JPH06218222A - Treatment of organic compound in gas - Google Patents

Abstract

PURPOSE:To treat an organic compound in gas at a low cost by impressing an alternate current between a first and a second electrodes, grounding a third electrode, allowing a direct current to flow from the first and second electrode to the third electrodes via moisture in the gas to electrolyze the moisture, dropping the oxidation-reduction potential and using the moisture having the obtained reduction potential and activated oxygen. CONSTITUTION:The first-third electrodes 3A-3C are arranged, a high frequency alternate current is impressed between the first and second electrodes 3A, 3B, and the third electrode 3C is ground. The treating gas 3 incorporated with moisture is passed through so as to come into contact with the electrodes 3A-3C, and a direct current is allowed to flow through the moisture in the gas 2 from the electrodes 3A, 3B to the electrode 3C to electrolyze the moisture and the oxidation-reduction potential is dropped. The organic compound in the gas 2 is treated with the moisture having the obtained reduction potential and the activated oxygen. Thus, the organic compound in the can be treated at a low cost.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of treating an organic compound contained in a gas such as an exhaust gas from a factory or an exhaust gas exhausted from a muffler of an automobile. is there.

[0002]

2. Description of the Related Art Conventionally, a treatment of an organic compound in a gas has been performed by using a noble metal such as platinum.

[0003]

However, the method of using a noble metal or the like has a problem of high cost.

An object of the present invention is to provide a method for treating an organic compound in a gas which can treat the organic compound in the gas at low cost.

[0005]

The means of the present invention for achieving the above object will be described below.

According to a first aspect of the present invention, there is provided a method of treating an organic compound in a gas, wherein first, second and third electrodes are arranged, an alternating current is applied between the first and second electrodes, and the first and second electrodes are applied. The third electrode is grounded, and a treatment gas containing water is passed so as to touch the first, second, and third electrodes, and the gas is passed from the first and second electrodes to the third electrode. A direct current is passed through the water contained therein, the water is electrolyzed to reduce the redox potential of the water, and the organic compound in the gas is treated with the water having the obtained reduction potential and active oxygen. And

According to a second aspect of the present invention, there is provided a method of treating an organic compound in a gas, wherein first, second, third and fourth electrodes are arranged and an alternating current is applied between the first and second electrodes. , The third and fourth
The electrodes of No. 1 are alternately grounded at a low cycle, and the non-grounded electrodes are set to a positive potential so that the processing gas containing water touches the first, second, third and fourth electrodes. Through
A direct current was passed through the water in the gas to the grounded third or fourth electrode from the first and second electrodes to electrolyze the water to lower the redox potential of the water. The organic compound in the gas is treated with water having a reduction potential and active oxygen.

According to a third aspect of the present invention, there is provided the method for treating an organic compound according to the first or second aspect, wherein an electrode made of a metal that lowers a redox potential is used as the first and second electrodes.

[0009]

When an alternating current is applied between the first and second electrodes and the third electrode is grounded as in claim 1, the moisture in the gas passes from the first and second electrodes to the third electrode through water. A direct current flows and the water is electrolyzed. As a result, the oxidation-reduction potential of the water is lowered to the reduction potential.

When the redox potential of water decreases in this way, an electronic reaction (for example, an ionic bond, a covalent bond, etc.) or a chemical reaction occurs with respect to the organic compound in the gas, and the organic compound coagulates and sinks. In addition, active oxygen is generated by electrolysis of water and reacts with an organic compound in the gas, chemical combustion and the like occur, and free radicals become chemically stable Rasigal. This makes it possible to recover or detoxify the organic compound being vaporized.

When the third and fourth electrodes are used, and these electrodes are alternately grounded at a low cycle and the electrode that is not grounded is set to a positive potential, the third electrode is used during the electrolysis of water. , It is possible to prevent the adhered matter from adhering to the fourth electrode.

When the electrodes made of a metal that lowers the redox potential are used as the first and second electrodes as in claim 3, the reduction potential of water can be efficiently lowered, and the treatment reaction of the organic compound can be performed. It can be done efficiently.

[0013]

Embodiments of the present invention will now be described in detail with reference to the drawings.

FIG. 1 shows a first embodiment of an apparatus for treating an organic compound in a gas used in the present invention. In the figure, 1 is a tube forming a flue 1a, 2 is a gas to be processed which passes through the inside of the tube 1, and 3A, 3B and 3C are arranged in the tube 1 along its inner wall so as to come into contact with the gas 2. These are the first, second and third electrodes. As the first and second electrodes 3A and 3B, electrodes made of a metal such as zinc, aluminum, or lithium that lowers the redox potential are used. The third electrode 3C is grounded. 5 is, for example, a DC power source of 50V to 3000V, and 6A and 6B are respectively connected to the DC power source 5 via a variable resistor 7. The first and second high frequency switches are provided alternately to the second electrodes 3A and 3B. These first and second high-frequency switches 6A and 6B include transistors 8A and 9A and 8B and 9B, respectively.
And B. 10 is the first and second electrodes 3
A capacitor connected between A and 3B.

Reference numeral 11 denotes the first and second high frequency switches 6A,
6B is a high-frequency switching command circuit composed of a flip-flop circuit which gives a high-frequency switching command via resistors 12A and 12B, and 13 is a high-frequency switching command circuit 11 having a frequency of 30 kHz to 50 kHz.
It is a high frequency oscillator that gives a high frequency signal of kHz.

Next, a method of treating an organic compound in a gas by using such an apparatus will be described. First and second electrodes 3A, 3B in the tubular body 1 through which gas 2 such as exhaust gas from a factory passes
30V to 50kHz at a voltage of 50V to 3000V
The high-frequency alternating current of the first and second high-frequency switches 6A, 6
The effect of B is applied alternately. Such a high-frequency alternating current supplies a high-frequency signal from the high-frequency oscillator 13 to the high-frequency switching command circuit 11, and a high-frequency switching command from the high-frequency switching command circuit 11 to the first and second high-frequency switches 6A and 6B. It is formed by turning on and off the first and second high frequency switches 6A and 6B at a high cycle, and alternately applying the output from the DC power source 5 to the first and second electrodes 3A and 3B.

At this time, the AC voltage appearing between the first and second electrodes 3A and 3B is shown in FIG. The peak value of these AC voltages is determined by the variable resistor 6.

When high-frequency alternating current is applied to the first and second electrodes 3A and 3B in this manner, the first and second electrodes 3A and 3B
Between the B and the third electrode 3C, a direct current is passed through the water in the gas 2 to generate a direct current from the first electrode 3A to the third electrode 3C,
Flow alternately from the electrode 3B to the third electrode 3C.

When the gas 2 to be treated does not contain water, water vapor is supplied or water is sprayed to contain the water.

As a result, the water in the gas 2 is electrolyzed,
Electrons flow to the ground side through the third electrode 3C, the oxidation-reduction potential of water decreases, and the reduction potential is reached.

In particular, in this case, the first and second electrodes 3A,
Since an electrode made of a metal that lowers the redox potential is used as 3B, the redox potential of water is, for example, +3.
It can be significantly reduced from 00 mV.

For example, an electrode made of zinc is -500 m.
V to −600 mV, an electrode made of lithium can be lowered to about −2500 mV, and an electrode made of aluminum can be made −100.
It can be reduced to about 0 mV. That is, the electrodes 3A and 3B made of a metal that lowers the redox potential
Dissolves in water during the electrolysis of water and acts to lower the redox potential.

When the redox potential of the water in the gas 2 is lowered in this way, an electronic reaction (for example, an ionic bond, a covalent bond, etc.) or a chemical reaction occurs with respect to the organic compound in the gas 2 and the organic compound Aggregate and sink. In addition, active oxygen is generated by electrolysis of water and reacts with an organic compound in the gas 2, chemical combustion or the like occurs, and the free radical becomes a chemically stable radical. As a result, the organic compound in the gas 2 is recovered or rendered harmless.

If the tubular body 1 is made of metal and is grounded as shown in FIG. 3, the tubular body 1 can also be used as the third electrode 3C.

FIG. 4 shows a second embodiment of the apparatus for treating organic compounds in a gas used in the present invention. In addition,
The parts corresponding to those in the first embodiment described above are designated by the same reference numerals.

In the figure, 3D is a fourth electrode,
The first to third electrodes 3A to 3C are arranged to face each other in the tubular body 1 as shown in the drawing. The third and fourth electrodes 3
C and 3D may be arranged in the center of the tubular body 1 as shown by the phantom line in FIG. The first and second electrodes 3A and 3B are formed of a metal that lowers the redox potential as in the first embodiment. 14A and 14B are third and fourth electrodes 3C and 3D
Low-frequency switch for alternately grounding at low cycle, 15
Divides the high frequency signal of 30 kHz to 50 kHz of the high frequency oscillator 13 into, for example, 1/2 ¹⁴ , and issues a low frequency switching command to the low frequency switches 14A and 14B via the resistors 16A and 16B.
It is a low frequency switching command circuit given to B. 17A, 17B
Is a low-frequency switch 14A, 14B composed of transistors
Is a resistor for connecting the collector of the above to the positive side of the DC power supply and holding the third or fourth electrode 3C, 3D at a positive potential when the switch is turned off.

In this embodiment, the first and second electrodes 3A, 3
Similarly to the first embodiment, a high frequency alternating current of 30 kHz to 50 kHz at a voltage of 50 V to 3000 V is alternately applied to B by the action of the first and second high frequency switches 6A and 6B.

On the other hand, the low-frequency switches 14A and 14B are supplied with a low-frequency signal by the low-frequency switching command circuit 15, and the low-frequency switches 14A and 14B are alternately turned on at a low cycle, whereby the third, fourth and third switches are turned on. The electrodes 3C and 3D are alternately grounded. The turned-off electrode 3C or 3D is held at a positive potential via the resistor 17A or 17B.

By doing so, the direct current is passed through the water in the gas 2 from the electrodes 3A, 3B between the first and second electrodes to which the high-frequency alternating current is alternately applied, and the direct current is changed to the third or fourth electrode 3C, 3D.
Will flow alternately.

When the non-grounded third or fourth electrode 3C, 3D is set to a positive potential, it is possible to prevent dust such as calcium from adhering to the electrode surface and facilitate maintenance.

In each of the above embodiments, the treatment of exhaust gas from a factory or the like has been described, but the present invention can also treat exhaust gas containing nitrogen oxides discharged from a muffler of an automobile in the same manner. In this case, the pipe body 1 serves as an automobile muffler.

In order to perform the treatment more reliably, the electrodes 3A to 3C or 3A to 3D may be arranged in a plurality of stages in the longitudinal direction of the flue 1a.

When the voltage applied between the first and second electrodes 3A and 3B is a rectangular wave, the redox potential can be lowered more efficiently.

[0034]

As described above, according to the method for treating an organic compound in a gas according to the present invention, the following effects can be obtained.

According to the first aspect of the present invention, since alternating current is applied between the first and second electrodes and the third electrode is grounded, moisture in the gas is transferred from the first and second electrodes to the third electrode. Then, a direct current flows, the water is electrolyzed, and the redox potential of the water can be lowered to the reduction potential.

When the redox potential of water in the gas is lowered in this way, an electronic reaction or a chemical reaction occurs with respect to the organic compound in the gas, and the organic compound can be coagulated and precipitated. In addition, active oxygen is generated by electrolysis of water, reacts with an organic compound in a gas, and chemical combustion or the like is generated, so that free radicals can be chemically stable radicals. Therefore, the organic compound in the gas can be recovered or made harmless.

Further, in this method, since no chemicals or the like are used, it is possible to process the gas at low cost.

According to the second aspect of the present invention, there is an advantage that the object can be prevented from adhering to not only the first and second electrodes but also the third and fourth electrodes, which facilitates maintenance.

[Brief description of drawings]

FIG. 1 is an electric circuit diagram of an apparatus for treating an organic compound in a gas according to a first embodiment of the present invention.

FIG. 2 is a waveform diagram of high frequency alternating current applied to the first and second electrodes in the first embodiment.

FIG. 3 is a cross-sectional view showing a modified example of the tube body and the electrodes used in FIG.

FIG. 4 is an electric circuit diagram of an apparatus for treating an organic compound in a gas according to a second embodiment of the present invention.

[Explanation of symbols]

 1 Tube 1a Flue 2 Gas 3A-3D 1st-4th electrode 5 DC power supply 6A, 6B 1st, 2nd high frequency switch 10 Capacitor 11 High frequency switching command circuit 13 High frequency oscillator 14A, 14B Low frequency switch 15 Low Frequency switching command circuit 17A, 17B resistance

Claims (3)

[Claims] 1. A first electrode, a second electrode, and a third electrode are arranged, an alternating current is applied between the first electrode and the second electrode, the third electrode is grounded, and a treatment containing water is provided. The gas is the first, second,
A direct current is passed from the first and second electrodes through the water in the gas to the third electrode so that the water is electrolyzed and the redox potential of the water is changed. A method for treating an organic compound in a gas, which comprises lowering and treating the obtained organic compound in the gas with water having a reduction potential and active oxygen. 2. A first electrode, a second electrode, a third electrode, and a fourth electrode are arranged, an alternating current is applied between the first electrode and the second electrode, and the third electrode and the fourth electrode are alternated at a low cycle. The electrode for non-grounding is set to a positive potential, and a processing gas containing water is passed so as to touch the first, second, third and fourth electrodes, A DC current is passed through the water in the gas from the second electrode to the third or fourth electrode grounded, and the water is electrolyzed to reduce the oxidation-reduction potential of the water. A method for treating an organic compound in a gas, comprising treating the organic compound in the gas with active oxygen. 3. The method for treating an organic compound in a gas according to claim 1, wherein an electrode made of a metal that lowers a redox potential is used as the first and second electrodes.