Particle electrode and method of manufacture and electrofenton device

Abstract

The embodiment of the application provides a particle electrode, a preparation method and an electro-Fenton device. The particle electrode is formed by compounding FeOCl / MoS2 / Cu2S, and the mass ratio of FeOCl / MoS2 / Cu2S is 1:1-3:1-5. The electro-Fenton device comprises an anode plate, a cathode plate and a particle electrode formed by compounding FeOCl / MoS2 / Cu2S, and the particle electrode is arranged between the anode plate and the cathode plate to form a three-dimensional heterogeneous electro-Fenton system. The Cu2S and FeOCl double Fenton reaction centers of the particle electrode and the double activation of MoS2 and Cu2S are utilized to effectively promote the rapid cyclic transformation of Cu and Fe in the particle electrode, improve the catalytic rate of the oxidant in the electro-Fenton process, and improve the current utilization efficiency. Moreover, the electro-Fenton process has a wide pH range, a small amount of sludge, a short reaction time and a high COD removal efficiency.

Description

TECHNICAL FIELD

[0001] The present application relates to the sewage treatment technical field, and particularly relates to a particle electrode, a preparation method and an electro-Fenton device. BACKGROUND

[0002] In recent years, with the rapid development of global industrialization and economy, the proportion of industrial wastewater discharge is increasing, and water pollution problems are becoming increasingly serious. Among them, the organic pollutants in industrial wastewater have the characteristics of multiple types, high toxicity and difficult to decompose, and have become the main pollutants of current wastewater. At present, the methods for treating organic pollutants in industrial wastewater mainly include photocatalytic degradation method, biodegradation method, physical adsorption method, Fenton oxidation method, electrochemical oxidation method, etc.

[0003] Among them, electro-Fenton in electrochemical oxidation method is concerned because of its high degradation efficiency, short reaction time and simple operation, but electro-Fenton method has the problems of large energy consumption, reduced current efficiency due to hydrogen and oxygen evolution, pH value needs to be 3.0-3.5, needs to be neutralized in the later stage, generates Fe(OH)3 iron mud which needs to be treated, and limits its application. SUMMARY

[0004] The embodiments of the present application provide a particle electrode, a preparation method and an electro-Fenton device to solve one or more technical problems encountered in the prior art.

[0005] In a first aspect, the embodiments of the present application provide a particle electrode formed by ferric oxychloride / molybdenum disulfide / cuprous sulfide (FeOCl / MoS2 / Cu2S) complex, wherein the mass ratio of the ferric oxychloride / molybdenum disulfide / cuprous sulfide is 1:1-3:1-5.

[0006] In a second aspect, the embodiments of the present application provide a preparation method of the above particle electrode, comprising:

[0007] Preparation of ferric oxychloride (FeOCl) by chemical vapor phase transfer method;

[0008] Mixing the prepared ferric oxychloride with molybdenum disulfide (MoS2) and cuprous sulfide (Cu2S); wherein the particle size of the molybdenum disulfide is 10-30 μm, and the particle size of the cuprous sulfide is 10-20 μm;

[0009] Grinding the mixture by mechanical ball milling method for 10-20 h; wherein the ball milling speed of the mechanical ball milling method is 300-500 rpm;

[0010] Obtaining the particle electrode formed by ferric oxychloride / molybdenum disulfide / cuprous sulfide complex.

[0011] Thirdly, embodiments of the present invention provide an electro-Fenton device, including an anode plate, a cathode plate, and a particle electrode formed by the above-mentioned iron oxychloride / molybdenum disulfide / cuprous sulfide composite, wherein the particle electrode is disposed between the anode plate and the cathode plate to form a three-dimensional heterogeneous electro-Fenton system.

[0012] In a preferred embodiment, the electro-Fenton device further includes an electrochemical reaction tank, a DC power supply, an oxidant dosing system, and an aeration and stirring system. The pH value of the electrochemical reaction tank is 3-7. The oxidant dosing system is used to add oxidant to the electrochemical reaction tank. The anode plate, cathode plate, and particle electrode are disposed in the electrochemical reaction tank, and the anode plate and cathode plate are connected to the DC power supply. The aeration and stirring system is used to aerate the electrochemical reaction tank.

[0013] In a preferred embodiment, the oxidant comprises hydrogen peroxide and / or persulfate.

[0014] In a preferred embodiment, the content of the particle electrode formed by the iron oxychloride / molybdenum disulfide / cuprous sulfide composite is 100-1200 g / L.

[0015] In a preferred embodiment, the chemical oxygen demand in the electrochemical reaction tank is 200–20000 mg / L.

[0016] One of the above technical solutions has the following advantages or beneficial effects:

[0017] The present invention relates to an iron oxychloride / molybdenum disulfide / cuprous sulfide (FeOCl / MoS2 / Cu2S) particle electrode, which, under the influence of an electric field, can form heterogeneous dual Fenton reaction centers of cuprous sulfide (Cu2S) and iron oxychloride (FeOCl). Furthermore, the iron oxychloride / molybdenum disulfide / cuprous sulfide (FeOCl / MoS2 / Cu2S) particle electrode is prepared in a one-step mechanical ball milling method. This method is simple, avoids acid-base addition, heating reactions, and high-temperature calcination, and the prepared particle electrode has high catalytic efficiency. In the electro-Fenton device, the oxidant accelerates the reaction with Cu at the solid interface of the particle electrode. + and Fe 2+ The dual-catalytic reaction reduces FeO2 to strongly oxidizing hydroxyl radicals and / or sulfate radicals, while molybdenum disulfide (MoS2) and cuprous sulfide (Cu2S) in the particle electrode dual-activate FeO2 in FeOCl. 3+ / Fe 2+ Cu in Cu2S 2+ / Cu + Rapid conversion significantly improves the Fenton reaction rate, and features high catalytic activity, low sludge production, good conductivity, and high current utilization efficiency. It can effectively remove organic pollutants from water under neutral pH conditions.

[0018] The above summary is intended to illustrate only and is not intended to be limiting in any way. Further aspects, implementations, and features of the application will be apparent from the drawings and the following detailed description. BRIEF DESCRIPTION OF DRAWINGS

[0019] In the drawings, like reference numerals refer to same or similar components throughout the several views. The drawings are not necessarily to scale. It should be understood that the drawings only depict some embodiments of the application and do not imply any limitation of scope for the application.

[0020] Figure 1 The structure schematic diagram of electro-Fenton device in the embodiment of the application.

[0021] Figure 2 The effect diagram of removing pollutants by heterogeneous electro-Fenton based on FeOCl / MoS2 / Cu2S electrode particles under different pH values in the third embodiment of the application.

[0022] Figure 3 The effect diagram of removing pollutants by heterogeneous electro-Fenton based on FeOCl / MoS2 / Cu2S electrode particles under different pH values in the third embodiment of the application.

[0023] Figure 4 The effect diagram of removing pollutants by heterogeneous electro-Fenton based on FeOCl / MoS2 / Cu2S electrode particles under different H2O2 dosages in the fourth embodiment of the application.

[0024] Figure 5 The effect diagram of removing pollutants by heterogeneous electro-Fenton based on FeOCl / MoS2 / Cu2S electrode particles under different salt components in the fifth embodiment of the application.

[0025] REFERENCE NUMERALS

[0026] Electrochemical reaction tank 1; anode plate 2; cathode plate 3; direct current power supply 4;

[0027] Aeration stirring system 5; particle electrode 6; water inlet 7; water outlet 8;

[0028] Oxidant dosing system 9; acid and alkali dosing system 10; online pH meter 11. DETAILED DESCRIPTION

[0029] In the following, only certain exemplary embodiments are simply described. As those skilled in the art can recognize, the described embodiments can be modified in various different ways without departing from the spirit or scope of the present application. Therefore, the drawings and the description are considered to be exemplary in nature rather than limiting.

[0030] In a first aspect, the embodiments of the present application provide a particle electrode formed by ferric oxychloride / molybdenum disulfide / cuprous sulfide (FeOCl / MoS2 / Cu2S) complex, wherein the mass ratio of ferric oxychloride / molybdenum disulfide / cuprous sulfide is 1:1-3:1-5.

[0031] The ferric oxychloride / molybdenum disulfide / cuprous sulfide (FeOCl / MoS2 / Cu2S) particle electrode of the embodiments of the present application can form cuprous sulfide (Cu2S) and ferric oxychloride (FeOCl) heterogeneous dual Fenton reaction centers under the action of an electric field.

[0032] In a second aspect, the embodiments of the present application provide a preparation method of the above particle electrode, comprising:

[0033] Preparation of ferric oxychloride (FeOCl) by chemical vapor migration method;

[0034] Mixing the prepared ferric oxychloride with molybdenum disulfide (MoS2) and cuprous sulfide (Cu2S), wherein the particle size of molybdenum disulfide is 10-30 μm, and the particle size of cuprous sulfide is 10-20 μm;

[0035] Grinding the mixture by mechanical ball milling method for 10-20 h, wherein the ball milling speed of the mechanical ball milling method is 300-500 rpm;

[0036] Obtaining the particle electrode formed by ferric oxychloride / molybdenum disulfide / cuprous sulfide complex.

[0037] The ferric oxychloride / molybdenum disulfide / cuprous sulfide (FeOCl / MoS2 / Cu2S) particle electrode of the embodiments of the present application is prepared by one-step mechanical ball milling method, which is simple in process, avoids acid-base addition, heating reaction and high-temperature calcination process, and has high catalytic efficiency

[0038] Example 1

[0039] The present application provides a preparation method of ferric oxychloride / molybdenum disulfide / cuprous sulfide particle electrode, which comprises the following steps: mixing MoS2, Cu2S and FeOCl powders in a mass ratio of 1:1:1, preparing raw material FeOCl by chemical vapor migration method, the particle size of MoS2 is 10-30 μm, the particle size of Cu2S is 10-20 μm, grinding by mechanical ball milling method for 20 h, the ball milling speed is 300-500 rpm, and obtaining product FeOCl / MoS2 / Cu2S particle electrode.

[0040] In a third aspect, the embodiments of the present application provide an electro-Fenton device, as shown in Figure 1 The electro-Fenton device comprises an anode plate 2, a cathode plate 3, and a particle electrode 6 formed by a composite of iron oxychloride / molybdenum disulfide / cuprous sulfide, wherein the particle electrode 6 is arranged between the anode plate 2 and the cathode plate 3 to form a three-dimensional heterogeneous electro-Fenton system.

[0041] Further, as shown in Figure 1 The electro-Fenton device further comprises an electrochemical reaction tank 1, a direct current power supply 4, an aeration stirring system 5, a water inlet 7, a water outlet 8, an oxidant adding system 9, an acid-alkali adding system 10, and an online pH meter 11. The water inlet 7 and the water outlet 8 are arranged on both sides of the electrochemical reaction tank, the pH value in the electrochemical reaction tank 1 is maintained at 3-7, the pH value is measured by using the online pH meter 11, the acid-alkali adding system 10 is used for adding acid-alkali reagents for pH adjustment, the oxidant adding system 9 is used for adding oxidants to the electrochemical reaction tank 1, the anode plate 2, the cathode plate 3, and the particle electrode 6 are arranged in the electrochemical reaction tank 1, and the anode plate 2 and the cathode plate 3 are connected with the direct current power supply 4, and the aeration stirring system 5 is used for aeration of the electrochemical reaction tank 1.

[0042] In the electro-Fenton device, the oxidant accelerates the reduction of Cu + and Fe 2+ in the solid interface of the particle electrode to strong oxidizing hydroxyl radicals and / or sulfate radicals, while the molybdenum disulfide (MoS2) and the cuprous sulfide (Cu2S) in the particle electrode activate FeOCl, Fe 3+ / Fe 2+ and Cu2S, Cu 2+ / Cu + are rapidly converted, which significantly improves the Fenton reaction rate, has high catalytic activity, small amount of mud production, good electrical conductivity, high current utilization efficiency, and can effectively remove organic pollutants in water under neutral pH conditions.

[0043] In a specific embodiment, the oxidant comprises hydrogen peroxide and / or persulfate.

[0044] In a specific embodiment, the content of the particle electrode formed by the composite of iron oxychloride / molybdenum disulfide / cuprous sulfide is 100-1200 g / L.

[0045] In a specific embodiment, the chemical oxygen demand (COD) in the electrochemical reaction tank is 200-20000 mg / L.

[0046] Embodiment two

[0047] The application of the three-dimensional heterogeneous electro-Fenton system under different FeOCl / MoS2 / Cu2S particle electrode dosages is illustrated in the following steps:

[0048] Water quality conditions: The biochemical effluent from the pharmaceutical wastewater has a COD of 300 mg / L, a pH of 8.4, and a conductivity of 15 mS / cm. The main process parameters are as follows: The FeOCl / MoS2 / Cu2S particle electrode described in the above examples is used. The three-dimensional electrode process employs a microporous aeration plate at the bottom, with a ruthenium-iridium-titanium electrode plate as the anode and a graphite plate as the cathode. The electrode spacing is 5 cm, and the current density is 4 mA / cm². 2 The H2O2 dosage was 300 mg / L, the pH was 5, and the reaction time was 30 min.

[0049] Depend on Figure 2 It can be seen that the treatment effect of adding a particle electrode is significantly better than that of not adding one, and the COD removal rate increases with the increase of the particle electrode dosage. This is because more hydroxyl radicals are generated in a short time under the catalytic action of more particle electrodes, which increases the COD removal rate. The COD removal rate at 30 min is optimal when the particle electrode dosage is 1000 mg / L.

[0050] Example 3

[0051] The specific steps for applying particle electrodes to treat pharmaceutical wastewater at different pH levels are as follows:

[0052] Water quality conditions: The COD of the biochemical effluent from the pharmaceutical wastewater is 300 mg / L, and the conductivity is 15 mS / cm. The main process parameters are as follows: The particle electrode prepared using the method in Application Example 1 is employed, with a particle electrode packing density of 1000 g / L. A microporous aeration plate is used at the bottom of the three-dimensional electrode process. The anode is a ruthenium-iridium-titanium electrode plate, and the cathode is a graphite plate. The electrode spacing is 5 cm, and the current density is 4 mA / cm². 2 Voltage 3.7V, H2O2 dosage 300mg / L, reaction time 30min.

[0053] Figure 3 The results show that the COD removal rate of the particle electrode reaches over 80% at different pH levels after 30 minutes, indicating that the prepared particle electrode has strong pH adaptability. The optimal COD removal rate after 30 minutes is found at pH 6.

[0054] Example 4

[0055] The application of particle electrode treatment for pharmaceutical wastewater under different H2O2 dosages is illustrated in the following steps:

[0056] Water quality conditions: the COD of the pharmaceutical wastewater was 300 mg / L, and the conductivity was 15 mS / cm. The main process parameters were as follows: the particle electrode prepared by the method of application example 1 was used, the particle electrode filling amount was 1000 g / L, the three-dimensional electrode process bottom used a microporous aeration plate, the anode was a ruthenium iridium titanium electrode plate, the cathode was a graphite plate, the electrode plate spacing was 5 cm, the current density was 4 mA / cm 2 , the voltage was 3.7 V, the pH was 6, and the reaction time was 30 min.

[0057] Figure 4 It was shown that the COD removal rate increased with the increase of the H2O2 dosage, because more H2O2 provided more hydroxyl radicals to oxidize and degrade organic matter, but excessive H2O2 dosage would cause H2O2 residue, resulting in the increase of the effluent COD. The COD removal rate was best at 30 min when the H2O2 dosage was 400 mg / L.

[0058] Example five

[0059] The application of the particle electrode in treating high-salt wastewater under different salt components was as follows:

[0060] Water quality conditions: the salt content of the four different wastewater types was A: 3wt% Na2SO4; B: 2wt% Na2SO4+1wt% NaCl; C: 1wt% Na2SO4+2wt% NaCl; D: 3wt% NaCl, and the concentration of nitrobenzene was 200 mg / L. The main process parameters were as follows: the particle electrode prepared by the method of application example 1 was used, the particle electrode filling amount was 1000 g / L, the three-dimensional electrode process bottom used a microporous aeration plate, the anode was a ruthenium iridium titanium electrode plate, the cathode was a graphite plate, the electrode plate spacing was 5 cm, the current density was 4 mA / cm 2 , the voltage was 3.7 V, the H2O2 dosage was 400 mg / L, the pH was 6, and the reaction time was 30 min.

[0061] Figure 5 It was shown that the pollutant removal rate reached 100% under different salt contents, and the COD removal rate was more than 94%, indicating that the degradation effect of the prepared particle electrode was almost not affected by the chloride ion concentration in the wastewater.

[0062] In the description of the present specification, the description of the terms "one embodiment", "some embodiments", "an example", "a specific example", or "some examples" and the like means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. Also, the specific features, structures, materials or characteristics described can be combined in any appropriate manner in any one or more embodiments or examples. In addition, the person skilled in the art can combine and combine the different embodiments or examples described in the specification and the features of the different embodiments or examples without contradiction.

[0063] In addition, the terms "first", "second" are only for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined with "first", "second" can explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "a plurality of" is two or more, unless otherwise specifically limited.

[0064] The above is only a specific embodiment of the present application, but the protection scope of the present application is not limited thereto, and any person skilled in the art can easily think of various changes or replacements within the technical scope disclosed by the present application, which should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A particle electrode, characterized by, The ferric oxychloride / molybdenum disulfide / cuprous sulfide composite is formed by mixing ferric oxychloride, molybdenum disulfide and cuprous sulfide, wherein the mass ratio of the ferric oxychloride / molybdenum disulfide / cuprous sulfide is 1:1-3:1-5. The ferric oxychloride is prepared by a chemical vapor phase transfer method. The prepared ferric oxychloride is mixed with molybdenum disulfide and cuprous sulfide, wherein the particle size of the molybdenum disulfide is 10-30 μm, and the particle size of the cuprous sulfide is 10-20 μm. The mixture is ground by a mechanical ball milling method for 10-20 h, wherein the ball milling speed of the mechanical ball milling method is 300-500 rpm. A particle electrode of the ferric oxychloride / molybdenum disulfide / cuprous sulfide composite is obtained.

2. An electro-Fenton device characterized in that, The particle electrode is arranged between the anode plate and the cathode plate to form a three-dimensional heterogeneous electro-Fenton system.

3. The electro-Fenton device of claim 2, wherein the cathode is a stainless steel cathode. The electrochemical reaction tank, the direct current power supply, the oxidant adding system and the aeration stirring system are further included, the pH value in the electrochemical reaction tank is 3-7, the oxidant adding system is used for adding the oxidant into the electrochemical reaction tank, the anode plate, the cathode plate and the particle electrode are arranged in the electrochemical reaction tank, the anode plate and the cathode plate are connected with the direct current power supply, and the aeration stirring system is used for aerating the electrochemical reaction tank.

4. The electro-Fenton device of claim 3, wherein the cathode is a stainless steel cathode. The oxidant includes hydrogen peroxide and / or persulfate.

5. The electro-Fenton device of claim 3, wherein the cathode is a stainless steel cathode. The content of the particle electrode is 100-1200 g / L.

6. The electro-Fenton device of claim 3, wherein the cathode is a stainless steel cathode. The chemical oxygen demand in the electrochemical reaction tank is 200-20000 mg / L.

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