CN103979631A - Adsorption-catalytic oxidation degrading method for phenol in waste water - Google Patents
Adsorption-catalytic oxidation degrading method for phenol in waste water Download PDFInfo
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- CN103979631A CN103979631A CN201410228423.9A CN201410228423A CN103979631A CN 103979631 A CN103979631 A CN 103979631A CN 201410228423 A CN201410228423 A CN 201410228423A CN 103979631 A CN103979631 A CN 103979631A
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- phenol
- waste water
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Abstract
The invention relates to an adsorption-catalytic oxidation degrading method for phenol in waste water, and belongs to the technical field of water treatment. The method is characterized in that active carbon fibers which are loaded with ferroferric oxide are used as an adsorption agent and filled in an adsorption tower so as to adsorb the waste water containing phenol; hydrogen peroxide aqueous solution is added into the adsorption tower, air is also blown into the adsorption tower, and the mixed system is oxidized for 1h to 3h, so that the adsorption agent is regenerated, and then the waste water containing phenol is inputted to be circularly adsorbed. By adopting the method, the desorption regeneration problem of the active carbon fibers after adsorbing phenol, the degradation problem of the desorbed phenol and the high energy consumption problem of the catalytic wet-type hydrogen peroxide oxidation technology in treating the waste water containing a great amount of phenol can be solved. The method has the advantages of simple process, easiness in operation, no secondary pollution on the environment and the like.
Description
Technical field
The invention belongs to water-treatment technology field, be specifically related to absorption and the catalytic oxidation treatment technology of phenolic wastewater.
Background technology
Phenolic wastewater extensively derives from the industries such as petrochemical complex, synthon, medicine, is that a class toxicity is high and be difficult to biodegradable organic waste water, and traditional biochemical process exists long, the shortcoming such as processing efficiency is low for the treatment of time, is difficult to meet the demand that enterprise produces.In the treatment process of phenolic wastewater, the existing a large amount of reports of the treatment processs such as absorption, heterogeneous catalytic oxidation.Absorption method is to utilize the porous character absorption Pollutants in Wastewater of sorbent material, and as a kind of traditional wastewater processing technology, it can remove multiple pollutant in waste water effectively, and after processing, effluent quality is good and more stable.Sorbent material generally has larger specific surface area and stronger adsorptive power, and common sorbent material has gac, activated carbon fiber, resin, molecular sieve etc.The advantages such as for the absorption of phenol in wastewater, activated carbon fiber is a kind of sorbent material of excellent property, has treatment condition gentleness, and adsorption rate is fast, loading capacity is large, activated carbon fiber can be reused after desorption and regeneration.Application number is to adopt the method for current flow heats to regenerate to activated carbon fiber in the technology of CN02133116.2, (the activated carbon fiber Refinery Wastewater prospect such as Xu Zhida, Treatment of Industrial Water 1998,18 (2)) adopt 200 DEG C～500 DEG C superheated vapours to carry out desorption and regeneration to activated carbon fiber, there is the shortcoming that energy consumption is higher in aforesaid method, and solvent desorption method can be introduced new chemical substance, therefore the regeneration of activated carbon fiber is the subject matter of its application of puzzlement.In addition, the organic pollutant after desorption still needs to process.
Adopt the existing a large amount of reports of research of the heterogeneous catalytic oxidation method Phenol-Containing Wastewater Treatment such as photochemical catalysis, O3 catalytic oxidation, catalytic wet atmospheric oxidation, catalytic wet hydrogen peroxide oxidation, wherein catalytic wet hydrogen peroxide oxidation process employing hydrogen peroxide is oxygenant, there is the features such as equipment is simple, operational condition is gentle, non-secondary pollution, but in lot of documents report this method, the optimum activity temperature of catalyzer is many more than 50 DEG C, process above if whole waste water of factory are all heated to 50 DEG C, energy consumption is also the subject matter that affects its application again.As can be seen here, single treatment process is difficult to realize effective degraded of phenol in wastewater, and the advantage of multiple methods that need to be coupled is processed the phenol in waste water.Patent (application number 200710015182.X) adopts phenolic compound in active carbon fiber-ozone Synergistic degradation water, has obtained good phenol clearance, but in patent, has not mentioned the COD clearance of phenolic wastewater.Application number is in CN201210142480.6, to disclose a kind ofly to mix cerium nano titanium oxide/activated carbon fiber composite photo-catalyst and preparation method thereof for purifying air, improved the photocatalytic activity of nano titanium oxide, but light-catalysed efficiency is also not high in wastewater treatment.
Summary of the invention
In order to solve the desorption and regeneration problem after carbon fiber adsorption and catalytic combustion phenol, the object of the invention is to propose the method for phenol in a kind of absorption-catalyzed oxidation technology degrading waste water.
Technical solution of the present invention is: taking the activated carbon fiber of load Z 250 as sorbent material and fill in adsorption tower, waste water containing phenol is carried out after adsorption treatment, aqueous hydrogen peroxide solution is added in adsorption tower, and blast air simultaneously, mixed system carried out oxide treatment after 1～3 hour, sorbent material is regenerated, then input is containing the waste water circulation adsorption treatment of phenol.
Principle of work of the present invention:
(1) at the upper load Z 250 (Fe of viscose-based active carbon fiber (ACF)
3o
4), by load the activated carbon fiber (Fe of Z 250
3o
4/ ACF) layering fills in adsorption tower, for adsorbing the phenol of waste water.This waste water is that early stage is through pretreated waste water such as sedimentations.
(2) after Adsorption of Phenol is saturated, add appropriate aqueous hydrogen peroxide solution, and blast air simultaneously, utilize the Fe of load in activated carbon fiber
3o
4for catalyzer, hydrogen peroxide and air are oxygenant, and the result of oxidizing reaction is: be carbonic acid gas, water by the phenol degrading being adsorbed in activated carbon fiber, activated carbon fiber is regenerated.In operation, air has also played the effect that bubbling stirs.
(3) in the present invention, with the Fe of load in activated carbon fiber
3o
4during for catalyzer, hydrogen peroxide and air have synergistic oxidation effect, and during separately taking hydrogen peroxide as oxygenant or separately taking air as oxygenant, phenol degrading effect is all undesirable, and hydrogen peroxide and air add the rate of oxidation that has greatly improved phenol simultaneously.
The present invention is first adsorbed the phenol in industrial pretreated waste water by the sorbent material of metal active constituent modification, by phenol rich to sorbent material, add again oxygenant Pyrogentisinic Acid to carry out catalyzing oxidizing degrading taking the metal active constituent on sorbent material as catalyzer, desorbing agent is regenerated.Owing to degrading again after phenol rich, not only bring into play the effective advantage of catalytic wet hydrogen peroxide oxidation, do not need all waste water intensification oxide treatment yet.Therefore, the present invention solves the desorption and regeneration problem after carbon fiber adsorption and catalytic combustion phenol, has solved the degradation problem of phenol after desorption, also solves catalytic wet hydrogen peroxide oxidation technology higher problem of energy consumption in the time processing a large amount of phenolic wastewater.The present invention has that technique is simple, processing ease, environment be there is no to the advantages such as secondary pollution.
In addition, the empty tower gas velocity scope that the present invention blasts air is 0.02～0.06m/s, ensures that air can be through adsorbent bed, can ensure again the stable of bed.So-called empty tower gas velocity refers to that the flow of air is divided by the cross-sectional area of adsorption tower.
H in the aqueous hydrogen peroxide solution that the present invention adds
2o
2with the mol ratio of the phenol adsorbing on sorbent material be 14～28: 1, ensure in theory the hydrogen peroxide consumption that oxidation of phenol is required.
When oxide treatment, the temperature of mixed system is 30 DEG C～70 DEG C, preferably 50 DEG C～60 DEG C, and Fe in this temperature range
3o
4better catalytic activity be conducive to the oxidation of phenol.
Brief description of the drawings
Fig. 1 is Fe
3o
4scanning electron microscope picture.
Fig. 2 is the scanning electron microscope picture of ACF.
Fig. 3 is Fe
3o
4the scanning electron microscope picture of/ACF.
Fig. 4 is the structural representation of absorption-catalyzing oxidizing degrading device.
Fig. 5 is the liquid chromatogram of waste water before absorption.
Fig. 6 is the liquid chromatogram of waste water after absorption.
Embodiment
One, the activated carbon fiber (Fe of load Z 250
3o
4/ ACF) preparation:
1. activated carbon fiber (ACF): (specific surface area is greater than 1100m to adopt the viscose-based active carbon fiber felt of selling on market
2/ g).Fig. 1 is shown in by its scanning electron microscope picture.
2. Fe
3o
4preparation:
Get respectively 6.0 g FeCl
36H
2o, 3.0 g polyvinylpyrrolidones (PVP) and 6.0 g anhydrous Na Ac, then add 120 mL ethylene glycol, at room temperature stir 2.0 h, guarantee that all solids material is all dissolved in ethylene glycol.Above-mentioned mixed solution is transferred in the stainless steel cauldron of inner liner polytetrafluoroethylene, said mixture is reacted to 6.0h at 200 DEG C.After reaction finishes, naturally cool to room temperature, with distilled water wash repeatedly, dry 24 h of 60 DEG C, vacuum.
The Fe of preparation
3o
4scanning electron microscope picture see Fig. 2.
3. Fe
3o
4the preparation of/ACF:
Other condition was with 2, and difference is that mixed solution is transferred to after the stainless steel cauldron of inner liner polytetrafluoroethylene, adds 3.0gACF in mixed solution, 200 DEG C of reactions 6 hours.After reaction finishes, naturally cool to room temperature, activated carbon fiber in reactor taken out, with distilled water wash repeatedly, 60 DEG C of dry 24 h of vacuum, make Fe
3o
4/ ACF, wherein Fe
3o
4content is 3.2%(w%).
Other condition is identical, adds the ACF of Different Weight in mixed solution, can obtain respectively Fe
3o
4activated carbon fiber (the Fe of the load Z 250 of content (being charge capacity)
3o
4/ ACF).
The Fe obtaining
3o
4fig. 3 is shown in by the scanning electron microscope picture of/ACF.
Two, contain the absorption-catalytic oxidation cycle method of the waste water of phenol:
As shown in Figure 4, be assembled into absorption-catalytic oxidizing equipment.
Operation instructions:
(1) by Fe
3o
4/ ACF segmentation fills in adsorption tower;
(2), while absorption, shut-off valve 2,3,4,5,6, opens valve 1,7;
(3) start waste water pump, carry out adsorption operations;
(4) after absorption finishes, shut-off valve 1,7, opens valve 2,3,4,5, input aqueous hydrogen peroxide solution, and after conveying finishes, shut-off valve 3,4,5;
(5) open valve 6, process after certain hour, shut-off valve 6, opens valve 7.
When processing, waste water has liquid spraying device in tower top ingress, and there is distribution device in gas-fluid air ingress at the bottom of tower, and there is heating jacket control oxidizing temperature in adsorption column outside.
Concrete operations example: get 3.0g Fe
3o
4/ ACF, wherein Fe
3o
4content is 3.2%(w%), divide three sections and fill in the glass device that internal diameter is 2cm.Certain industrial phenolic wastewater phenol concentration is 102.0mg/L, and COD is 786.0mg/L, and waste water is sent into absorption-oxidation unit by peristaltic pump, wastewater flow 30mL/min.Carry after 1.8L waste water, reach adsorption equilibrium, water outlet COD is 138.0mg/L, and in water outlet, phenol content is 3.8mg/L, calculates thus to obtain the equilibrium adsorption capacity q of ACF
e=58.9 (mg/g).Be adsorbed liquid after treatment and discharge in time adsorption unit by leakage fluid dram.
The liquid chromatography of adsorbing forward and backward waste water is shown in shown in Fig. 5,6, and comparison diagram 5,6 is visible: through Fe
3o
4after/ACF absorption, in liquid, phenol content reduces greatly, and visible phenol in wastewater is adsorbed on Fe
3o
4on/ACF.
After absorption finishes, by the sealing of fluid inlet and leakage fluid dram, then to the H that inputs 40mL in glass device
2o
2the aqueous solution [H
2o
2/ phenol (mol ratio)=28:1], controlling the empty tower gas velocity of air is 0.03m/s, and the temperature of controlling mixed system is 50 DEG C and carries out oxide treatment, and the treatment time is about 3.0h.After testing, reach 100.0% through the simultaneous oxidation phenol desorption rate of hydrogen peroxide and air, after oxidation, in water outlet, phenol do not detected.
After oxidation, obtain the sorbent material adsorption treatment for the waste water containing phenol capable of circulation of regeneration.
Contrast scheme: after absorption finishes, other condition is constant, as added hydrogen peroxide separately in glass device, after oxidation, phenol desorption rate is 27.0%; As separately, to input air in glass device, after oxidation, phenol desorption rate is 15.3%.Can adopt hydrogen peroxide and air to be oxidized, the raising of Pyrogentisinic Acid's desorption rate has significant effect simultaneously.
The measuring method of phenol desorption rate: be adsorbed onto Fe before oxide treatment
3o
4phenol quality on/ACF (is designated as m
1); By the Fe carrying out after oxide treatment
3o
4/ ACF takes out, and with 10% quantitative NaOH eluant solution, the quality of measuring phenol in elutriant (is designated as m
2).
Desorption rate=.
By changing H
2o
2temperature, the oxidization time of mixed system when empty tower gas velocity with the mol ratio of adsorbing phenol on sorbent material, air by adsorption column, oxidation, record respectively after the desorption rate of phenol and oxidation the content of phenol in water outlet, the results are shown in following table.
Claims (5)
1. absorption-catalyzing oxidizing degrading method of a phenol in wastewater, it is characterized in that activated carbon fiber taking load Z 250 as sorbent material and fill in adsorption tower, waste water containing phenol is carried out after adsorption treatment, aqueous hydrogen peroxide solution is added in adsorption tower, and blast air simultaneously, mixed system carried out oxide treatment after 1～3 hour, and sorbent material is regenerated, the adsorption treatment by the sorbent circulation of regeneration for the waste water containing phenol.
2. degradation method according to claim 1, the empty tower gas velocity that it is characterized in that blasting air is 0.02～0.06m/s.
3. degradation method according to claim 1, the H in the aqueous hydrogen peroxide solution that it is characterized in that adding
2o
2with the mol ratio of the phenol adsorbing on sorbent material be 14～28: 1.
4. degradation method according to claim 1, while it is characterized in that oxide treatment, the temperature of mixed system is 30～70 DEG C.
5. degradation method according to claim 4, while it is characterized in that oxide treatment, the temperature of mixed system is 50～60 DEG C.
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Cited By (11)
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|---|---|---|---|---|
| CN105347561A (en) * | 2015-11-26 | 2016-02-24 | 常州大学 | Integrated device for purifying phenol-containing geothermal water |
| CN105800723A (en) * | 2016-05-09 | 2016-07-27 | 东华大学 | Hardly-degradable organic wastewater treatment method and device |
| CN105905972A (en) * | 2016-05-09 | 2016-08-31 | 东华大学 | High-efficiency reducing treatment method and device for degradation-resistant organic substances in industrial wastewater |
| CN105903460A (en) * | 2016-05-09 | 2016-08-31 | 东华大学 | Powdered activated carbon ectopic self generation and regeneration method for hard-degradation organic wastewater treatment |
| CN106492785A (en) * | 2016-08-31 | 2017-03-15 | 浙江奇彩环境科技股份有限公司 | A kind of catalyst and its method of wastewater treatment for dye wastewater treatment |
| CN107398277A (en) * | 2016-10-24 | 2017-11-28 | 西南石油大学 | Application of the cupro-nickel molten iron talcs catalyst in wastewater containing phenol of degrading |
| CN107570213A (en) * | 2017-10-12 | 2018-01-12 | 湖北工业大学 | A kind of preparation method of ferroso-ferric oxide paper substrate heterogeneous catalysis material |
| CN108218146A (en) * | 2018-03-19 | 2018-06-29 | 苏州依斯倍环保装备科技有限公司 | A kind for the treatment of process and processing system of rubber chemicals class high concentrated organic wastewater |
| CN111320318A (en) * | 2020-03-19 | 2020-06-23 | 烟台金正环保科技有限公司 | Zero-emission advanced treatment process for RO (reverse osmosis) concentrated water |
| CN113209970A (en) * | 2021-05-13 | 2021-08-06 | 哈尔滨工业大学 | Preparation method and application of carbon-based catalyst prepared from excess sludge |
| CN114853199A (en) * | 2021-02-03 | 2022-08-05 | 中国石油化工股份有限公司 | System and method for treating wastewater containing benzopyrene |
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Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105347561A (en) * | 2015-11-26 | 2016-02-24 | 常州大学 | Integrated device for purifying phenol-containing geothermal water |
| CN105800723A (en) * | 2016-05-09 | 2016-07-27 | 东华大学 | Hardly-degradable organic wastewater treatment method and device |
| CN105905972A (en) * | 2016-05-09 | 2016-08-31 | 东华大学 | High-efficiency reducing treatment method and device for degradation-resistant organic substances in industrial wastewater |
| CN105903460A (en) * | 2016-05-09 | 2016-08-31 | 东华大学 | Powdered activated carbon ectopic self generation and regeneration method for hard-degradation organic wastewater treatment |
| CN106492785A (en) * | 2016-08-31 | 2017-03-15 | 浙江奇彩环境科技股份有限公司 | A kind of catalyst and its method of wastewater treatment for dye wastewater treatment |
| CN107398277A (en) * | 2016-10-24 | 2017-11-28 | 西南石油大学 | Application of the cupro-nickel molten iron talcs catalyst in wastewater containing phenol of degrading |
| CN107570213A (en) * | 2017-10-12 | 2018-01-12 | 湖北工业大学 | A kind of preparation method of ferroso-ferric oxide paper substrate heterogeneous catalysis material |
| CN108218146A (en) * | 2018-03-19 | 2018-06-29 | 苏州依斯倍环保装备科技有限公司 | A kind for the treatment of process and processing system of rubber chemicals class high concentrated organic wastewater |
| CN111320318A (en) * | 2020-03-19 | 2020-06-23 | 烟台金正环保科技有限公司 | Zero-emission advanced treatment process for RO (reverse osmosis) concentrated water |
| CN114853199A (en) * | 2021-02-03 | 2022-08-05 | 中国石油化工股份有限公司 | System and method for treating wastewater containing benzopyrene |
| CN114853199B (en) * | 2021-02-03 | 2023-10-13 | 中国石油化工股份有限公司 | Treatment system and method for benzopyrene-containing wastewater |
| CN113209970A (en) * | 2021-05-13 | 2021-08-06 | 哈尔滨工业大学 | Preparation method and application of carbon-based catalyst prepared from excess sludge |
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