Method and device for electrolysis of self-cleaning composite graphite electrode

Abstract

The invention relates to a method and a device for electrolysis of a self-cleaning composite graphite electrode, and belongs to the technical field of electrochemical electrolysis. The device is a periodic turning electrolyzer comprising an electrolysis bath, a periodic turning controller and a direct current supply system, wherein the positive electrode and the negative electrode are made of insoluble metal; a graphite or glass carbon complex pole is arranged in the middle; and the periodic turning controller realizes the circulating operations of power turn-on, power turn-off, turning power turn-on and power turn-off. The electrolysis method comprises the following steps: (1) materials are fed into the electrolysis bath, wherein the electric conductivity for the electrolyzed materials is larger than 0.1 S / m; (2) the periodic turning controller is adjusted; and (3) power is turned on to carry out electrolytic oxidation reduction reaction. The method and the device can realize self-cleaning of the electrode in the electrolytic oxidation reduction process, improve the electrolysis efficiency and reduce the electrolysis energy consumption and are easy for industrial implementation.

Description

technical field

[0001] The invention relates to the technical field of electrochemical electrolysis, in particular to a self-cleaning composite electrode electrolysis method and device. technical background

[0002] The basic principle of electrochemical electrolysis water treatment technology is to generate hydroxyl radicals (OH), ozone (O 3 ), hydrogen peroxide (H 2 o 2 ), hypochlorite (ClO - ), Chlorine (Cl 2 ) or atomic oxygen and other strong oxidants, and then degrade the pollutants in the wastewater. Electrochemical electrolysis technology is an advanced oxidation technology. As an "environmentally friendly technology", electrochemical electrolysis treatment has been widely studied and applied in the treatment of some refractory biodegradable pollutants. As a cleaning treatment process, electrochemical electrolysis is highly flexible and can be applied alone or in combination with other treatment methods.

[0003] Electrochemical electrolysis is an oxidation-red...

Examples

Embodiment 1

[0038] As shown in the attached figure, the self-cleaning composite electrode electrolysis adopts a periodic steering electrolysis device. The electrolysis device includes: an electrolytic cell, a cycle steering controller, and a DC power supply system. The positive and negative electrodes of the electrolytic cell are graphite, and the thickness is 5mm. It is a flat plate structure , there is a graphite repolarization in the middle, the outer diameter of the particles is about 1.5mm, and they are piled up in bulk. The distance between the insoluble metal electrode plates in the electrolytic cell is 10mm, and the distance between the graphite repolarization and the positive and negative electrode plates in the middle is 1mm, using plastic wire The grid is isolated so that the repolarization cannot contact the positive and negative electrodes. The cycle steering controller realizes the cyclic operation of energization-disconnection-steering energization-disconnection. The cycle s...

Embodiment 2

[0044] The difference from Example 1 is that the thickness of the positive and negative electrode plates is 8 mm, the outer diameter of graphite particles is about 3.5 mm, the distance between the electrode plates is 50 mm, and the distance between the repolarization electrode and the positive and negative electrode plates set in the middle is 2 mm.

[0045] Electrolysis method steps: 1) Use 15% sodium hydroxide solution to adjust the pH value to 3, and use sodium sulfate to adjust the conductivity to 0.7S / m; 2) The steering cycle is 80 seconds, and the ratio of disconnection time to power-on time is 1: 4; 3) Current density 10A / m 2 .

[0046] After 10 hours of electrolysis, the electrode was taken out, rinsed and dried with deionized water, and observed with an electron microscope at 5000 times. It can be seen that one side of the electrode is the same as the new electrode, and the other side has polymer adsorption. The positive and negative poles of the electrode are switch...

Embodiment 3

[0048]The difference from Example 1 is that the thickness of the positive and negative electrode plates is 15 mm, the outer diameter of graphite particles is about 5 mm, the distance between the electrode plates is 100 mm, and the distance between the repolarization electrode and the positive and negative electrode plates set in the middle is 3 mm.

[0049] Dye industrial wastewater, COD is 2465mg / L, conductivity of electrolyzed material is 2308μs / cm, pH value is 4.6.

[0050] Electrolysis method steps: 1) Do not adjust the pH value, use sodium sulfate to adjust the conductivity to 0.3S / m; 2) The steering cycle is 120 seconds, and the ratio of disconnection time to power-on time is 1:2; 3) Current density is 15A / m 2 .

[0051] After 4 hours of electrolysis, take out the material and replace it with a new one. After repeating 5 times, take out the electrode, rinse and dry it with deionized water, and observe it with an electron microscope at 5000 times. It can be seen that one ...

technical field

[0001] The invention relates to the technical field of electrochemical electrolysis, in particular to a self-cleaning composite electrode electrolysis method and device. technical background

[0002] The basic principle of electrochemical electrolysis water treatment technology is to generate hydroxyl radicals (OH), ozone (O 3 ), hydrogen peroxide (H 2 o 2 ), hypochlorite (ClO - ), Chlorine (Cl 2 ) or atomic oxygen and other strong oxidants, and then degrade the pollutants in the wastewater. Electrochemical electrolysis technology is an advanced oxidation technology. As an "environmentally friendly technology", electrochemical electrolysis treatment has been widely studied and applied in the treatment of some refractory biodegradable pollutants. As a cleaning treatment process, electrochemical electrolysis is highly flexible and can be applied alone or in combination with other treatment methods.

[0003] Electrochemical electrolysis is an oxidation-red...

Examples

Embodiment 1

[0038] As shown in the attached figure, the self-cleaning composite electrode electrolysis adopts a periodic steering electrolysis device. The electrolysis device includes: an electrolytic cell, a cycle steering controller, and a DC power supply system. The positive and negative electrodes of the electrolytic cell are graphite, and the thickness is 5mm. It is a flat plate structure , there is a graphite repolarization in the middle, the outer diameter of the particles is about 1.5mm, and they are piled up in bulk. The distance between the insoluble metal electrode plates in the electrolytic cell is 10mm, and the distance between the graphite repolarization and the positive and negative electrode plates in the middle is 1mm, using plastic wire The grid is isolated so that the repolarization cannot contact the positive and negative electrodes. The cycle steering controller realizes the cyclic operation of energization-disconnection-steering energization-disconnection. The cycle s...

Embodiment 2

[0044] The difference from Example 1 is that the thickness of the positive and negative electrode plates is 8 mm, the outer diameter of graphite particles is about 3.5 mm, the distance between the electrode plates is 50 mm, and the distance between the repolarization electrode and the positive and negative electrode plates set in the middle is 2 mm.

[0045] Electrolysis method steps: 1) Use 15% sodium hydroxide solution to adjust the pH value to 3, and use sodium sulfate to adjust the conductivity to 0.7S / m; 2) The steering cycle is 80 seconds, and the ratio of disconnection time to power-on time is 1: 4; 3) Current density 10A / m 2 .

[0046] After 10 hours of electrolysis, the electrode was taken out, rinsed and dried with deionized water, and observed with an electron microscope at 5000 times. It can be seen that one side of the electrode is the same as the new electrode, and the other side has polymer adsorption. The positive and negative poles of the electrode are switch...

Embodiment 3

[0048]The difference from Example 1 is that the thickness of the positive and negative electrode plates is 15 mm, the outer diameter of graphite particles is about 5 mm, the distance between the electrode plates is 100 mm, and the distance between the repolarization electrode and the positive and negative electrode plates set in the middle is 3 mm.

[0049] Dye industrial wastewater, COD is 2465mg / L, conductivity of electrolyzed material is 2308μs / cm, pH value is 4.6.

[0050] Electrolysis method steps: 1) Do not adjust the pH value, use sodium sulfate to adjust the conductivity to 0.3S / m; 2) The steering cycle is 120 seconds, and the ratio of disconnection time to power-on time is 1:2; 3) Current density is 15A / m 2 .

[0051] After 4 hours of electrolysis, take out the material and replace it with a new one. After repeating 5 times, take out the electrode, rinse and dry it with deionized water, and observe it with an electron microscope at 5000 times. It can be seen that one ...

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