A method for treating organic amine degradation products by catalysis

Abstract

The application belongs to the technical field of wastewater treatment, and discloses a method for treating organic amine degradation products by catalysis. In view of the degradation products of amine absorbents in the process of decarburization, coordination chemical bonds are loaded on composite materials to solidify transition metals, the composite materials are made into porous polymers, and the porous polymers provide the contact area between the organic amine degradation products and the photocatalytic reaction to improve the reaction efficiency. The organic amine degradation products after the photocatalytic oxidation reaction are further oxidized and degraded to reduce the COD in the organic amine degradation products. According to the content of the COD, the number of cycles can be determined to improve the removal rate of the COD, and the content of the COD in the organic amine degradation products cannot be detected, and the purpose of complete mineralization is achieved.

Description

TECHNICAL FIELD

[0001] The present application relates to a method for treating organic amine degradation products by catalysis, and belongs to the technical field of wastewater treatment. BACKGROUND

[0002] The climate change caused by the excessive emission of CO2 has become a global environmental problem that plagues human survival and development, and reducing CO2 emission has become a common topic for all countries in the world. The absorption method using amine as the absorbent has the advantages of fast gas absorption rate, good removal effect and good chemical stability, and becomes the most feasible method for carbon capture.

[0003] The amine absorbent is oxidized and degraded during the decarburization process, and the degradation products include formic acid, formamide vinyl alcohol, acetaldehyde, glycine, glycolic acid, hydroxyacetaldehyde, oxazolidinone, oxamide, N-(2-hydroxyethyl)-acetamide (HEA), dimethyl ethanolamine (DMEA), etc. The organic amine compounds in the degradation products are difficult to be biologically degraded, have certain toxicity to microorganisms and cannot enter the sewage treatment plant, and the traditional wastewater treatment methods include physical method, chemical method and biological method.

[0004] The treatment process of industrial wastewater generally combines the first-order physical and chemical treatment (such as filtration, chemical coagulation and sedimentation method) with the second-order biological treatment (such as activated sludge method) to be able to treat the wastewater to the discharge standard. However, with the development of industry and the wide use of special chemicals, the products, by-products or derived waste in the industrial production process have inhibitory or toxic effects on organisms, or contain high concentrations of difficult-to-degrade organic or inorganic pollutants, so that the traditional sewage treatment device is difficult to handle.

[0005] Recently, due to the rapid rise of the carbon capture industry, the wastewater generated has great changes in water quality, and the traditional wastewater treatment process is basically difficult to handle, and other high economic cost treatment processes need to be used.

[0006] The photocatalytic oxidation method is a new type of water pollution treatment technology, which uses a semiconductor catalyst (such as TiO2) to generate hydroxyl radicals with strong oxidation ability in water to oxidize the pollutants in water, so that they are eventually generated into CO2, H2O and other inorganic ions. The semiconductor catalyst is easy to lose and not easy to recover when added to the sewage. The ozone direct oxidation treatment technology has a certain effect on the degradation of the desulfurization amine-containing wastewater, but the oxidation time is long. SUMMARY

[0007] The purpose of the present application is to solve the problems of low treatment efficiency and incomplete mineralization of organic pollutants in the existing organic amine degradation product wastewater, and a method for treating organic amine degradation products by catalysis is proposed to realize the harmless treatment technology of organic amine degradation product wastewater.

[0008] The main technical scheme of the present application is a method for treating organic amine degradation products by catalysis, characterized in that a porous composite material loaded photolysis catalyst is used to decompose the organic amine degradation products, and the decomposed degradation products are subjected to catalytic oxidation decomposition of organic pollutants by ozone, and the COD is removed by continuous treatment.

[0009] Generally, the method of the present application comprises a photocatalytic reactor and a catalytic oxidation reactor, the organic amine degradation products enter the photocatalytic reactor from a circulating tank, the organic amine degradation products are decomposed under the action of the photolysis catalyst, the decomposed degradation products enter the catalytic oxidation reactor, and the organic pollutants are decomposed by catalytic oxidation of ozone, and the COD removal rate is improved by continuous treatment.

[0010] The photolysis catalyst is iridate or niobate.

[0011] The porous composite material is a porous polymer of polyvinyl or divinylbenzene, and the specific surface area of the porous polymer is 100-600 m 2 / m 3 , and preferably 300-550 m 2 / m 3 .

[0012] The photocatalytic reactor is provided with photolysis irradiation light, and the wavelength range of the irradiation light is 300-400 nm.

[0013] The photolysis irradiation light uses a mercury lamp with a power of 10-500 W, and preferably a power of 100-400 W.

[0014] The catalytic oxidation reactor is provided with a liquid inlet, an ozone injection inlet and a waste gas outlet.

[0015] A circulating pump and a flow regulating valve are provided between the circulating tank, the photocatalytic reactor and the catalytic oxidation reactor.

[0016] The method of the present application further comprises centrifugal pumps, control valves and other components which are well known in the art.

[0017] The photolysis loaded catalyst of the present application uses active ligand imidazoline and polyvinyl or divinylbenzene copolymerization to prepare a porous copolymer material containing imidazoline, and then iridium or niobium is coordinated to prepare a supported iridium or niobium complex catalyst.

[0018] The key step of the photocatalytic process is to inhibit the recombination of electrons and holes, and O2 adsorbed on the surface of the photocatalyst can prevent the recombination of electrons and holes by capturing electrons to form peroxide ions, and the peroxide ions and hydrogen peroxide will produce hydroxyl radicals to oxidize and degrade the organic amine degradation products.

[0019] .

[0020] The photocatalytic oxidation and reduction reaction of the application adopts transition metal iridate and niobate, has good stability and catalytic activity, and the transition metal iridium is expensive. In order to prevent the loss of the transition metal catalyst during use, the transition metal is loaded on a composite material by a chemical bond, and the composite material is made into a porous polymer. The porous polymer provides the contact area between the organic amine degradation product and the photocatalytic reaction, and improves the reaction efficiency.

[0021] The method of the application is subjected to photocatalytic and catalytic oxidation, and the COD in the organic amine degradation product is continuously degraded in cycles. The COD content of the product after reaction is determined, the cycle number is determined according to the COD content, the COD removal rate is improved, and the purpose of complete mineralization of the organic amine degradation product is also achieved. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 The figure is a flowchart of the method of the embodiment of the application. EMBODIMENT

[0023] The content of the method of the application is further described below in combination with examples.

[0024] When evaluating the oxidation treatment effect, the COD removal rate is used to represent the good or bad. The method specified in the national standard GB11914-89 is used for the detection of COD.

[0025] The porous copolymer material containing imidazoline is prepared by using active ligand imidazoline and polyvinyl or divinylbenzene copolymerization. A certain amount of iridate or niobate is added to the porous copolymer material according to the weight, and the photocatalytic catalyst with different contents is prepared. The content of iridium or niobium in the photocatalytic catalyst is quantitatively analyzed by using a spectrum analyzer, and the specific surface area of the porous copolymer material is determined by using GB / T 19587-2004 “Gas adsorption BET method for determining the specific surface area of solid materials”.

[0026] Example 1: The high-concentration COD organic amine degradation product of a factory has a COD concentration of about 58000 mg / L. 1 m 3 of the organic amine degradation product is added to the COD treatment device, the iridium-based photocatalytic catalyst is used, the content of iridium is 4.9% (wt), the surface area is 410 m 2 3 / m 3 , and the COD is reduced to about 14000 mg / L after the oxidation degradation of the photocatalytic reactor and the oxidation reactor.

[0027] (2) Test conditions

[0028] Reaction temperature: ~40 o C

[0029] Photocatalytic irradiation light power: 300 w

[0030] Solution circulation amount: 200 L / h.

[0031] Example 2: A high concentration COD organic amine degradation product of a factory, the COD concentration of the organic amine degradation product is about 58000 mg / L, 1 m 3 of the organic amine degradation product is added into the COD treatment device, a niobium-based photocatalyst is used, the measured iridium content is 5.1% (wt), the measured surface area is 423 m 2 / m 3 , and the COD is reduced to about 16000 mg / L through the photocatalytic reactor oxidation reactor oxidation degradation.

[0032] (2) Test conditions

[0033] Reaction temperature: ~ 40 o C

[0034] Photolysis irradiation light power: 300 w

[0035] Solution circulation amount: 200 L / h.

[0036] Example 3: A high concentration COD organic amine degradation product of a factory, the COD concentration of the organic amine degradation product is about 58000 mg / L, 1 m 3 of the organic amine degradation product is added into the COD treatment device, and the COD is reduced to about 4000 mg / L through the iridium-based photocatalytic reactor and the catalytic oxidation reactor oxidation degradation.

[0037] (2) Test conditions

[0038] Reaction temperature: ~ 40 o C

[0039] Photolysis irradiation light power: 300 w

[0040] Ozone concentration: 25 mg / L

[0041] Ozone gas inlet amount: 1.5 L / min

[0042] Solution circulation amount: 200 L / h.

[0043] Example 4: A high concentration COD organic amine degradation product of a factory, the COD concentration of the organic amine degradation product is about 58000 mg / L, 1 m 3 of the organic amine degradation product is added into the COD treatment device, and the COD is reduced to about 3000 mg / L through the iridium-based photocatalytic reactor and the catalytic oxidation reactor oxidation degradation.

[0044] (2) Test conditions

[0045] Reaction temperature: ~ 40 o C

[0046] Photolysis irradiation light power: 350w

[0047] Ozone concentration: 30mg / L

[0048] Ozone gas inlet amount: 2.0 L / min

[0049] Solution circulation amount: 200 L / h.

[0050] Example 5: A high concentration COD organic amine degradation product of a factory, the COD concentration of the organic amine degradation product is about 58000mg / L, 1m 3 of the organic amine degradation product is added into the COD treatment device, and the COD is reduced to about 2000mg / L through the niobium-based photocatalytic reactor and the catalytic oxidation reactor.

[0051] (2) Test conditions

[0052] Reaction temperature: ~ 40 o C

[0053] Photolysis irradiation light power: 500w

[0054] Ozone concentration: 30mg / L

[0055] Ozone gas inlet amount: 2.5 L / min

[0056] Solution circulation amount: 180 L / h.

[0057] Example 6: A high concentration COD organic amine degradation product of a factory, the COD concentration of the organic amine degradation product is about 58000mg / L, 1m 3 of the organic amine degradation product is added into the COD treatment device, and the COD is reduced to about 17000mg / L through the iridium-based photocatalytic reactor.

[0058] (2) Test conditions

[0059] Reaction temperature: ~ 40 o C

[0060] Photolysis irradiation light power: 500w

[0061] Polymer surface area: 306m 2 / m 3

[0062] Solution circulation amount: 220 L / h.

[0063] Example 7: A high concentration COD organic amine degradation product from a factory, the COD concentration of the organic amine degradation product is about 58000 mg / L, 1 m 3 of the organic amine degradation product is added to the COD treatment device, and the COD is reduced to about 12000 mg / L by the oxidation and degradation of the iridium-based photocatalytic reactor.

[0064] (2) Test conditions

[0065] Reaction temperature: ~ 40 o C

[0066] Photolysis irradiation light power: 500w

[0067] Polymer surface area: 601 m 2 / m 3

[0068] Solution circulation amount: 220 L / h.

[0069] Example 8: A high concentration COD organic amine degradation product from a factory, the COD concentration of the organic amine degradation product is about 58000 mg / L, 1 m 3 of the organic amine degradation product is added to the COD treatment device, and the COD is reduced to about 600 mg / L by the oxidation and degradation of the iridium-based photocatalytic reactor and the catalytic oxidation reactor.

[0070] (2) Test conditions

[0071] Reaction temperature: ~ 40 o C

[0072] Photolysis irradiation light power: 500w

[0073] Ozone concentration: 30 mg / L

[0074] Ozone gas inlet amount: 2.5 L / min

[0075] Solution circulation amount: 150 L / h.

[0076] Example 9: The reaction product of Example 8 is used for secondary circulation, and the COD is reduced to about 3 mg / L by the oxidation and degradation of the iridium-based photocatalytic reactor and the catalytic oxidation reactor.

[0077]

[0078] (2) Test conditions

[0079] Reaction temperature: ~ 40 o C

[0080] Photolysis irradiation light power: 500w

[0081] ​Ozone concentration: 30 mg / L

[0082] Ozone gas inlet amount: 2.5 L / min

[0083] Solution circulation amount: 200 L / h.

[0084] Example 10: Using the reaction product of Example 9, three cycles were performed, and COD was not detected by the oxidation degradation of the iridium-based photocatalytic reactor and catalytic oxidation reactor.

[0085] (2) Test conditions

[0086] Reaction temperature: ~ 40 o C

[0087] Photolysis irradiation light power: 500 w

[0088] Ozone concentration: 30 mg / L

[0089] Ozone gas inlet amount: 0.5 L / min

[0090] Solution circulation amount: 600 L / h.

Claims

1. A process for the catalytic treatment of degradation products of organic amines, characterized in that The organic amine degradation product is decomposed by using a porous composite material loaded photolysis catalyst, and the decomposed degradation product is subjected to catalytic oxidation decomposition of organic pollutants by ozone, so that COD is continuously removed in a cycle; the porous composite material is a porous polymer of polyvinyl or divinyl benzene, the specific surface area of the porous polymer is 100-600 m 2 / m 3 ; the photolysis catalyst is prepared by copolymerization of an active ligand imidazoline and polyvinyl or divinyl benzene to obtain a porous copolymer material containing imidazoline, and a certain amount of iridate or niobate is added according to the weight of the porous copolymer material to prepare a photolysis catalyst with different contents.

2. The method of claim 1, wherein, The organic amine degradation product from the circulating tank enters the photocatalytic reactor, is decomposed by the photolysis catalyst, enters the catalytic oxidation reactor, and is catalytically oxidized and decomposed by ozone to remove the organic pollutants, and the cycle is continuously processed to improve the COD removal rate.

3. The method of claim 1, wherein, The porous polymer has a specific surface area of 300-550 m 2 / m 3 .

4. The method of claim 1, wherein, The photocatalytic reactor is provided with photolysis irradiation light, and the wavelength range of the irradiation light is 300-400 nm.

5. The method of claim 4, wherein, The photolysis irradiation light is a mercury lamp with a power of 10-500 W.

6. The method of claim 5, wherein, The power is 100-400 W.

7. The method of claim 2, wherein, The catalytic oxidation reactor is provided with a liquid inlet, an ozone injection inlet and a waste gas outlet.

8. The method of claim 2, wherein, The circulating tank, the photocatalytic reactor and the catalytic oxidation reactor are provided with a circulating pump and a flow regulating valve.

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