阅读说明：本技术 光催化电极制备方法、光催化反应器及污染流体处理方法 (Photocatalytic electrode preparation method, photocatalytic reactor and polluted fluid treatment method ) 是由 马东 朱彤 马天津 于 2021-07-20 设计创作，主要内容包括：本发明公开了光催化电极制备方法、光催化反应器及污染流体处理方法,包括以下步骤：提供铜片；将铜片进行预处理去除表面氧化膜干扰；使用阳极氧化法在铜片上制得Cu-(2)O薄膜；通过电化学沉积制得g-C-(3)N-(4)/Cu/Cu-(2)O光催化电极,即得Z型三元光催化电极。以g-C-(3)N-(4)和Cu-(2)O作为Z型光催化体系的两个半反应端,以Cu作为电子-空穴对的复合中心,构建了高活性的Z型异质结,巧妙地设置了“还原脱氯——氧化降解”循环过程,此外对光催化电极板施加一定的外加偏压,能够把光催化的能量优势和电催化的可调控性协同起来,抑制光生电子-空穴对的复合,进而提高光生电子的利用效率,促进有机污染物降解。(The invention discloses a preparation method of a photocatalytic electrode, a photocatalytic reactor and a polluted fluid treatment method, which comprises the following steps: providing a copper sheet; pretreating a copper sheet to remove the interference of a surface oxidation film; production of Cu on copper sheets using anodic oxidation 2 An O film; preparation of g-C by electrochemical deposition 3 N 4 /Cu/Cu 2 And O, forming the Z-shaped ternary photocatalytic electrode. In g-C 3 N 4 And Cu 2 O is used as two half reaction ends of a Z-type photocatalysis system, Cu is used as a recombination center of an electron-hole pair, a Z-type heterojunction with high activity is constructed, a cycle process of 'reduction dechlorination-oxidation degradation' is ingeniously set, in addition, a certain external bias voltage is applied to a photocatalysis electrode plate, the energy advantage of photocatalysis and the controllability of electrocatalysis can be cooperated, the recombination of a photoproduction electron-hole pair is inhibited, the utilization efficiency of photoproduction electrons is further improved, and the degradation of organic pollutants is promoted.)

1. A preparation method of a photocatalytic electrode is characterized by comprising the following steps:

s1, providing a copper sheet;

s2, pretreating the copper sheet to remove the interference of the oxide film on the surface of the copper sheet;

s3, use of an anodePreparing Cu on one side of copper sheet by oxidation method₂An O film;

s4, preparing g-C on the other side of the copper sheet by a liquid phase deposition method₃N₄And (5) forming a film to obtain the Z-shaped ternary photocatalytic electrode.

2. The method for preparing a photocatalytic electrode according to claim 1, wherein the step S2 further includes:

(1) cleaning with cleaning powder: washing the prepared copper sheet by using detergent powder to remove surface stains, and then washing the copper sheet by using deionized water to completely remove the stains on the surface of the copper sheet;

(2) acid washing: placing the copper sheet with the stains removed in a 40% dilute hydrofluoric acid solution for soaking for 30s, acidifying an oxidation layer on the surface of the copper sheet, and immediately washing with deionized water until the residual hydrofluoric acid on the surface of the copper sheet is completely removed;

(3) grinding and polishing: wiping deionized water on a copper sheet, roughly grinding by using 400-mesh abrasive paper, then grinding obviously scratches to be flat by using 1000-mesh abrasive paper, and finally finely grinding by using 2000-mesh abrasive paper for polishing until the copper sheet is smooth and traceless, and placing the polished copper sheet in deionized water for storage for later use;

(4) ultrasonic cleaning: and sequentially soaking the copper sheet stored in the deionized water, the absolute ethyl alcohol, the acetone mixed solution and the deionized water, then transferring the copper sheet to an ultrasonic cleaner for ultrasonic cleaning for 3min, and obtaining the copper sheet with the oxide film removed after the cleaning is finished.

3. The method for preparing a photocatalytic electrode according to claim 2, wherein the step S3 further comprises the steps of:

a1, in an electrolytic cell lined with polyvinyl chloride, taking a pretreated copper sheet as an anode, a platinum sheet as a cathode, Ag/AgCl as a reference electrode, placing one surface of the anode copper sheet opposite to and vertically parallel to the cathode platinum sheet, pasting and covering the other surface of the anode copper sheet by an insulating film, taking a boric acid solution with the concentration of 0.3-0.6 mol/L as an electrolyte, and electrolyzing the surface of the anode to generate Cu₂O-plated film, fillFilling a solution of saturated sodium chloride;

a2, washing the copper sheet loaded with the cuprous oxide film by deionized water, and drying the copper sheet in a forced air drying oven for 20min after washing, wherein the drying temperature is 80-120 ℃, so that the copper sheet loaded with Cu on one surface is obtained₂O film, the other surface still being a copper sheet not oxidized, i.e. Cu/Cu₂And an O-shaped photoelectrode.

4. The method for preparing a photocatalytic electrode according to claim 3, wherein the step S4 further comprises the steps of:

b1, removing Cu/Cu₂Coating a methanol solution of melamine on the surface of the insulating film on one side of the O-shaped photoelectrode, airing, and repeating the coating and airing process for more than 10 times;

b2, in a muffle furnace with nitrogen atmosphere, coating the Cu/Cu of melamine₂Annealing the O-shaped photoelectrode at 550 ℃ for 1h to obtain Cu on one side of the surface of the copper sheet₂O thin film crystallized, the other side gave g-C₃N₄Crystallizing the film to obtain g-C₃N₄/Cu/Cu₂O a photocatalytic electrode.

5. The method for preparing a photocatalytic electrode according to claim 3, wherein the temperature of the sodium chloride solution is 20 to 30 ℃, the deposition voltage is-0.6 to 0.3V, and the deposition time is 10 to 120 s.

6. A photocatalytic reactor comprises a box body and is characterized by comprising a Z-shaped three-way photocatalytic electrode manufactured by the photocatalytic electrode manufacturing method according to any one of claims 1 to 5, wherein a plurality of Z-shaped three-way photocatalytic electrodes are connected to form electrode plates, the electrode plates are connected in the box body, the adjacent electrode plates are arranged in a central symmetry manner, and the electrode plates are Cu₂Cu of one side of O film and adjacent electrode plate₂g-C of opposite side of O film₃N₄One side of the film has g-C with the subsequent adjacent electrode plate₃N₄One side of the film is opposite to the other side, and the electrode plate is arranged between the adjacent electrode plate or the inner wall of the box bodyAnd forming a gallery for treating the contaminated fluid, wherein a turbulator is arranged in the gallery, and the electrode plate is connected with a bias power supply.

7. The photocatalytic reactor of claim 6, characterized in that: the box body is provided with a fluid input port and a fluid output port, the fluid input port and the fluid output port are arranged in a centrosymmetric mode, and the fluid input port and the fluid output port are respectively communicated with the gallery.

8. The photocatalytic reactor of claim 6, characterized in that: the box body is made of transparent glass resistant to halogen corrosion.

9. A method of treating contaminated fluid, comprising: the photocatalytic reactor applied to any one of claims 7-8, comprising the following steps: first, halogenated organic contaminant fluid is introduced through a fluid inlet port in the photocatalytic reactor housing having g-C₃N₄The film gallery realizes reduction dehalogenation under illumination to obtain a dehalogenated organic product; then transferred to both sides containing Cu₂And the O film gallery oxidizes and degrades the dehalogenated organic products under illumination, and the process of 'reduction dehalogenation + oxidative degradation' is repeated for a plurality of times in a plurality of galleries of the photocatalytic reactor and is finally discharged through a fluid outlet, so that the halogenated organic pollutants in the polluted fluid are finally completely degraded.

10. The contaminated fluid treatment method of claim 9, wherein: the halogenated organic pollutant fluid is halogenated organic pollutant waste gas or halogenated organic pollutant waste water.

Technical Field

The invention relates to the technical field of pollution treatment, and particularly belongs to a preparation method of a photocatalytic electrode, a photocatalytic reactor and a method for treating polluted fluid.

Background

The photocatalysis technology is expected to become one of the important technologies for solving the energy and environmental problems in the twenty-first century. The principle of the photocatalysis technology is that active free radicals are generated by utilizing a light irradiation catalyst, and organic pollutants in the environment are degraded and mineralized. The photocatalysis technology has the advantages of environmental protection, thorough pollutant degradation, no secondary pollution and the like, and has great application prospect in the aspect of organic pollutant degradation. However, the industrial application of the photocatalytic technology is limited mainly by the following points: firstly, the photocatalytic reaction is a light excitation reaction, and electron-hole pairs generated by light excitation are easy to recombine, so that the quantum efficiency is low; secondly, the traditional photocatalyst only responds to ultraviolet light and cannot utilize most visible light in sunlight; thirdly, after the heterogeneous photocatalyst degrades organic pollutants, the effective separation of the photocatalyst and a water phase is difficult to realize.

Disclosure of Invention

In order to overcome part of defects in the prior art, the invention provides a photocatalytic electrode preparation method, a photocatalytic reactor and a polluted fluid treatment method, which can effectively purify low-concentration halogen-containing water and have simple structure and convenient use.

The technical scheme provided by the invention is that the preparation method of the photocatalytic electrode comprises the following steps:

s1, providing a copper sheet;

s2, pretreating the copper sheet to remove the interference of the oxide film on the surface of the copper sheet;

s3 preparing Cu on one side of copper sheet by using anodic oxidation method₂An O film;

s4, preparing g-C on the other side of the copper sheet by a liquid phase deposition method₃N₄And (5) forming a film to obtain the Z-shaped ternary photocatalytic electrode.

Further, the step S2 further includes:

(1) cleaning with cleaning powder: washing the prepared copper sheet by using detergent powder to remove surface stains, and then washing the copper sheet by using deionized water to completely remove the stains on the surface of the copper sheet;

(2) acid washing: placing the copper sheet with the stains removed in a 40% dilute hydrofluoric acid solution for soaking for 30s, acidifying an oxidation layer on the surface of the copper sheet, and immediately washing with deionized water until the residual hydrofluoric acid on the surface of the copper sheet is completely removed;

(3) grinding and polishing: wiping deionized water on a copper sheet, roughly grinding by using 400-mesh abrasive paper, then grinding obviously scratches to be flat by using 1000-mesh abrasive paper, and finally finely grinding by using 2000-mesh abrasive paper for polishing until the copper sheet is smooth and traceless, and placing the polished copper sheet in deionized water for storage for later use;

(4) ultrasonic cleaning: and sequentially soaking the copper sheet stored in the deionized water, the absolute ethyl alcohol, the acetone mixed solution and the deionized water, then transferring the copper sheet to an ultrasonic cleaner for ultrasonic cleaning for 3min, and obtaining the copper sheet with the oxide film removed after the cleaning is finished.

Further, the step S3 further includes the following steps:

a1, in an electrolytic cell lined with polyvinyl chloride, taking a pretreated copper sheet as an anode, a platinum sheet as a cathode, Ag/AgCl (filling solution is saturated sodium chloride solution) as a reference electrode, placing one surface of the anode copper sheet opposite to and vertically parallel to the cathode copper sheet, sticking and covering the other surface of the anode copper sheet with an insulating film, taking boric acid solution with the concentration of 0.3-0.6 mol/L as electrolyte, and electrolyzing the surface of the anode to generate Cu₂An O-plating film;

a2, washing the copper sheet loaded with the cuprous oxide film by deionized water, and drying the copper sheet in a forced air drying oven for 20min after washing, wherein the drying temperature is 80-120 ℃, so that the copper sheet loaded with Cu on one surface is obtained₂O film, the other surface still being a copper sheet not oxidized, i.e. Cu/Cu₂And an O-shaped photoelectrode.

Further, the step S4 further includes the following steps:

b1, removing Cu/Cu₂Coating a methanol solution of melamine on the surface of the insulating film on one side of the O-shaped photoelectrode, airing, and repeating the coating and airing process for more than 10 times;

b2, in a muffle furnace with nitrogen atmosphere, coating the Cu/Cu of melamine₂Annealing the O-shaped photoelectrode at 550 ℃ for 1h to obtain Cu on one side of the surface of the copper sheet₂O thin film crystallized, the other side gave g-C₃N₄Crystallizing the film to obtain g-C₃N₄/Cu/Cu₂O a photocatalytic electrode.

Further, the temperature of the sodium chloride solution is 20-30 ℃, the deposition voltage is-0.6-0.3V, and the deposition time is 10-120 s.

The invention also provides a photocatalytic reactor, which comprises the Z-shaped ternary photocatalytic electrode manufactured by the photocatalytic electrode manufacturing method, a plurality of Z-shaped ternary photocatalytic electrodes are connected to form an electrode plate, the electrode plates are connected in the box body, and the centers of the adjacent electrode plates are symmetrically arrangedElectrode plate Cu₂Cu of one side of O film and adjacent electrode plate₂g-C of opposite side of O film₃N₄One side of the film has g-C with the subsequent adjacent electrode plate₃N₄One side of the film is opposite, a gallery for treating polluted fluid is formed between the electrode plate and the adjacent electrode plate or the inner wall of the box body, a turbulator is arranged in the gallery, and the electrode plate is connected with a bias power supply.

Furthermore, a fluid input port and a fluid output port are formed in the box body, the fluid input port and the fluid output port are arranged in a central symmetry mode, and the fluid input port and the fluid output port are respectively communicated with the gallery.

Further, the box body is made of transparent glass resistant to halogen corrosion.

Further, the halogenated organic pollutant fluid is halogenated organic pollutant waste gas or halogenated organic pollutant waste water.

The invention also provides a polluted fluid treatment method, which is applied to the photocatalytic reactor and comprises the following steps: first, a halogenated organic contaminant-contaminated fluid is introduced through a fluid inlet port in the housing having g-C₃N₄The film gallery realizes reduction dehalogenation under illumination; then transferred to both sides containing Cu₂And the O film gallery oxidizes and degrades the dehalogenated organic products under illumination, and the process of 'reduction dehalogenation + oxidative degradation' is repeated for a plurality of times in a plurality of galleries of the photocatalytic reactor and is finally discharged through a fluid outlet, so that the complete degradation of the halogenated organic pollutants in the polluted fluid is finally realized.

Has the advantages that:

1. g-C for photocatalytic electrode plate₃N₄And Cu₂O is used as two half reaction ends of the Z-shaped photocatalysis system, Cu is used as a recombination center of an electron-hole pair, a Z-shaped heterojunction of high-efficiency photocatalysis is constructed, and the cycle process of reduction dechlorination-oxidative degradation is skillfully set.

2. The photocatalytic electrode plate is added with a bias power supply, the photocatalytic pollutant degradation has the advantages that the energy advantage of photocatalysis and the controllability of electrocatalysis are cooperated, a certain external bias voltage is applied to the photocatalytic electrode plate, the transfer of photoproduction electrons is promoted, the recombination of photoproduction electron-hole pairs is inhibited, the utilization efficiency of the photoproduction electrons is further improved, and the degradation of organic pollutants is promoted;

3. the invention adopts a plurality of layers of long and thin galleries, and a turbulator is added in the middle of the galleries, so that the halogenated organic polluted fluid can be in full contact reaction with the photocatalytic electrode plate;

4. the invention uses natural light source and has simple operation, which greatly reduces the operation cost of the photocatalysis reactor.

In order to make the aforementioned and other objects, features and advantages of the invention comprehensible, preferred embodiments accompanied with figures are described in detail below.

Drawings

FIG. 1 is a schematic diagram of the steps of the photocatalytic electrode preparation method of the present invention.

Fig. 2 is a schematic structural view of the photocatalytic reactor.

Detailed Description

While the invention will be described in detail and with reference to the accompanying drawings, it is to be understood that the invention is not limited to the precise embodiments, and that various other changes and modifications may be effected therein by one skilled in the art without departing from the scope or spirit of the invention.

Referring to fig. 1 to 2, a method for preparing a photocatalytic electrode includes the following steps:

s1, providing a copper sheet;

s2, pretreating the copper sheet to remove the interference of the oxide film on the surface of the copper sheet;

s3 preparing Cu on one side of copper sheet by using anodic oxidation method₂An O film;

s4, preparing g-C on the other side of the copper sheet by a liquid phase deposition method₃N₄And (5) forming a film to obtain the Z-shaped ternary photocatalytic electrode.

In the above embodiment, the step S2 further includes:

(1) cleaning with cleaning powder: washing the prepared copper sheet by using detergent powder to remove surface stains, and then washing the copper sheet by using deionized water to completely remove the stains on the surface of the copper sheet;

(2) acid washing: placing the copper sheet with the stains removed in a 40% dilute hydrofluoric acid solution for soaking for 30s, acidifying an oxidation layer on the surface of the copper sheet, and immediately washing with deionized water until the residual hydrofluoric acid on the surface of the copper sheet is completely removed;

(3) grinding and polishing: wiping deionized water on a copper sheet, roughly grinding by using 400-mesh abrasive paper, then grinding obviously scratches to be flat by using 1000-mesh abrasive paper, and finally finely grinding by using 2000-mesh abrasive paper for polishing until the copper sheet is smooth and traceless, and placing the polished copper sheet in deionized water for storage for later use;

(4) ultrasonic cleaning: and sequentially soaking the copper sheet stored in the deionized water, the absolute ethyl alcohol, the acetone mixed solution and the deionized water, then transferring the copper sheet to an ultrasonic cleaner for ultrasonic cleaning for 3min, and obtaining the copper sheet with the oxide film removed after the cleaning is finished.

In the above embodiment, the step S3 further includes the following steps:

a1, in an electrolytic bath lined with polyvinyl chloride, taking a pretreated copper sheet as an anode, a platinum sheet as a cathode, Ag/AgCl (filling solution is saturated sodium chloride solution) as a reference electrode, placing one surface of the anode copper sheet opposite to and vertically parallel to the cathode platinum sheet, pasting and covering the other surface of the anode copper sheet with an insulating film, taking boric acid solution with the concentration of 0.3-0.6 mol/L as electrolyte, and electrolyzing the surface of the anode to generate Cu₂An O-plating film;

a2, washing the copper sheet loaded with the cuprous oxide film by deionized water, and drying the copper sheet in a forced air drying oven for 20min after washing, wherein the drying temperature is 80-120 ℃, so that the copper sheet loaded with Cu on one surface is obtained₂O film, the other surface still being a copper sheet not oxidized, i.e. Cu/Cu₂And an O-shaped photoelectrode.

In the above embodiment, the step S4 further includes the following steps:

b1, removing Cu/Cu₂Insulation on the O-electrode sideCoating a methanol solution of melamine on the surface of the edge film and drying the edge film, wherein the coating and drying processes are repeated for more than 10 times;

b2, in a muffle furnace with nitrogen atmosphere, coating the Cu/Cu of melamine₂Annealing the O-shaped photoelectrode at 550 ℃ for 1h to obtain Cu on one side of the surface of the copper sheet₂O thin film crystallized, the other side gave g-C₃N₄Crystallizing the film to obtain g-C₃N₄/Cu/Cu₂O a photocatalytic electrode.

In the above embodiment, the temperature of the sodium chloride solution is 20-30 ℃, the deposition voltage is-0.6-0.3V, and the deposition time is 10-120 s.

The invention provides a photocatalytic reactor, which comprises a Z-shaped ternary photocatalytic electrode manufactured by the photocatalytic electrode manufacturing method, wherein a plurality of Z-shaped ternary photocatalytic electrodes are connected to form an electrode plate 2, the electrode plates 2 are connected in a box body 1, the adjacent electrode plates 2 are arranged in a central symmetry mode, and Cu in the electrode plates 2₂One side of the O film and Cu of the adjacent electrode plate 2₂g-C of opposite side of O film₃N₄One side of the film has g-C with the subsequent adjacent electrode plate 2₃N₄One side of the film is opposite, a gallery 3 for treating polluted fluid is formed between the electrode plate 2 and the adjacent electrode plate 2 or the inner wall of the box body 1, a turbulator 4 is arranged in the gallery 3, and the electrode plate 4 is connected with a bias power supply 5.

In the above embodiment, the box body 1 is provided with the fluid input port 11 and the fluid output port 12, the fluid input port 11 and the fluid output port 12 are arranged in a central symmetry manner, and the fluid input port 11 and the fluid output port 12 are respectively communicated with the gallery 3.

In the above embodiment, the case 1 is made of transparent glass resistant to halogen corrosion.

In the above embodiment, the halogenated organic pollutant fluid is a halogenated organic pollutant waste gas or a halogenated organic pollutant waste water.

The invention also provides a method for treating the polluted fluid, which is applied to the photocatalytic reactor and the photocatalytic reactorThe method comprises the following steps: first, a halogenated organic contaminant fluid is introduced through a fluid inlet 11 in the housing 1 having g-C₃N₄The film gallery 3 realizes reduction dehalogenation under illumination; then transferred to both sides containing Cu₂And the gallery 3 of the O film is used for oxidizing and degrading the dehalogenated organic product under the illumination, and the process of 'reduction dehalogenation + oxidative degradation' is repeated for a plurality of times in the galleries 3 of the photocatalytic reactor and is finally discharged through the fluid output port 12, so that the complete degradation of the halogenated organic pollutants in the polluted fluid is finally realized. The illumination may be natural light or modulated degradation light, and is not particularly limited herein.

In practical application, the fluid input port 11 and the fluid output port 12 of the photocatalytic reactor are opened under the environment of light irradiation, and the electrode plate 2 is electrified. The flow rate of the waste gas of the halogenated organic pollutants or the waste water of the halogenated organic pollutants is controlled by a flow pump to enter a photocatalytic reactor for advanced treatment, and the waste gas of the halogenated organic pollutants or the waste water of the halogenated organic pollutants enters the box body 1 and is fully contacted with the electrode plate 2 according to the flow direction under the action of the turbulator 4. And (3) the halogenated organic pollutant waste gas or the halogenated organic pollutant waste water starts to degrade, after the reaction is finished, the bias power supply 5 is closed, and the treated gas or water body reaching the detection standard is discharged from the fluid output port 12.

The principle and the implementation mode of the invention are explained by applying specific embodiments in the invention, and the description of the embodiments is only used for helping to understand the method and the core idea of the invention; meanwhile, for a person skilled in the art, according to the idea of the present invention, there may be variations in the specific embodiments and the application scope, and in summary, the content of the present specification should not be construed as a limitation to the present invention.