wastewater, using high-temperature concentration and negative pressure distillation process to recover water, sulfuric acid, methanol and extractant, realize resource recycling and utilization, improve production efficiency, reduce cost, reduce environmental burden.The technology efficiently and stably treats simetryn wastewater, with significant environmental and economic benefits.

[0009] The technical solutions adopted by the present application are as follows:

[0010] A kind of simetryn wastewater treatment method, comprising the following steps:

[0011] Step 1: preparing simetryn wastewater extractant;

[0012] Step 2: uniformly disperse simetryn wastewater extractant into acidic wastewater, continuously stir, extract impurities in acidic wastewater by simetryn wastewater extractant, after extraction, stratify and collect water phase and oil phase after stratification;

[0013] Step 3: recover sulfuric acid in water phase by high-temperature concentration process, obtain high-concentration sulfuric acid, the water produced by concentration process does not need to be discharged, continue to be used;

[0014] Step 4: treat oil phase by negative pressure distillation process, wherein, recover methanol by forefraction, recover simetryn wastewater extractant by midfraction and continue to be used in impurity extraction section, and residual still residue is subjected to biochemical treatment.

[0015] In a preferred scheme, in step 2, the amount of simetryn wastewater extractant is 5% to 10% of the volume of the treated wastewater.

[0016] In a preferred scheme, in step 2, the stirring speed is 100 to 150 rpm, and the stirring time is 30 to 60 min.

[0017] In a preferred scheme, in step 3, the content of recovered high-concentration sulfuric acid is 90% to 95%, and the obtained high-concentration sulfuric acid is used in the product simetryn synthesis section.

[0018] In a preferred scheme, in step 3, the temperature of high-temperature concentration process is 115 to 120℃.

[0019] A kind of high-efficiency extractant, suitable for any one of the simetryn wastewater treatment methods described above, comprising the following components by volume fraction: amine extractant 1 to 3 parts, ketone extractant 1 to 2 parts, alcohol extractant 1 to 3 parts, diluent 4 to 6 parts;

[0020] The amine extractant is one or more of the following: tri-n-octylamine, tri-n-decylamine, N,N-dioctyldecylamine, the ketone extractant is one or more of the following: acetone, methoxyacetone, n-decyl n-decanoate, the alcohol extractant is one or more of the following: fatty alcohol mixture C16-C20, 2-propyl-1-heptanol, and the diluent is one or more of the following: C8-C9 solvent oil, C10-C13 solvent oil, xylene.

[0021] In a preferred embodiment, the extractant for oxaziclomefone wastewater comprises the following components by volume fraction: tri-n-decylamine 1 part, methoxyacetone 2 parts, 2 parts of fatty alcohol mixture C16-C20, C8-C9 solvent oil 5 parts.

[0022] In a preferred embodiment, the extractant for oxaziclomefone wastewater comprises the following components by volume fraction: N,N-dioctyldecylamine 1 part, acetone 1 part, 2-propyl-1-heptanol 3 parts, C8-C9 solvent oil 5 parts.

[0023] In a preferred embodiment, the extractant for oxaziclomefone wastewater comprises the following components by volume fraction: tri-n-octylamine 1 part, n-decyl n-decanoate 2 parts, 2-propyl-1-heptanol 1 part, xylene 6 parts.

[0024] In a preferred embodiment, the extractant for oxaziclomefone wastewater comprises the following components by volume fraction: tri-n-octylamine 1 part, n-decyl n-decanoate 3 parts, 2-propyl-1-heptanol 2 parts, C10-C13 solvent oil 4 parts.

[0025] The present application has the following technical effects:

[0026] The present application removes three typical types of organic impurities in oxaziclomefone wastewater by preparing an oxaziclomefone wastewater extractant, purifies the acidic wastewater, and then respectively recovers water, sulfuric acid and methanol in the acidic wastewater and the extractant by high-temperature concentration process and negative pressure distillation process, so as to realize full recovery and utilization of resources, greatly improve production efficiency, reduce raw material cost, make up for the defects of the prior art that multiple impurities need to be removed in steps, reduce production cost and environmental burden, realize efficient and stable treatment of oxaziclomefone wastewater, and have obvious environmental and economic benefits. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 is a flowchart of the treatment of oxaziclomefone wastewater according to the present application;

[0028] Figure 2 is a graph showing the content of impurities in EA-extracted wastewater before treatment of the oxaziclomefone wastewater extractant according to the present application;

[0029] Figure 3is the impurity content chart in the -EA extracted wastewater after the oxaziclomefone wastewater extractant treatment of the present application. DETAILED DESCRIPTION

[0030] In order to make the above objectives, features and advantages of the present application more apparent, the specific embodiments of the present application are described in detail below with reference to the accompanying drawings.

[0031] In the following description, a lot of specific details are set forth in order to provide a thorough understanding of the present application, but the present application can also be practiced in other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the concept of the present application, so the present application is not limited to the specific embodiments disclosed below.

[0032] Secondly, the "one embodiment" or "embodiment" referred to herein means that the specific features, structures or characteristics can be included in at least one implementation of the present application. "In a preferred embodiment" appearing in different places in the specification does not mean the same embodiment, nor is it an embodiment that is separate or alternative to other embodiments.

[0033] The present application provides an extractant for oxaziclomefone wastewater treatment, comprising the following components by volume fraction: 1-3 parts of amine extractant, 1-2 parts of ketone extractant, 1-3 parts of alcohol extractant, 4-6 parts of diluent;

[0034] Among them, the amine extractant is one or more of the following substances: tri-n-octylamine, tri-n-decylamine, N,N-dioctyl decylamine, the ketone extractant is one or more of the following substances: acetone, methoxy acetone, n-decyl n-decanoate, the alcohol extractant is one or more of the following substances: fatty alcohol mixture C16-C20, 2-propyl-1-heptanol, and the diluent is one or more of the following substances: C8-C9 solvent oil, C10-C13 solvent oil, xylene.

[0035] Here, in the production process of oxaziclomefone, three typical impurities of amine, ketone and alcohol will be produced, and these three types of impurities will remain in the acidic wastewater during post-processing, which is a very big difficulty for subsequent wastewater treatment and discharge. In this embodiment, the extractant formula is prepared by amine extractant, ketone extractant, alcohol extractant and diluent, which can efficiently remove three typical organic impurities in oxaziclomefone wastewater, purify the acidic wastewater, and realize efficient and stable treatment of the difficult biodegradable oxaziclomefone wastewater.

[0036] Example 1

[0037] An extractant for oxaziclomefone wastewater treatment, comprising the following components by volume fraction: 1 part of tri-n-decylamine, 2 parts of methoxy acetone, 2 parts of fatty alcohol mixture C16-C20, and 5 parts of C8-C9 solvent oil.

[0038] Referring to Figure 1 As shown in the figure, a method for treating metribuzin wastewater is as follows: 1 part of tri-n-decylamine, 2 parts of methoxyacetone, 2 parts of a fatty alcohol mixture C16-C20, and 5 parts of C8-C9 solvent oil are put into a stirring device, stirred at a speed of 150 rpm for 30 minutes, to obtain a metribuzin wastewater extractant, the metribuzin wastewater extractant is added to metribuzin wastewater, the stirring speed is controlled to be 150 rpm, and after stirring extraction for 30 minutes, the mixture is allowed to stand and separate into layers, and the water phase and the oil phase are collected respectively, the impurity removal rate is 99.2%, the oil phase is treated by a negative pressure distillation process, the forefraction and the midfraction are collected, and the postfraction and the residue containing impurities are subjected to biochemical treatment, wherein methanol is recovered through the forefraction, the metribuzin wastewater extractant is recovered through the midfraction and is continuously used in the impurity extraction section; the water phase is subjected to high-temperature concentration process to recover sulfuric acid, the concentration process temperature is set to be 120℃, the heating is stopped when the sulfuric acid content reaches 90%, the sulfuric acid recovery rate is 92%, and the concentrated high-concentration sulfuric acid is recovered and used in the product metribuzin synthesis section.

[0039] It should be noted that in this embodiment, the metribuzin wastewater extractant is 10% of the wastewater treatment amount by volume.

[0040] Example Two

[0041] A metribuzin wastewater treatment extractant includes the following components by volume fraction: 1 part of N,N-dioctyldecylamine, 1 part of acetone, 3 parts of 2-propyl-1-heptanol, and 5 parts of C8-C9 solvent oil.

[0042] A method for treating metribuzin wastewater is as follows: 1 part of N,N-dioctyldecylamine, 1 part of acetone, 3 parts of 2-propyl-1-heptanol, and 5 parts of C8-C9 solvent oil are put into a stirring device, stirred at a speed of 150 rpm for 30 minutes, to obtain a metribuzin wastewater extractant, the metribuzin wastewater extractant is added to metribuzin wastewater, the stirring speed is controlled to be 150 rpm, and after stirring extraction for 30 minutes, the mixture is allowed to stand and separate into layers, and the water phase and the oil phase are collected respectively, the impurity removal rate is 99.2%, the oil phase is treated by a negative pressure distillation process, the forefraction and the midfraction are collected, and the postfraction and the residue containing impurities are subjected to biochemical treatment, wherein methanol is recovered through the forefraction, the metribuzin wastewater extractant is recovered through the midfraction and is continuously used in the impurity extraction section; the water phase is subjected to high-temperature concentration process to recover sulfuric acid, the concentration process temperature is set to be 120℃, the heating is stopped when the sulfuric acid content reaches 90%, the sulfuric acid recovery rate is 92%, and the concentrated high-concentration sulfuric acid is recovered and used in the product metribuzin synthesis section.

[0043] It should be noted that in this embodiment, the metribuzin wastewater extractant is 10% of the wastewater treatment amount by volume.

[0044] Example Three

[0045] An extractant for treating metribuzin wastewater, comprising the following components by volume fraction: tri-n-octylamine 1 part, n-decanoic acid n-decyl ester 2 parts, 2-propyl-1-heptanol 1 part, dimethylbenzene 6 parts.

[0046] A method for treating metribuzin wastewater is as follows: 1 part of tri-n-decylamine, 2 parts of n-decanoic acid n-decyl ester, 2 parts of 2-propyl-1-heptanol, and 6 parts of dimethylbenzene are put into a stirring device, stirred at a speed of 150 rpm for 30 minutes to obtain a metribuzin wastewater extractant, the metribuzin wastewater extractant is added to metribuzin wastewater, the stirring speed is controlled at 150 rpm, and after stirring extraction for 30 minutes, it is left to separate into water phase and oil phase, the impurity removal rate is 99.5%, the oil phase is treated by a negative pressure distillation process, the front and middle distillates are collected, and the rear distillate and the residue containing impurities are subjected to biochemical treatment, wherein methanol is recovered by the front distillation, the metribuzin wastewater extractant is recovered by the middle distillation and is continuously used in the impurity extraction section; the water phase is subjected to high-temperature concentration process to recover sulfuric acid, the concentration process temperature is set to 120℃, the heating is stopped when the sulfuric acid content reaches 90%, the sulfuric acid recovery rate is 92%, and the concentrated high-concentration sulfuric acid is recovered and used in the product metribuzin synthesis section.

[0047] It should be noted that in this embodiment, the metribuzin wastewater extractant is 8% of the volume of the wastewater to be treated.

[0048] Example Four

[0049] An extractant for treating metribuzin wastewater, comprising the following components by volume fraction: tri-n-octylamine 1 part, n-decanoic acid n-decyl ester 3 parts, 2-propyl-1-heptanol 2 parts, C10-C13 solvent oil 4 parts.

[0050] A method for treating metribuzin wastewater is as follows: 1 part of tri-n-decylamine, 3 parts of n-decanoic acid n-decyl ester, 2 parts of 2-propyl-1-heptanol, and 4 parts of C10-C13 solvent oil are put into a stirring device, stirred at a speed of 150 rpm for 30 minutes to obtain a metribuzin wastewater extractant, the metribuzin wastewater extractant is added to metribuzin wastewater, the stirring speed is controlled at 150 rpm, and after stirring extraction for 30 minutes, it is left to separate into water phase and oil phase, the impurity removal rate is 99.0%, the oil phase is treated by a negative pressure distillation process, the front and middle distillates are collected, and the rear distillate and the residue containing impurities are subjected to biochemical treatment, wherein methanol is recovered by the front distillation, the metribuzin wastewater extractant is recovered by the middle distillation and is continuously used in the impurity extraction section; the water phase is subjected to high-temperature concentration process to recover sulfuric acid, the concentration process temperature is set to 120℃, the heating is stopped when the sulfuric acid content reaches 92%, the sulfuric acid recovery rate is 96%, and the concentrated high-concentration sulfuric acid is recovered and used in the product metribuzin synthesis section.

[0051] It should be noted that in this embodiment, the metribuzin wastewater extractant is 5% of the volume of the wastewater to be treated.

[0052] In summary, in Embodiment One to Embodiment Four, the components of the extractant for treating metribuzin wastewater are as shown in the following table:

[0053]

[0054] Test Example One

[0055] Take 200 grams of metribuzin wastewater, add 15 grams of ethyl acetate to extract the impurities therein, and use chromatography to detect the impurity content. The detection results are shown in Table 1. Figure 2

[0056] Test Example Two

[0057] In which, the metribuzin wastewater extractant prepared in Embodiment One to Embodiment Four is used to extract the impurities in the metribuzin wastewater, and then 15 grams of ethyl acetate is added to extract the impurities therein. The impurity content is detected by chromatography. The detection results are shown in the following table:

[0058]

[0059] It should be noted that in Test Example One and Test Example Two, the equipment used to detect the impurities in the metribuzin wastewater after extraction is a Fuli GC-9790 II FID detector with a detector temperature of 250°C. Of course, other detection equipment can be used for detection according to the actual environment, which does not constitute a specific limitation.

[0060] In which, the detection results of the metribuzin wastewater extractant prepared in Embodiment Three for extracting the impurities in the metribuzin wastewater are shown in Table 2, combined with Table 1, Figure 3 Figure 2 Figure 3 and the metribuzin wastewater treatment process table, Figure 1 In Table 2, the peak at 1.495 min is the ethyl acetate peak; the peaks at 3.49 min and 5.0 min are alcohol impurity peaks; the peaks at 8.143 min and 12.58 min are ketone impurity peaks; the peaks at 8.853 min and 18.95 are amine impurity peaks; Figure 2 In Table 2, the peak at 1.488 min is the ethyl acetate peak; the peaks at 8.853 min and 9.99 are amine impurity peaks (the slight shift in peak time is a normal phenomenon); by Figure 1 and Figure 2 ​​​​Comparing the impurity content in wastewater, it can be seen that after treatment with the extractant formula, at 3.49 min, 5.0 min, 8.143 min and 12.58 min, the alcohol and ketone impurity peaks are completely removed, and only a small amount of amine impurities remain, fully reflecting the impurity removal effect after using the extractant formula. The content of alcohol impurities, ketone impurities and amine impurities in wastewater is significantly reduced. In summary, the oxaziclomefone wastewater extractant prepared by Examples 1 to 4 all showed significant effects in removing impurities in wastewater, with impurity removal rates of more than 98%. In these examples, the extractant prepared in Example 3 showed particularly outstanding impurity removal effect when treating oxaziclomefone wastewater, with the highest removal rate. At the same time, in Example 4, although the prepared extractant was not the highest in impurity removal rate, it achieved the highest sulfuric acid recovery rate during the treatment process. Although the oxaziclomefone wastewater extractants prepared in Examples 1 to 4 had slight differences in treatment effect, they all had good impurity removal rate and sulfuric acid recovery rate, realizing the resource utilization of wastewater. The acid wastewater treated by the extractant formula can effectively recover the sulfuric acid therein. The recovered sulfuric acid can be used back in the oxaziclomefone synthesis section, greatly improving production efficiency and reducing raw material cost, making up for the defect in the prior art that multiple impurities need to be removed step by step, and having certain innovative significance and good industrialization promotion value. At the same time, it reduces production cost and environmental burden, realizes efficient and stable treatment of oxaziclomefone wastewater, and has obvious environmental and economic benefits.

[0061] The above only describes the preferred embodiments of the present application. It should be noted that for those skilled in the art, without departing from the principles of the present application, several improvements and refinements can be made, which should also be considered within the scope of protection of the present application. Structures, devices and operation methods not specifically described and explained in the present application, if not specifically described and limited, are implemented according to conventional means in the art.

Claims

1. A method for treating oxaziclomefone wastewater, characterized by: The method comprises the following steps: Step 1: preparing the metribuzin wastewater extractant; Step 2: uniformly dispersing the metribuzin wastewater extractant into the acidic wastewater, continuously stirring, extracting the impurities in the acidic wastewater by the metribuzin wastewater extractant, and collecting the water phase and the oil phase after the extraction is completed and the layers are separated; Step 3: recovering sulfuric acid in the water phase by a high-temperature concentration process to obtain high-concentration sulfuric acid, and the water produced by the concentration process does not need to be discharged and can be continuously used; Step 4: treating the oil phase by a negative pressure distillation process, wherein methanol is recovered by the front distillation, the metribuzin wastewater extractant is recovered by the middle distillation and is continuously used in the impurity extraction section, and the remaining still residue is subjected to biochemical treatment. The metribuzin wastewater extractant comprises the following components by volume fraction: 1-3 parts of an amine extractant, 1-2 parts of a ketone extractant, 1-3 parts of an alcohol extractant, and 4-6 parts of a diluent. The amine extractant is one or more of the following: tri-n-octylamine, tri-n-decylamine, and N,N-dioctyldecylamine; the ketone extractant is one or more of the following: acetone, methoxyacetone, and n-decanoyl n-decyl ester; the alcohol extractant is one or more of the following: a fatty alcohol mixture C16-C20 and 2-propyl-1-heptanol; and the diluent is one or more of the following: C8-C9 solvent oil, C10-C13 solvent oil, and xylene.

2. The method for treating metribuzin wastewater according to claim 1, characterized in that: In step 2, the amount of the metribuzin wastewater extractant is 5%-10% of the amount of the wastewater to be treated.

3. The method for treating metribuzin wastewater according to claim 1, characterized in that: In step 2, the stirring speed is 100-150 rpm, and the stirring time is 30-60 min.

4. The method for treating metribuzin wastewater according to claim 1, characterized in that: In step 3, the content of the recovered high-concentration sulfuric acid is 90%-95%, and the obtained high-concentration sulfuric acid is used in the metribuzin synthesis section.

5. The method for treating metribuzin wastewater according to claim 1, characterized in that: In step 3, the temperature of the high-temperature concentration process ranges from 115 to 120°C.

6. The method for processing metribuzin wastewater according to claim 1, characterized in that: The metribuzin wastewater extractant comprises the following components by volume fraction: 1 part of tri-n-decylamine, 2 parts of methoxyacetone, 2 parts of a fatty alcohol mixture C16-C20, and 5 parts of C8-C9 solvent oil.

7. The method for processing metribuzin wastewater according to claim 1, characterized in that: The metribuzin wastewater extractant comprises the following components by volume fraction: 1 part of N,N-dioctyldecylamine, 1 part of acetone, 3 parts of 2-propyl-1-heptanol, and 5 parts of C8-C9 solvent oil.

8. The method for treating metribuzin wastewater according to claim 1, characterized in that: The metribuzin wastewater extractant comprises the following components by volume fraction: 1 part of tri-n-octylamine, 2 parts of n-decanoyl n-decyl ester, 1 part of 2-propyl-1-heptanol, and 6 parts of xylene.

9. The method for treating metribuzin wastewater according to claim 1, characterized in that: The metribuzin wastewater extractant comprises the following components by volume fraction: 1 part of tri-n-octylamine, 3 parts of n-decanoyl n-decyl ester, 2 parts of 2-propyl-1-heptanol, and 4 parts of C10-C13 solvent oil.

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