Phenolic wastewater treatment method

Abstract

The invention belongs to the technical field of wastewater treatment, and particularly relates to a phenolic wastewater treatment method. According to the method disclosed by the invention, the phenolic compounds in the phenolic wastewater are primarily extracted by utilizing the coking crude diesel oil, and then the phenolic compounds in the extracted water phase are further extracted by utilizing the adsorbent, so that the reutilization of water resources is realized; coking crude diesel oil rich in phenolic compounds is gasified by directly utilizing gas heat and then is used as fuel of a gas generator, so that recycling of an oil phase is realized; the adsorbent rich in phenolic compounds can be reused after regeneration treatment. According to the invention, the 4-isopropyl styrene, the vinyl bis-triazole compound, the di (4-allyloxybenzene) sulfone and the divinylbenzene are used as functional monomers to carry out a copolymerization cross-linking reaction, and the prepared adsorbent not only has a relatively good adsorption effect on volatile phenols, but also has a relatively good adsorption effect on non-volatile phenols such as dihydric phenols and the like; the content of phenolic compounds in the coal chemical industry wastewater can be effectively reduced.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of wastewater treatment, and particularly relates to a treatment method of phenol-containing wastewater. BACKGROUND

[0002] The phenol-containing wastewater is composed of phenols, sulfides, cyanides and the like, wherein the phenols are mainly monohydric phenols, and the content of phenol is the highest, followed by meta-cresol, p-cresol, nitro-substituted phenol and polyphenol, etc., which are derived from the scrubbing water and phenol-containing condensate water in the process of cooling and purifying coal gas, and the generation amount of the phenol-containing condensate water depends on the quality of the gasified coal and the gasification process adopted.

[0003] The phenols in the phenol-containing wastewater can be divided into monohydric phenols and polyphenols, and the monohydric phenols are mostly volatile (boiling point is within 230 DEG C). The phenolic compounds are toxic to all living individuals. The phenol-containing wastewater not only brings serious threat to human health, but also harms animals and plants. Undoubtedly, the phenol-containing wastewater discharged into water bodies or used for irrigation needs to be treated so as to meet the national discharge standards.

[0004] At present, the incineration method and the steam dephenolization method are mainly used to treat the phenol-containing wastewater. The incineration method is to spray the phenol-containing wastewater into an incinerator, so that the phenolic organic matter is oxidized at a high temperature of about 1100 DEG C, and finally CO2 and H2O are discharged. This method is simple in process and convenient in operation, but has large energy consumption. Another disadvantage of the incineration method for treating the phenol-containing wastewater is that if the operation is not careful, the incomplete combustion is caused by the decrease of the furnace temperature, and secondary pollution is easily caused. The steam dephenolization method is to heat the phenol-containing wastewater, so that the phenol is volatilized with water vapor, and then the part of the phenol-containing steam is introduced into the bottom of the producer to mix with air as a gasification agent, and the phenol is burned and decomposed into CO2 and H2O at a high temperature in the furnace, so as to achieve the purpose of dephenolization. The disadvantage of the steam dephenolization method is that the energy consumption is large.

[0005] In order to reduce the energy consumption, the phenol-containing wastewater can be heat-exchanged with high-temperature coal gas, or the phenol-containing wastewater can be heated and gasified by using other waste heat and then incinerated or used as a gasification agent. However, there are some phenols which are difficult to volatilize in the phenol-containing wastewater, which causes the incomplete treatment of the phenolic pollutants, and the composition of the gasified phenol-containing wastewater is complex, which easily causes the unstable gasification process and affects the product quality when the gasified phenol-containing wastewater is used as a gasification agent. SUMMARY

[0006] In view of the above problems, the present application provides a treatment method of phenol-containing wastewater, which is used to solve the problem that the composition of the gasified phenol-containing wastewater is complex when the phenol-containing wastewater is gasified by using waste heat and then used as a gasification agent, which causes the unstable gasification process and affects the product quality.

[0007] To achieve the above object, the technical scheme adopted by the present application is as follows:

[0008] A phenol-containing wastewater treatment method, comprising the following steps: using coking crude diesel to extract the phenol-containing wastewater to preliminarily remove phenol, to obtain an oil phase and a water phase; using the oil phase as fuel after gasification by waste heat; using the water phase as gasification agent after gasification by waste heat or as steam; and using the purified water after deep phenol removal by an adsorbent, wherein the adsorbent is prepared by the following method: 4-isopropylstyrene, a vinyl-bis-triazole compound, bis(4-allyloxyphenyl) sulfone, divinylbenzene and a pore-forming agent are subjected to a polymerization reaction in an emulsion under the action of an initiator to obtain the adsorbent; and the vinyl-bis-triazole compound has the following structure:

[0009] .

[0010] Preferably, the mass ratio of the 4-isopropylstyrene, the vinyl-bis-triazole compound, the bis(4-allyloxyphenyl) sulfone and the divinylbenzene is 1.1-1.3:0.3-0.5:0.08-0.12:0.15-0.3.

[0011] Preferably, the initiator is benzoyl peroxide, the temperature of the polymerization reaction is 80-90 DEG C, and the time is 5-7 h.

[0012] Preferably, the pore-forming agent is toluene.

[0013] Preferably, the mass ratio of the 4-isopropylstyrene, the vinyl-bis-triazole compound, the bis(4-allyloxyphenyl) sulfone, the divinylbenzene, the benzoyl peroxide and the toluene is 1.1-1.3:0.3-0.5:0.08-0.12:0.15-0.3:0.03-0.05:1.2-1.5.

[0014] Preferably, the emulsion is a polyvinyl alcohol solution with a mass fraction of 3-4%.

[0015] Preferably, the polyvinyl alcohol solution is prepared by dissolving polyvinyl alcohol with an alcoholysis degree of 87-89% in water, and the polyvinyl alcohol has a molecular weight of 35000-40000.

[0016] Preferably, the mass ratio of the mixed solution and the polyvinyl alcohol solution is 1:5-7, and the mixed solution is composed of the 4-isopropylstyrene, the vinyl-bis-triazole compound, the bis(4-allyloxyphenyl) sulfone, the divinylbenzene, the pore-forming agent and the initiator.

[0017] Preferably, the volume ratio of the phenol-containing wastewater and the coking crude diesel is 1:1.8-2.

[0018] Preferably, the preparation method of the vinyl bis-triazole compound is as follows: diazotization reaction is carried out on triazole aniline, and then azidation reaction is carried out to obtain a triazole azide compound; then the triazole azide compound and 3-butyn-1-ol are mixed to obtain a bis-triazole alcohol compound; finally, bromination reaction is carried out on the bis-triazole alcohol compound, and then elimination reaction is carried out to obtain the vinyl bis-triazole compound; the chemical structure of the triazole aniline is as follows:

[0019] .

[0020] The method for treating phenol-containing wastewater has the following beneficial effects:

[0021] (1) The method uses coking crude diesel to preliminarily extract phenolic compounds in the phenol-containing wastewater, and then uses an adsorbent to further extract the phenolic compounds in the water phase after extraction, so as to realize the recycling of water resources; the coking crude diesel rich in phenolic compounds does not need to be further treated, and is directly gasified using coal gas heat to be used as fuel of a coal gas producer, so as to realize the recycling of oil phase; the adsorbent rich in phenolic compounds can be reused after regeneration treatment, and the phenolic compounds generated in the regeneration treatment can also be used as fuel.

[0022] (2) The adsorbent prepared by the copolymerization and cross-linking reaction of 4-isopropylstyrene, vinyl-bis-triazole compound, bis(4-allyloxyphenyl) sulfone and divinylbenzene has good adsorption effect on various phenolic compounds, and the adsorption capacity is greater than 11 mg / g, which not only has good adsorption effect on volatile phenol, but also has good adsorption effect on non-volatile phenol such as dihydric phenol, can effectively reduce the content of phenolic compounds in coal chemical industry wastewater, improve the water quality after treatment, and provide a good foundation for resource comprehensive utilization. Among them, 4-isopropylstyrene and vinyl-bis-triazole compound provide the basic skeleton matrix of the adsorption resin, bis(4-allyloxyphenyl) sulfone and divinylbenzene improve the cross-linking density and strength of the resin through cross-linking reaction, and help to form a porous structure. The hydrophobic branched hydrocarbon groups at the end of 4-isopropylstyrene in the adsorbent formed by the polymerization of various monomers are arranged in a dentiform manner, play a hooking and hanging role in the porous structure, and improve the affinity with the benzene ring in the phenolic compound; the 1,2,3-triazole structure and 1,2,4-triazole structure in the vinyl-bis-triazole compound unit are distributed at both ends of the benzene ring, the benzene ring can improve the affinity with the ring matrix of the phenolic compound, and the 1,2,3-triazole structure and 1,2,4-triazole structure at both ends of the benzene ring further improve the affinity and adsorption capacity of the phenolic compound by producing hydrogen bonds and other effects with the phenolic hydroxyl group; the hydrophilic sulfone group and ether bond in the bis(4-allyloxyphenyl) sulfone unit can effectively regulate the hydrophilicity and lipophilicity of the adsorbent, provide a certain hydrophilicity for the adsorbent on the basis of the overall lipophilicity of the adsorbent, further improve the affinity with the phenolic hydroxyl group, and then improve the adsorption capacity of the adsorbent for various phenolic compounds. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 The nuclear magnetic resonance spectrum of the vinyl-bis-triazole compound prepared in Example 1 of the present application. DETAILED DESCRIPTION

[0024] In order for those skilled in the art to better understand the technical solutions, the present application will be described in detail below in conjunction with examples, and the description in this part is only exemplary and explanatory, and should not have any limiting effect on the protection scope of the present application.

[0025] The pH of the phenol-containing wastewater used in the following examples and comparative examples is 8.2-8.5, and the volatile phenol content is 460-480 mg / L; the volatile phenol content of coking crude diesel oil is 350 mg / L, and the water content is 40 mg / L.

[0026] Example 1

[0027] The phenol-containing wastewater treatment method of the embodiment comprises the following steps: adding phenol-containing wastewater generated in a coal gas production process and coking crude diesel oil according to a volume ratio of 1:1.8-2 into an extraction tank for extraction, and separating to obtain oil phase and water phase. In other embodiments, a multi-stage extraction tank can also be used to perform multi-stage extraction of the phenol-containing wastewater by using the coking crude diesel oil.

[0028] An oil phase heating jacket is additionally arranged on a coal gas cyclone dust collector at the bottom of a coal gas generator, the oil phase obtained by extraction is introduced into the oil phase heating jacket on the coal gas cyclone dust collector at the bottom of the coal gas generator, when the bottom coal gas passes through the cyclone dust collector, heat exchange is performed between the jacket and the oil phase, the oil phase is heated and evaporated into gas, and the oil phase is used as fuel of the coal gas generator, thereby realizing recycling of the oil phase.

[0029] An adsorbent is used to perform adsorption treatment on the water phase obtained by extraction, so as to further remove phenolic compounds in the water phase, and obtain purified water; an water phase heating jacket is additionally arranged on a coal gas cyclone dust collector at the bottom of a coal gas generator, the purified water is introduced into the water phase heating jacket, when the bottom coal gas passes through the cyclone dust collector, heat exchange is performed between the jacket and the purified water, the purified water is heated and evaporated into gas, and the purified water is used as a gasification agent of the coal gas generator or as steam. When the adsorbent is used to perform adsorption treatment on the water phase obtained by extraction, an adsorption tower or an adsorption tank can be used. After the adsorbent adsorbs the phenolic compounds, the adsorbent can be desorbed and regenerated by vacuum treatment or heating treatment, the phenolic compounds generated by desorption can be used as fuel of the coal gas generator, thereby realizing zero emission of pollutants; and the regenerated adsorbent can be repeatedly used.

[0030] The preparation method of the adsorbent is as follows:

[0031] (1) triazole aniline and glacial acetic acid with a mass ratio of 1:8 are added into a reaction kettle, the mixture is uniformly stirred, and then the temperature is lowered to 0°C; a 30% sodium nitrite solution is added dropwise into the reaction kettle, and stirring reaction is performed for 1 h to obtain a diazonium salt solution; then a 30% sodium azide solution is added dropwise into the reaction kettle, and stirring reaction is continuously performed for 8 h; the reaction product is extracted by dichloromethane, the organic phase is reduced pressure distilled, and then column chromatography purification is performed by using petroleum ether, dichloromethane and methanol with a volume ratio of 8:3:1 to obtain a triazole azide compound; wherein the molar ratio of triazole aniline, sodium nitrite and sodium azide is 1:1.3:1.2, and the chemical structure of the triazole aniline is as follows:

[0032] .

[0033] (2) triazole azide compound, 3-butyn-1-ol, N, N, N', N', N''-pentamethyldiethylene triamine, cuprous bromide and N, N-dimethyl formamide are added into a stirring kettle, after being stirred uniformly, heated to 70℃, stirred for 5h, then distilled under reduced pressure to obtain a concentrated solution, the concentrated solution is purified by column chromatography using petroleum ether, dichloromethane and methanol with a volume ratio of 4:6:2 to obtain a ditriazole alcohol compound; wherein the molar ratio of the triazole azide compound, 3-butyn-1-ol, N, N, N', N', N''-pentamethyldiethylene triamine and cuprous bromide is 1:1.1:0.03:0.04, the mass of N, N-dimethyl formamide is 130% of the sum of the masses of the triazole azide compound, 3-butyn-1-ol, N, N, N', N', N''-pentamethyldiethylene triamine and cuprous bromide.

[0034] (3) the ditriazole alcohol compound and N, N-dimethyl formamide with a mass ratio of 1:5 are added into a reaction kettle, then nitrogen is introduced into the reaction kettle, and the temperature of the materials in the reaction kettle is adjusted to-5℃, under stirring, phosphorus tribromide is added dropwise into the reaction kettle, after the dropwise addition is completed, the temperature of the materials in the reaction kettle is adjusted to 80℃, stirred for 10h, distilled under reduced pressure to obtain a concentrated solution, the concentrated solution is purified by column chromatography using petroleum ether, dichloromethane and ethyl acetate with a volume ratio of 4:5:1 to obtain a ditriazole bromo compound; wherein the molar ratio of the ditriazole alcohol compound and phosphorus tribromide is 1:1.

[0035] (4) the ditriazole bromo compound and a 30% mass fraction potassium hydroxide ethanol solution are added into a reaction kettle, heated to 75℃, stirred for reflux reaction for 8h, cooled to room temperature, then the reaction product is extracted with dichloromethane, the organic phase obtained by extraction is distilled under reduced pressure to obtain a concentrated solution, the concentrated solution is purified by column chromatography using petroleum ether, dichloromethane and ethyl acetate with a volume ratio of 3:6:1 to obtain a vinyl ditriazole compound; wherein the molar ratio of the ditriazole bromo compound and potassium hydroxide in the potassium hydroxide ethanol solution is 1:4, the nuclear magnetic hydrogen spectrum of the vinyl ditriazole compound is as shown in Figure 1 , and the chemical structure is as shown below:

[0036] .

[0037] (5) 4-isopropylstyrene, vinylbistriazole compound, bis(4-allyloxyphenyl) sulfone, divinylbenzene, benzoyl peroxide and toluene with mass ratio of 1.1:0.3:0.08:0.15:0.03:1.2 were added into a reaction kettle and stirred uniformly to obtain a mixed solution, then a polyvinyl alcohol solution with mass fraction of 3% was added, heated to 80°C, stirred and reacted for 5h, centrifuged, the obtained solid was washed with ethanol, and dried to obtain the adsorption resin; wherein the mass ratio of the mixed solution and the polyvinyl alcohol solution was 1:5, and the polyvinyl alcohol solution was prepared by dissolving polyvinyl alcohol (molecular weight of 35000) with alcoholysis degree of 87% in water.

[0038] Example 2

[0039] The difference between the phenolic wastewater treatment method of the present example and the phenolic wastewater treatment method of example 1 is that the preparation method of the adsorbent used in the phenolic wastewater treatment method of the present example is as follows:

[0040] (1) Triazolyl aniline and glacial acetic acid with mass ratio of 1:9 were added into a reaction kettle, stirred uniformly, and then cooled to 2°C, then a sodium nitrite solution with mass fraction of 32% was added dropwise into the reaction kettle, stirred and reacted for 1.2h to obtain a diazonium salt solution, then a sodium azide solution with mass fraction of 33% was continuously added dropwise into the reaction kettle, and continuously stirred and reacted for 9h, the reaction product was extracted with dichloromethane, and the organic phase was reduced pressure distilled, then purified by column chromatography with petroleum ether, dichloromethane and methanol with volume ratio of 8:3:1 to obtain a triazolyl azide compound; wherein the molar ratio of triazolyl aniline, sodium nitrite and sodium azide was 1:1.4:1.3, and the chemical structure of triazolyl aniline is as follows:

[0041] .

[0042] (2) The triazolyl azide compound, 3-butyn-1-ol, N,N,N',N',N''-pentamethyldiethylene triamine, cuprous bromide and N,N-dimethylformamide were added into a stirring kettle, stirred uniformly, heated to 72°C, stirred and reacted for 6h, then reduced pressure distilled to obtain a concentrated solution, which was purified by column chromatography with petroleum ether, dichloromethane and methanol with volume ratio of 4:6:2 to obtain a bistriazolyl alcohol compound; wherein the molar ratio of the triazolyl azide compound, 3-butyn-1-ol, N,N,N',N',N''-pentamethyldiethylene triamine and cuprous bromide was 1:1.2:0.04:0.05, and the mass of N,N-dimethylformamide was 140% of the sum of the masses of the triazolyl azide compound, 3-butyn-1-ol, N,N,N',N',N''-pentamethyldiethylene triamine and cuprous bromide.

[0043] (3) adding a mass ratio of 1:6 of the dinitrobenzene compound and N,N-dimethylformamide into a reaction kettle, then introducing nitrogen into the reaction kettle, and adjusting the temperature of the material in the reaction kettle to -2℃, and then adding phosphorus tribromide dropwise into the reaction kettle under stirring, after the dropwise addition is completed, adjusting the temperature of the material in the reaction kettle to 83℃, and stirring for 11h, and then performing vacuum distillation to obtain a concentrated solution, and then performing column chromatography purification on the concentrated solution by using petroleum ether, dichloromethane and ethyl acetate in a volume ratio of 4:5:1 to obtain the dinitrobenzene compound; wherein the molar ratio of the dinitrobenzene compound and the phosphorus tribromide is 1:1.

[0044] (4) adding the dinitrobenzene compound and a mass fraction of 30% of potassium hydroxide ethanol solution into a reaction kettle, heating to 78℃, stirring and refluxing for 9h, cooling to room temperature, and then extracting the reaction product with dichloromethane, and then performing vacuum distillation on the obtained organic phase to obtain a concentrated solution, and then performing column chromatography purification on the concentrated solution by using petroleum ether, dichloromethane and ethyl acetate in a volume ratio of 3:6:1 to obtain the vinyl dinitrobenzene compound; wherein the molar ratio of the dinitrobenzene compound and the potassium hydroxide in the potassium hydroxide ethanol solution is 1:5, and the chemical structure of the vinyl dinitrobenzene compound is as follows:

[0045] .

[0046] (5) adding a mass ratio of 1.2:0.4:0.1:0.2:0.04:1.3 of 4-isopropylstyrene, the vinyl dinitrobenzene compound, divinylbenzene, di(4-allyloxyphenyl)sulfone, benzoyl peroxide and toluene into a reaction kettle, stirring uniformly to obtain a mixed solution, then adding a mass fraction of 3.5% of a polyvinyl alcohol solution, heating to 85℃, stirring for 6h, centrifuging, and then washing the obtained solid with ethanol, and then drying to obtain the adsorption resin; wherein the mass ratio of the mixed solution and the polyvinyl alcohol solution is 1:6, and the polyvinyl alcohol solution is prepared by dissolving polyvinyl alcohol (molecular weight of 38000) with an alcoholysis degree of 88% in water.

[0047] Example 3

[0048] The difference between the phenol-containing wastewater treatment method of the present embodiment and the phenol-containing wastewater treatment method of Example 1 is that the preparation method of the adsorbent used in the phenol-containing wastewater treatment method of the present embodiment is as follows:

[0049] (1) triazole aniline and glacial acetic acid with a mass ratio of 1:10 were added into a reaction kettle, and after being stirred uniformly, the temperature was lowered to 5℃, then a 35% sodium nitrite solution was added dropwise into the reaction kettle, and stirred for 1.5h to obtain a diazonium salt solution, then a 35% sodium azide solution was continuously added dropwise into the reaction kettle, and stirred for 10h, and the reaction product was extracted with dichloromethane, and after the organic phase was distilled under reduced pressure, column chromatography purification was performed with petroleum ether, dichloromethane and methanol with a volume ratio of 8:3:1 to obtain a triazole azide compound; wherein the molar ratio of triazole aniline, sodium nitrite and sodium azide is 1:1.5:1.4, and the chemical structure of triazole aniline is as follows:

[0050] .

[0051] (2) the triazole azide compound, 3-butyne-1-ol, N,N,N',N',N''-pentamethyldiethylene triamine, cuprous bromide and N,N-dimethylformamide were added into a stirring kettle, and after being stirred uniformly, the temperature was heated to 75℃, and stirred for 7h, and then distilled under reduced pressure to obtain a concentrated solution, and column chromatography purification was performed with petroleum ether, dichloromethane and methanol with a volume ratio of 4:6:2 to obtain a double triazole alcohol compound; wherein the molar ratio of triazole azide compound, 3-butyne-1-ol, N,N,N',N',N''-pentamethyldiethylene triamine and cuprous bromide is 1:1.2:0.05:0.06, and the mass of N,N-dimethylformamide is 150% of the sum of the masses of triazole azide compound, 3-butyne-1-ol, N,N,N',N',N''-pentamethyldiethylene triamine and cuprous bromide.

[0052] (3) the double triazole alcohol compound and N,N-dimethylformamide with a mass ratio of 1:7 were added into a reaction kettle, then nitrogen was introduced into the reaction kettle, and the temperature of the material in the reaction kettle was adjusted to 0℃, and under stirring, phosphorus tribromide was added dropwise into the reaction kettle, after the dropwise addition was completed, the temperature of the material in the reaction kettle was adjusted to 85℃, and stirred for 12h, and then distilled under reduced pressure to obtain a concentrated solution, and column chromatography purification was performed with petroleum ether, dichloromethane and ethyl acetate with a volume ratio of 4:5:1 to obtain a double triazole bromide compound; wherein the molar ratio of double triazole alcohol compound and phosphorus tribromide is 1:1.

[0053] (4) the reaction kettle is added with a double triazole bromide compound and a 30% by mass potassium hydroxide ethanol solution, heated to 80°C, stirred to reflux for 10 hours, cooled to room temperature, and then the reaction product is extracted with dichloromethane, and the organic phase obtained by extraction is distilled under reduced pressure to obtain a concentrated liquid, and the concentrated liquid is purified by column chromatography with petroleum ether, dichloromethane and ethyl acetate in a volume ratio of 3:6:1 to obtain a vinyl double triazole compound; wherein the molar ratio of the double triazole bromide compound to the potassium hydroxide in the potassium hydroxide ethanol solution is 1:4.5, and the chemical structure of the vinyl double triazole compound is as follows:

[0054] .

[0055] (5) the reaction kettle is added with 4-isopropylstyrene, a vinyl double triazole compound, bis(4-allyloxyphenyl)sulfone, divinylbenzene, benzoyl peroxide and toluene in a mass ratio of 1.3:0.5:0.12:0.3:0.05:1.5, stirred to be uniform to obtain a mixed solution, then a 4% by mass polyvinyl alcohol solution is added, heated to 90°C, stirred to react for 7 hours, centrifuged, and the solid obtained by centrifugation is washed with ethanol and dried to obtain an adsorbent resin; wherein the mass ratio of the mixed solution to the polyvinyl alcohol solution is 1:7, and the polyvinyl alcohol solution is prepared by dissolving a polyvinyl alcohol with an alcoholysis degree of 89% (molecular weight of 40000) in water.

[0056] Comparative Example 1

[0057] The difference between the phenol-containing wastewater treatment method of the present comparative example and the phenol-containing wastewater treatment method of Example 1 is only that the preparation method of the adsorbent used in the phenol-containing wastewater treatment method of the present comparative example is as follows:

[0058] The reaction kettle is added with 4-isopropylstyrene, a vinyl double triazole compound, divinylbenzene, benzoyl peroxide and toluene in a mass ratio of 1.1:0.3:0.23:0.03:1.2, stirred to be uniform to obtain a mixed solution, then a 3% by mass polyvinyl alcohol solution is added, heated to 80°C, stirred to react for 5 hours, centrifuged, and the solid obtained by centrifugation is washed with ethanol and dried to obtain an adsorbent resin; wherein the mass ratio of the mixed solution to the polyvinyl alcohol solution is 1:5, and the polyvinyl alcohol solution is prepared by dissolving a polyvinyl alcohol with an alcoholysis degree of 87% (molecular weight of 35000) in water. The vinyl double triazole compound is the vinyl double triazole compound prepared in Example 1.

[0059] Comparative Example 2

[0060] The difference between the phenol-containing wastewater treatment method of the present comparative example and the phenol-containing wastewater treatment method of Example 1 is only that the preparation method of the adsorbent used in the phenol-containing wastewater treatment method of the present comparative example is as follows:

[0061] The 4-isopropylstyrene, vinyl-bis-triazole compound, bis(4-allyloxyphenyl) sulfone, benzoyl peroxide and toluene with a mass ratio of 1.1:0.3:0.23:0.03:1.2 were added into a reaction kettle, stirred uniformly to obtain a mixed solution, then a polyvinyl alcohol solution with a mass fraction of 3% was added, heated to 80°C, stirred for 5h, centrifuged, and the obtained solid was washed with ethanol and dried to obtain an adsorbent resin; wherein the mass ratio of the mixed solution and the polyvinyl alcohol solution was 1:5, and the polyvinyl alcohol solution was prepared by dissolving polyvinyl alcohol with an alcoholysis degree of 87% (molecular weight of 35000) in water. The vinyl-bis-triazole compound was the vinyl-bis-triazole compound prepared in the example 1.

[0062] Comparative Example 3

[0063] The difference between the phenolic wastewater treatment method of the comparative example and the phenolic wastewater treatment method of the example 1 is only that the preparation method of the adsorbent used in the phenolic wastewater treatment method of the comparative example is as follows:

[0064] The 4-isopropylstyrene, vinyl-bis-triazole compound, bis(4-allyloxyphenyl) sulfone, benzoyl peroxide and toluene with a mass ratio of 1.1:0.3:0.23:0.03:1.2 were added into a reaction kettle, stirred uniformly to obtain a mixed solution, then a polyvinyl alcohol solution with a mass fraction of 3% was added, heated to 80°C, stirred for 5h, centrifuged, and the obtained solid was washed with ethanol and dried to obtain an adsorbent resin; wherein the mass ratio of the mixed solution and the polyvinyl alcohol solution was 1:5, and the polyvinyl alcohol solution was prepared by dissolving polyvinyl alcohol with an alcoholysis degree of 87% (molecular weight of 35000) in water. The vinyl-bis-triazole compound was the vinyl-bis-triazole compound prepared in the example 1.

[0065] Comparative Example 4

[0066] The difference between the phenolic wastewater treatment method of the comparative example and the phenolic wastewater treatment method of the example 1 is only that the preparation method of the adsorbent used in the phenolic wastewater treatment method of the comparative example is as follows:

[0067] The 4-isopropylstyrene, vinyl-bis-triazole compound, bis(4-allyloxyphenyl) sulfone, benzoyl peroxide and toluene with a mass ratio of 1.1:0.3:0.23:0.03:1.2 were added into a reaction kettle, stirred uniformly to obtain a mixed solution, then a polyvinyl alcohol solution with a mass fraction of 3% was added, heated to 80°C, stirred for 5h, centrifuged, and the obtained solid was washed with ethanol and dried to obtain an adsorbent resin; wherein the mass ratio of the mixed solution and the polyvinyl alcohol solution was 1:5, and the polyvinyl alcohol solution was prepared by dissolving polyvinyl alcohol with an alcoholysis degree of 87% (molecular weight of 35000) in water. The vinyl-bis-triazole compound was the vinyl-bis-triazole compound prepared in the example 1.

[0068] Comparative Example 5

[0069] The phenol-containing wastewater treatment method of the present comparative example differs from the phenol-containing wastewater treatment method of Example 1 only in that the vinylbistriazole compound is replaced with 1-ethenyl-1,2,4-triazole in step (5) of the preparation method of the adsorbent used in the phenol-containing wastewater treatment method of the present comparative example.

[0070] Comparative Example 6

[0071] The phenol-containing wastewater treatment method of the present comparative example differs from the phenol-containing wastewater treatment method of Example 1 only in that the vinylbistriazole compound is replaced with 1-ethenyl-1H-1,2,3-triazole in step (5) of the preparation method of the adsorbent used in the phenol-containing wastewater treatment method of the present comparative example.

[0072] Comparative Example 7

[0073] The phenol-containing wastewater treatment method of the present comparative example differs from the phenol-containing wastewater treatment method of Example 1 only in that the vinylbistriazole compound is replaced with N-ethenyl-1,2,3-triazole in step (5) of the preparation method of the adsorbent used in the phenol-containing wastewater treatment method of the present comparative example, and the structure of N-ethenyl-1,2,3-triazole is as follows:

[0074] .

[0075] Comparative Example 8

[0076] The phenol-containing wastewater treatment method of the present comparative example differs from the phenol-containing wastewater treatment method of Example 1 only in that the 4-isopropylstyrene is replaced with styrene in step (5) of the preparation method of the adsorbent used in the phenol-containing wastewater treatment method of the present comparative example.

[0077] Effect Example

[0078] In order to evaluate the treatment effect of the phenol-containing wastewater treatment method of each example and comparative example, the adsorbent in the phenol-containing wastewater treatment method of each example and comparative example was added to a conical flask, and then a standard solution of different phenolic compounds was added, and stirred until the concentration of the phenolic compounds in the solution did not change. According to the mass of the adsorbent added and the content of the phenolic compounds in the solution before and after the adsorption treatment, the saturated adsorption amount of the unit mass of the adsorbent to the phenolic compounds was calculated, and the saturated adsorption capacity of the adsorbent to different phenolic compounds was obtained, and the experimental results are shown in Table 2.

[0079] Table 2 Saturated adsorption capacity of the adsorbent in the phenol-containing wastewater treatment method of each example and comparative example (mg / g) to different phenolic compounds

[0080] in Table 2

[0081] Adsorbent Phenol o-Chlorophenol o-Nitrophenol 3,4-Dimethylphenol O-Dihydroxybenzene 4-Fluoro-1,2-dihydroxybenzene Example 1 124.53 37.41 31.58 55.76 14.29 12.83 Example 2 122.87 38.16 32.11 54.99 13.88 11.57 Example 3 125.24 37.92 31.84 55.24 14.15 12.43 Comparative Example 1 37.41 5.73 6.17 8.17 1.21 0.95 Comparative Example 2 33.06 4.17 5.42 7.11 0.95 0.81 Comparative Example 3 35.23 5.20 6.14 8.24 1.37 0.98 Comparative Example 4 34.88 4.86 5.91 7.63 1.24 1.17 Comparative Example 5 41.27 5.51 6.08 7.94 1.45 0.91 Comparative Example 6 36.19 4.97 6.23 8.03 1.33 1.02 Comparative Example 7 40.35 5.24 6.16 7.82 1.39 0.94 Comparative Example 8 38.64 4.80 5.66 7.09 1.17 0.85

[0082] As shown in Table 1, the adsorbent used in the application has good adsorption effect on various phenolic compounds, and the adsorption capacity is greater than 11 mg / g. It has good adsorption effect not only on volatile phenol but also on non-volatile phenol such as dihydric phenol. It can effectively reduce the content of phenolic compounds in coal chemical wastewater and improve the quality of treated water, providing a good foundation for resource comprehensive utilization.

[0083] As shown in Example 1 and Comparative Examples 1-4, various monomers used in the preparation of the adsorbent contribute to the adsorption of phenolic compounds. Among them, 4-isopropylstyrene and vinyl-bis-triazole compound provide the basic skeleton matrix for the adsorption resin. Bis(4-allyloxyphenyl) sulfone and divinylbenzene improve the crosslinking density and strength of the resin through crosslinking reaction, and also help to form a porous structure. In the adsorbent formed by the polymerization of various monomers, the hydrophobic branched hydrocarbon groups at the end of 4-isopropylstyrene are arranged in a dentiform manner, which plays a hooking and hanging role in the porous structure and improves the affinity with the benzene ring in the phenolic compound. The 1,2,3-triazole structure and 1,2,4-triazole structure in the vinyl-bis-triazole compound unit are distributed at both ends of the benzene ring, which can improve the affinity with the ring matrix of phenolic compounds. The 1,2,3-triazole structure and 1,2,4-triazole structure at both ends of the benzene ring further improve the affinity and adsorption capacity of the adsorbent for phenolic compounds by forming hydrogen bonds with the phenolic hydroxyl group. The hydrophilic sulfone group and ether bond in the bis(4-allyloxyphenyl) sulfone unit can effectively regulate the hydrophilic and lipophilic properties of the adsorbent. On the basis of the overall lipophilicity of the adsorbent, it provides a certain hydrophilicity to the adsorbent, further improves the affinity with the phenolic hydroxyl group, and thus improves the adsorption capacity of the adsorbent for various phenolic compounds. Therefore, the adsorbent prepared by the cooperation of various monomers has high adsorption capacity for various phenolic compounds.

[0084] As shown in Example 1 and Comparative Examples 5-7, although higher triazole content monomers are used to prepare the adsorbent in Comparative Examples 5-7, the triazole content in the prepared adsorbent is higher, but the triazole in Comparative Examples 5-6 is far away from the benzene ring in the adsorbent, which cannot form the tandem structure in Example 1, resulting in limited action of triazole and low adsorption capacity. In Comparative Example 7, the benzene ring has only one side with triazole structure, which has limited improvement in the affinity for phenolic compounds. This experiment again proves that the triazole-benzene ring-triazole in the vinyl-bis-triazole compound unit is beneficial to the efficient adsorption of phenolic compounds.

[0085] As shown in Example 1 and Comparative Example 8, after replacing 4-isopropylstyrene with styrene, a large number of hydrophobic branched hydrocarbon groups arranged in a dentiform manner are lacking in the porous structure of the adsorbent, which reduces the affinity of the adsorbent for phenolic compounds and reduces the adsorption capacity.

[0086] It should be noted that, in the present text, the terms comprising, including and any other variant are intended to encompass the non-exclusive inclusion, so that a process, method, article or device that includes a series of elements not only includes those elements, but also includes other elements not explicitly listed or inherent to such a process, method, article or device. The principles and embodiments of the present application are described herein using specific examples. The above examples are only used to help understand the method of the present application and its core idea. The above is only the preferred embodiment of the present application. It should be noted that due to the limitation of language expression, there are infinite specific structures objectively. For ordinary skilled persons in the art, without departing from the principles of the present application, some improvements, refinements or changes can be made, or the above technical features can be combined in an appropriate manner; these improvements, refinements, changes or combinations, or the direct application of the concepts and technical solutions of the present application to other occasions without improvement, shall be regarded as the protection scope of the present application.

Claims

1. A method for treating phenolic wastewater, characterized by, It comprises the following steps: The phenol-containing wastewater is extracted by coking crude diesel oil to preliminarily remove phenol, and oil phase and water phase are obtained; the oil phase is gasified by using waste heat and used as fuel, the water phase is deeply dephenolated by using an adsorbent, and purified water is obtained, the purified water is gasified by using waste heat and used as a gasification agent or steam, and the adsorbent is prepared by the following method: 4-isopropylstyrene, vinyl-bis-triazole compound, bis(4-allyloxyphenyl) sulfone, divinylbenzene and pore-forming agent are subjected to polymerization reaction in an emulsion under the action of an initiator to obtain the adsorbent; the vinyl-bis-triazole compound has the following structure: 。 2. The method for treating phenol-containing wastewater according to claim 1, characterized by, The mass ratio of the 4-isopropylstyrene, vinyl-bis-triazole compound, bis(4-allyloxyphenyl) sulfone and divinylbenzene is 1.1-1.3:0.3-0.5:0.08-0.12:0.15-0.

3.

3. The method of treating phenolic wastewater according to claim 1 or 2, characterized in that, The initiator is benzoyl peroxide, the temperature of the polymerization reaction is 80-90 DEG C, and the time is 5-7 h.

4. The method for treating phenol-containing wastewater according to claim 3, characterized by, The pore-forming agent is toluene.

5. The method of treating phenolic wastewater according to claim 4, wherein The mass ratio of the 4-isopropylstyrene, vinyl-bis-triazole compound, bis(4-allyloxyphenyl) sulfone, divinylbenzene, benzoyl peroxide and toluene is 1.1-1.3:0.3-0.5:0.08-0.12:0.15-0.3:0.03-0.05:1.2-1.

5.

6. The phenol-containing wastewater treatment method according to claim 1 or 2, characterized by, The emulsion is a polyvinyl alcohol solution with a mass fraction of 3-4%.

7. The method of treating phenolic wastewater according to claim 6, wherein The polyvinyl alcohol solution is prepared by dissolving polyvinyl alcohol with an alcoholysis degree of 87-89% in water, and the molecular weight of the polyvinyl alcohol is 35000-40000.

8. The method of treating phenolic wastewater according to claim 6, wherein The mass ratio of the mixed solution and the polyvinyl alcohol solution is 1:5-7, and the mixed solution is composed of 4-isopropylstyrene, vinyl-bis-triazole compound, bis(4-allyloxyphenyl) sulfone, divinylbenzene, pore-forming agent and initiator.

9. The method of treating phenolic wastewater according to claim 1, wherein The volume ratio of the phenol-containing wastewater and coking crude diesel oil is 1:1.8-2.

10. The method of treating phenolic wastewater of claim 1, wherein, The preparation method of the vinyl-bis-triazole compound is as follows: triazole aniline is subjected to diazotization reaction and then azido reaction to obtain a triazole azide compound; then the triazole azide compound and 3-butyn-1-ol are subjected to mixing reaction to obtain a bis-triazole alcohol compound; finally, the bis-triazole alcohol compound is subjected to bromination reaction and then elimination reaction to obtain the vinyl-bis-triazole compound; the chemical structure of the triazole aniline is as follows: 。

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