Method for removing carbamazepine in water by using vacuum ultraviolet activated ferrate

Abstract

The invention relates to a method for removing carbamazepine in water by using vacuum ultraviolet activated ferrate, aiming at solving the problems that the ferrate is weak in capability of oxidizing carbamazepine under neutral and alkaline conditions and the utilization rate of the capability of oxidizing pollutants is low when the ferrate and a strong complex coexist, and the like. The method for removing carbamazepine in water comprises the following steps: 1, adjusting the pH value of wastewater containing carbamazepine to 7-9; 2, putting a vacuum ultraviolet lamp into a glass cover, and then immersing the glass cover into the wastewater of which the pH value is adjusted; and 3, adding ferrate into the wastewater of which the pH value is adjusted, carrying out radiation trigger reaction on the wastewater of which the pH value is adjusted by virtue of a preheated vacuum ultraviolet lamp, and simultaneously carrying out stirring reaction, so that the degradation of carbamazepine in the water is realized. According to the method, vacuum ultraviolet is combined with a ferrate oxidation technology, intermediate-state iron substances and hydroxyl free radicals generated in a system are used for rapidly degrading carbamazepine in water, and the removal rate of carbamazepine in water reaches 90% or above.

Description

Technical Field

[0001] The present invention belongs to the field of water treatment, and particularly relates to a method for removing carbamazepine in water by activating ferrate with vacuum ultraviolet light. Background Art

[0002] Pharmaceuticals and personal care products (PPCPs) are a new type of pollutants that have emerged in recent years. Although the concentration of such pollutants is relatively low, they have complex structures and strong biological activities, and their potential hazards cannot be ignored. Among them, carbamazepine, as a typical anti-epileptic drug, is one of the most representative PPCPs substances. Due to the wide use of carbamazepine at present, it is discharged into the water environment in large quantities. Carbamazepine not only poses a threat to the environment and human health, but also has drug resistance to conventional water treatment processes. Therefore, it is very necessary to study the removal of carbamazepine in water.

[0003] In recent years, ferrate has received extensive attention as a green multifunctional oxidant with application values such as disinfection, oxidation, and flocculation. The strong oxidation ability of ferrate has good degradation effects on the removal of persistent organic compounds (such as pharmaceuticals), microcystins, PPCPs, and endocrine disruptors (EDCs), etc.

[0004] Recently, photo-assisted advanced oxidation processes have been focused on because they do not require additional chemicals and can conveniently upgrade existing water treatment equipment. At present, ultraviolet (UV) irradiation is widely used for disinfection and oxidation in wastewater treatment. Compared with UV, vacuum ultraviolet (VUV) has higher energy and can emit ultraviolet light with wavelengths of 185 and 254 nm. As is well known, 185-nm vacuum ultraviolet light can directly cleave water to generate reactive oxygen species, namely hydroxyl radicals (·OH), and produce a certain concentration of H 2 O 2 . Therefore, VUV, as a green oxidation technology, is receiving extensive attention from researchers. Summary of the Invention

[0005] The purpose of the present invention is to solve the problems that the oxidation ability of ferrate is weak under neutral and alkaline conditions and the utilization rate of the oxidation ability of ferrate is low when it coexists with strong complexes, etc., and to provide a method for removing carbamazepine in water by activating ferrate with vacuum ultraviolet light.

[0006] The method for removing carbamazepine in water by activating ferrate with vacuum ultraviolet light according to the present invention is realized according to the following steps:

[0007] I. Adjust the pH value of the wastewater containing carbamazepine to 7-9 to obtain the wastewater with the adjusted pH.

[0008] II. Turn on the vacuum ultraviolet lamp for preheating. Place the vacuum ultraviolet lamp in a glass cover and then immerse it in the wastewater with adjusted pH to obtain a preheated vacuum ultraviolet lamp.

[0009] III. Add ferrate to the wastewater with adjusted pH. Trigger the reaction by irradiating the wastewater with adjusted pH through the preheated vacuum ultraviolet lamp, and stir the reaction simultaneously to complete the removal of carbamazepine in the water.

[0010] The method for removing carbamazepine in water by using vacuum ultraviolet-activated ferrate according to the present invention has the following beneficial effects:

[0011] (1) Both the vacuum ultraviolet process and ferrate used in the present invention are green and efficient. There are no secondary toxic by-products generated after the reaction, and items such as vacuum ultraviolet lamps and ferrate are easily available and have low costs.

[0012] (2) Under the vacuum ultraviolet radiation of the present invention, the photolysis process of ferrate dominates. More intermediate iron substances, namely tetravalent iron and pentavalent iron, will be generated from ferrate.

[0013] (3) Due to the unique property of vacuum ultraviolet emitting 185 nm light, it can photodegrade H 2 O to generate reactive substances mainly ·OH to degrade carbamazepine.

[0014] (4) The Fe(II) generated from Fe(IV) can react quickly with H 2 O 2 in the system to generate more reactive substances (such as ·OH) to degrade carbamazepine.

[0015] (5) During the process of vacuum ultraviolet coupling with ferrate, Fe(III) is rapidly converted into Fe(II) by light irradiation. Thus, vacuum ultraviolet can also promote the Fe(III) / Fe(II) redox cycle in the system and improve the degradation rate of carbamazepine.

[0016] (6) The combination of vacuum ultraviolet and ferrate can effectively alleviate the problem of weak oxidation ability of ferrate under alkaline conditions (pH > 7.0), and the removal rate of carbamazepine can reach more than 90% within 2 - 10 minutes. Description of the Drawings

[0017] Figure 1 It is a test chart of the degradation effect of VUV / Fe(VI) on carbamazepine (CBZ) with different initial concentrations in the examples. Detailed Embodiments

[0018] Detailed Embodiment 1: The method for removing carbamazepine in water by using vacuum ultraviolet-activated ferrate according to this embodiment is implemented according to the following steps:

[0019] 1. Adjust the pH value of the wastewater containing carbamazepine to 7 - 9 to obtain the wastewater with adjusted pH.

[0020] 2. Turn on the vacuum ultraviolet lamp for preheating. After placing the vacuum ultraviolet lamp in the glass cover, immerse it in the wastewater with adjusted pH to obtain the preheated vacuum ultraviolet lamp.

[0021] 3. Add ferrate to the wastewater with adjusted pH, and trigger the reaction by irradiating the wastewater with adjusted pH through the preheated vacuum ultraviolet lamp while stirring the reaction, thereby completing the removal of carbamazepine in the water.

[0022] In this embodiment, by combining vacuum ultraviolet and ferrate oxidation technologies, the intermediate iron substances and hydroxyl radicals generated in the system are used to rapidly degrade carbamazepine in water, so that the removal rate of carbamazepine reaches more than 90%.

[0023] Specific Embodiment 2: The difference between this embodiment and Specific Embodiment 1 is that in step 1, perchloric acid or 2 mol / L sodium hydroxide solution is used to adjust the pH value of the wastewater containing carbamazepine.

[0024] Specific Embodiment 3: The difference between this embodiment and Specific Embodiment 1 or 2 is that in step 1, the concentration of carbamazepine in the wastewater containing carbamazepine is 5 - 50 μmol / L.

[0025] Specific Embodiment 4: The difference between this embodiment and any one of Specific Embodiments 1 to 3 is that in step 1, the wastewater containing carbamazepine is tap water, drinking surface water, the effluent from the secondary sedimentation tank of a sewage treatment plant or groundwater.

[0026] Specific Embodiment 5: The difference between this embodiment and any one of Specific Embodiments 1 to 4 is that in step 2, the preheating time of the vacuum ultraviolet lamp is 10 - 45 min.

[0027] Specific Embodiment 6: The difference between this embodiment and any one of Specific Embodiments 1 to 5 is that in step 3, the ferrate mentioned is potassium ferrate, sodium ferrate or a mixture of both.

[0028] Specific Embodiment 7: The difference between this embodiment and any one of Specific Embodiments 1 to 6 is that in step 3, the dosing concentration of ferrate is 10 - 200 μmol / L.

[0029] Specific Embodiment 8: The difference between this embodiment and any one of Specific Embodiments 1 to 7 is that in step 3, the irradiation intensity of the preheated vacuum ultraviolet lamp is 1 - 5 mW / cm 2 .

[0030] Specific Embodiment Nine: The difference between this embodiment and any one of Specific Embodiments One to Eight is that in Step 3, the stirring speed of the stirring reaction is controlled at 400 - 800 r / min.

[0031] Specific Embodiment Ten: The difference between this embodiment and any one of Specific Embodiments One to Nine is that in Step 3, the stirring reaction time is 2 - 60 min.

[0032] Example One: The method for removing carbamazepine in water by vacuum ultraviolet activated ferrate in this example is implemented according to the following steps:

[0033] I. Adjust the pH value of the wastewater containing carbamazepine to 8 through a borax buffer solution (concentration: 10 mM). The concentration of carbamazepine in the wastewater containing carbamazepine is 5 μmol / L, and the wastewater with adjusted pH is obtained.

[0034] II. Turn on the vacuum ultraviolet lamp and preheat it for 30 min to maintain a stable output power. Place the vacuum ultraviolet lamp in a glass cover and immerse it in the wastewater with adjusted pH to obtain a preheated vacuum ultraviolet lamp.

[0035] III. Add ferrate to the wastewater with adjusted pH. The dosing concentration of ferrate is 50 μmol / L. The preheated vacuum ultraviolet lamp irradiates and triggers the reaction in the wastewater with adjusted pH, and at the same time, quickly stirs the reaction at a speed of 500 r / min for 30 min, thereby completing the removal of carbamazepine in the water.

[0036] According to Figure 1 As shown, in this example, the wastewater is treated by the method of vacuum ultraviolet activated ferrate, and the degradation efficiency of carbamazepine in the water can reach 100% within 5 min of the reaction.

[0037] Example Two: The method for removing carbamazepine in water by vacuum ultraviolet activated ferrate in this example is implemented according to the following steps:

[0038] I. Adjust the pH value of the wastewater containing carbamazepine to 8 through a borax buffer solution. The concentration of carbamazepine in the wastewater containing carbamazepine is 10 μmol / L, and the wastewater with adjusted pH is obtained.

[0039] II. Turn on the vacuum ultraviolet lamp and preheat it for 30 min to maintain a stable output power. Place the vacuum ultraviolet lamp in a glass cover and immerse it in the wastewater with adjusted pH to obtain a preheated vacuum ultraviolet lamp.

[0040] III. Add ferrate to the wastewater with adjusted pH. The dosing concentration of ferrate is 50 μmol / L. The preheated vacuum ultraviolet lamp irradiates and triggers the reaction in the wastewater with adjusted pH, and at the same time, quickly stirs the reaction at a speed of 500 r / min for 30 min, thereby completing the removal of carbamazepine in the water.

[0041] According to Figure 1 As shown, in this embodiment, the wastewater containing carbamazepine is treated by the method of activating ferrate with vacuum ultraviolet light. After reacting for 5 min, the degradation efficiency of carbamazepine in the water is 91%; after reacting for 10 min, the degradation efficiency of carbamazepine in the water is 100%.

[0042] Example 3: The method for removing carbamazepine from water by activating ferrate with vacuum ultraviolet light in this embodiment is implemented according to the following steps:

[0043] I. Adjust the pH value of the wastewater containing carbamazepine to 8 with a borax buffer solution. The concentration of carbamazepine in the wastewater containing carbamazepine is 15 μmol / L to obtain the wastewater with adjusted pH.

[0044] II. Turn on the vacuum ultraviolet lamp and preheat it for 30 min to maintain a stable output power. Put the vacuum ultraviolet lamp into a glass cover and immerse it in the wastewater with adjusted pH to obtain a preheated vacuum ultraviolet lamp.

[0045] III. Add potassium ferrate to the wastewater with adjusted pH. The dosing concentration of potassium ferrate is 50 μmol / L. The preheated vacuum ultraviolet lamp irradiates the wastewater with adjusted pH to trigger the reaction, and at the same time, quickly stir the reaction at a speed of 500 r / min for 30 min, thereby completing the removal of carbamazepine in the water.

[0046] According to Figure 1 As shown, in this embodiment, the wastewater containing carbamazepine is treated by the method of activating ferrate with vacuum ultraviolet light. After reacting for 5 min, the degradation efficiency of carbamazepine in the water is 74%; after reacting for 15 min, the degradation efficiency of carbamazepine in the water is 97%.

[0047] Example 4: The method for removing carbamazepine from water by activating ferrate with vacuum ultraviolet light in this embodiment is implemented according to the following steps:

[0048] I. Adjust the pH value of the wastewater containing carbamazepine to 8 with a borax buffer solution. The concentration of carbamazepine in the wastewater containing carbamazepine is 20 μmol / L to obtain the wastewater with adjusted pH.

[0049] II. Turn on the vacuum ultraviolet lamp and preheat it for 30 min to maintain a stable output power. Put the vacuum ultraviolet lamp into a glass cover and immerse it in the wastewater with adjusted pH to obtain a preheated vacuum ultraviolet lamp.

[0050] III. Add potassium ferrate to the wastewater with adjusted pH. The dosing concentration of potassium ferrate is 50 μmol / L. The preheated vacuum ultraviolet lamp irradiates the wastewater with adjusted pH to trigger the reaction, and at the same time, quickly stir the reaction at a speed of 500 r / min for 30 min, thereby completing the removal of carbamazepine in the water.

[0051] As shown Figure 1 in this example, the wastewater containing carbamazepine was treated by the method of activating ferrate with vacuum ultraviolet. After reacting for 5 min, the degradation efficiency of carbamazepine in the water was 65%; after reacting for 15 min, the degradation efficiency of carbamazepine in the water was 93%.

[0052] Example 5: The method for removing carbamazepine from water by activating ferrate with vacuum ultraviolet in this example was implemented according to the following steps:

[0053] I. Adjust the pH value of the wastewater containing carbamazepine to 8 with borax buffer solution. The concentration of carbamazepine in the wastewater containing carbamazepine was 30 μmol / L to obtain the wastewater with adjusted pH.

[0054] II. Turn on the vacuum ultraviolet lamp and preheat it for 30 min to maintain a stable output power. Then put the vacuum ultraviolet lamp into a glass cover and immerse it in the wastewater with adjusted pH to obtain the preheated vacuum ultraviolet lamp.

[0055] III. Add potassium ferrate to the wastewater with adjusted pH. The dosing concentration of potassium ferrate was 50 μmol / L. The preheated vacuum ultraviolet lamp irradiated and triggered the reaction on the wastewater with adjusted pH, and at the same time, it was rapidly stirred at a speed of 500 r / min for 30 min to complete the removal of carbamazepine in the water.

[0056] As shown Figure 1 in this example, the wastewater containing carbamazepine was treated by the method of activating ferrate with vacuum ultraviolet. After reacting for 5 min, the degradation efficiency of carbamazepine in the water was 55%; after reacting for 20 min, the degradation efficiency of carbamazepine in the water was 91%.

[0057] Comparative Example 1: The difference between this example and Example 1 was that no vacuum ultraviolet irradiation was carried out, and only ferrate was added.

[0058] After reacting for 2 min in this comparative example, the degradation efficiency of carbamazepine in the water was only 12%; after reacting for 5 min, the degradation efficiency of carbamazepine in the water was 26%. The above results showed that using vacuum ultraviolet could effectively accelerate the removal of carbamazepine in water by ferrate.

Claims

1. A method for removing carbamazepine from water by using vacuum ultraviolet activated ferrate, characterized in that The method for removing carbamazepine from water is achieved by the following steps:

1. adjusting the pH value of the wastewater containing carbamazepine to 7-9 to obtain wastewater with adjusted pH; 2. Turn on the vacuum ultraviolet lamp to preheat, put the vacuum ultraviolet lamp into the glass cover and immerse it in the wastewater with adjusted pH to obtain the preheated vacuum ultraviolet lamp; 3. Add ferrate to the wastewater with adjusted pH value, irradiate the wastewater with adjusted pH value with a preheated vacuum ultraviolet lamp to trigger the reaction, and stir the reaction at the same time, thereby completing the removal of carbamazepine in the water.

2. The method for removing carbamazepine from water by using vacuum ultraviolet activated ferrate according to claim 1, characterized in that In step 1, perchloric acid or 2 mol / L sodium hydroxide solution is used to adjust the pH value of the wastewater containing carbamazepine.

3. The method for removing carbamazepine from water by using vacuum ultraviolet activated ferrate according to claim 1, characterized in that The concentration of carbamazepine in the wastewater containing carbamazepine in step 1 is 5 to 50 μmol / L.

4. The method for removing carbamazepine from water by using vacuum ultraviolet activated ferrate according to claim 1, characterized in that The wastewater containing carbamazepine in step 1 is tap water, drinking surface water, effluent from the secondary sedimentation tank of a sewage treatment plant or groundwater.

5. The method for removing carbamazepine from water by using vacuum ultraviolet activated ferrate according to claim 1, characterized in that The preheating time of the vacuum ultraviolet lamp in step 2 is 10 to 45 minutes.

6. The method for removing carbamazepine from water by using vacuum ultraviolet activated ferrate according to claim 1, characterized in that The ferrate described in step 3 is potassium ferrate, sodium ferrate or a mixture of the two.

7. The method for removing carbamazepine from water by using vacuum ultraviolet activated ferrate according to claim 1, characterized in that In step 3, the concentration of ferrate added is 10-200 μmol / L.

8. The method for removing carbamazepine from water by using vacuum ultraviolet activated ferrate according to claim 1, characterized in that The irradiation intensity of the vacuum ultraviolet lamp preheated in step 3 is 1-5 mW / cm 2 .

9. The method for removing carbamazepine from water by using vacuum ultraviolet activated ferrate according to claim 1, characterized in that In step 3, the stirring speed of the stirring reaction is controlled to be 400-800 r / min.

10. The method for removing carbamazepine from water by using vacuum ultraviolet activated ferrate according to claim 1, characterized in that The stirring reaction time in step 3 is 2 to 60 minutes.

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