Nitrogen pentoxide generating device and method for generating dinitrogen pentoxide

Abstract

[Problem] To provide a dinitrogen pentoxide generating device and a dinitrogen pentoxide generating method capable of using highly safe raw materials and capable of producing dinitrogen pentoxide relatively easily. [Solution] An NOx generating unit 13 is provided to be able to make plasma using a gas including nitrogen and oxygen as a raw material gas to generate nitrogen oxides. An ozone generating unit 14 is provided to be able to make plasma using a gas including nitrogen and oxygen or a gas from after making plasma in the NOx generating unit 13 as a raw material gas to generate ozone. A mixing unit 15 is provided to be able to generate dinitrogen pentoxide by holding the nitrogen oxides generated by the NOx generating unit 13 and the ozone generated by the ozone generating unit 14 in the same space for a predetermined time.

Description

[Technical Field]

[0001] The present invention relates to a dinitrogen pentoxide generating device and a dinitrogen pentoxide generating method. [Background technology]

[0002] Dinitrogen pentoxide (N2O5) in the gas phase is a substance that is difficult to preserve due to thermal decomposition, etc., but when it dissolves in liquid, it turns into an intermediate (NO2 + ) that induces unique chemical reactions, resulting in effects such as sterilization, disinfection, and cell activation, and is therefore expected to be applied not only in the field of chemistry but also in the fields of environment, agriculture, and medicine.

[0003] Conventionally, the method for producing dinitrogen pentoxide is to mix concentrated sulfuric acid and concentrated nitric acid (pH<1) to produce diphosphorus pentoxide (PO 10 ) to produce dinitrogen pentoxide (see, for example, Non-Patent Document 1), or + BF4 - ],(NO2 + CF3SO3 - )) to generate dinitrogen pentoxide (see, for example, Non-Patent Document 1), and a method of generating dinitrogen pentoxide by mixing ozone gas with high-concentration nitrogen dioxide gas (see, for example, Non-Patent Document 2). [Prior art documents] [Non-patent literature]

[0004] [Non-Patent Document 1] E. Wiberg, N. Wiberg and A. Holleman, “Inorganic Chemistry”, Berlin: Academic Press, 2001 [Non-patent document 2] CH Wu, ED Morris, and H. Niki, “The Reaction of Nitrogen Dioxide with Ozone”, J. Phys. Chem., 1973, 77, p. 2507 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the method described in Non-Patent Document 1, which uses concentrated sulfuric acid and concentrated nitric acid as raw materials, has the problem of being highly dangerous because these raw materials are strong acids and a violent exothermic reaction occurs when dinitrogen pentoxide is produced. Furthermore, the method described in Non-Patent Document 1, which involves dissolving salt at room temperature, has the problem of making it extremely difficult to produce the raw salt because the raw salt is highly hygroscopic, necessitating a high vacuum state. The method described in Non-Patent Document 3 has the problem of being highly dangerous when handling the raw material, because the highly concentrated nitrogen dioxide is a toxic substance. Furthermore, when synthesizing dinitrogen pentoxide, it is frozen with liquid nitrogen and separated as a solid, which simultaneously produces solid ozone, which may be explosive, and therefore has the problem of being highly dangerous.

[0006] The present invention has been made in light of these problems, and aims to provide a dinitrogen pentoxide generator and a dinitrogen pentoxide generation method that can use highly safe raw materials and can relatively easily produce dinitrogen pentoxide. [Means for solving the problem]

[0007] In order to achieve the above object, the dinitrogen pentoxide generator of the present invention is characterized by having: a NOx generation unit configured to generate plasma using a gas containing nitrogen and oxygen as a raw material gas to generate nitrogen oxides (NOx); an ozone generation unit configured to generate plasma using a gas containing nitrogen and oxygen or the gas after plasma generation in the NOx generation unit as a raw material gas to generate ozone; and a mixing unit configured to generate dinitrogen pentoxide by maintaining the nitrogen oxides generated in the NOx generation unit and the ozone generated in the ozone generation unit in the same space for a predetermined time.

[0008] The dinitrogen pentoxide production method according to the present invention is characterized by comprising: a NOx production process in which nitrogen oxides are produced by generating plasma using a gas containing nitrogen and oxygen as a raw material gas; an ozone production process in which ozone is produced by generating plasma using a gas containing nitrogen and oxygen or the gas obtained after plasma generation in the NOx production process as a raw material gas; and a mixing process in which the nitrogen oxides produced in the NOx production process and the ozone produced in the ozone production process are held in the same space for a predetermined time to produce dinitrogen pentoxide.

[0009] The dinitrogen pentoxide generating method of the present invention is preferably implemented by the dinitrogen pentoxide generating device of the present invention. The dinitrogen pentoxide generating device and dinitrogen pentoxide generating method of the present invention can use a highly safe gas containing nitrogen and oxygen as a raw material. For example, air can be used as the gas containing nitrogen and oxygen, and plasma generated by atmospheric discharge can be used. Furthermore, nitrogen oxides and ozone generated by plasma can be kept in the same space for a predetermined time, thereby reacting them to produce dinitrogen pentoxide. In this way, the dinitrogen pentoxide generating device and dinitrogen pentoxide generating method of the present invention can relatively easily produce dinitrogen pentoxide using a highly safe raw material and plasma.

[0010] The dinitrogen pentoxide generator and method of the present invention are configured such that, when a gas containing nitrogen and oxygen is used as a source gas for generating ozone, the separately generated nitrogen oxides and ozone are collected in the same space and held there for a predetermined period of time. Furthermore, when a gas obtained by generating nitrogen oxides using plasma is used as a source gas for generating ozone, the gas obtained by generating ozone contains both nitrogen oxides and ozone, so the gas obtained by generating ozone is placed in a single space and held there for a predetermined period of time.

[0011] In the dinitrogen pentoxide generating device and method according to the present invention, nitrogen oxides generated by plasma using a gas containing nitrogen and oxygen as a raw material gas include, for example, NO, NO2, and N2O.

[0012] In the nitrogen pentoxide generating device according to the present invention, the NOx generating unit generates plasma at a temperature of 200°C or higher, and the ozone Generate Preferably, the nitrogen pentoxide generating unit generates plasma at a temperature of 50° C. or less, and the mixing unit holds the nitrogen oxides and the ozone at a temperature of 100° C. or less. In the dinitrogen pentoxide generating method according to the present invention, the NOx generating step generates plasma at a temperature of 200° C. or more, and the ozone Generate Preferably, the step generates plasma at a temperature of 50°C or less, and the mixing step maintains nitrogen oxides and ozone at a temperature of 100°C or less. In this case, by generating plasma at a temperature of 200°C or more, nitrogen in the source gas can be efficiently dissociated, thereby increasing the efficiency of nitrogen oxide production by plasma. Furthermore, by generating plasma at a temperature of 50°C or less, the efficiency of ozone production by plasma can be increased. These factors also increase the efficiency of dinitrogen pentoxide production. Furthermore, by maintaining nitrogen oxides and ozone at a temperature of 100°C or less, the efficiency of dinitrogen pentoxide production can be further increased.

[0013] The dinitrogen pentoxide generator of the present invention reduces the humidity of a gas containing nitrogen and oxygen to 1×10 15cm -3 The method for generating dinitrogen pentoxide according to the present invention preferably includes a raw material gas generating unit configured to adjust the humidity of a gas containing nitrogen and oxygen to 1×10 or less (approximately 40 ppm) and supply the gas to the NOx generating unit and the ozone generating unit, or to the NOx generating unit. 15 cm -3 It is preferable to adjust the concentration of dinitrogen pentoxide to be equal to or less than about 40 ppm in the NOx generation step and the ozone generation step, or to have a step of generating a raw material gas to be supplied to the NOx generation step. In this case, dinitrogen pentoxide can be produced at a high concentration.

[0014] In the dinitrogen pentoxide generator of the present invention, the mixing section may have a tube, and the nitrogen oxide-containing gas produced in the NOx generation section and the ozone-containing gas produced in the ozone generation section may be introduced through an opening at one end of the tube and discharged from an opening at the other end of the tube after the predetermined time has elapsed. In the dinitrogen pentoxide generation method of the present invention, in the mixing step, the nitrogen oxide-containing gas produced in the NOx generation step and the ozone-containing gas produced in the ozone generation step may be introduced through an opening at one end of the tube and discharged from an opening at the other end of the tube after the predetermined time has elapsed. In this case, the nitrogen oxide and ozone can react inside the tube, and the dinitrogen pentoxide produced by the reaction can be discharged from the opening at the other end of the tube. The tube preferably has a length and diameter that allow the predetermined time for the nitrogen oxide and ozone introduced through the opening at one end to react while passing through the tube.

[0015] The dinitrogen pentoxide generator according to the present invention is preferably configured so that the dinitrogen pentoxide generated in the mixing section can be discharged into the liquid. The dinitrogen pentoxide generating method according to the present invention is preferably configured so that the dinitrogen pentoxide generated in the mixing step can be discharged into the liquid. In this case, when dinitrogen pentoxide dissolves in the liquid, it generates a highly reactive intermediate (NO2 + ) and induce specific chemical reactions, such as the production of bactericidal active species such as HOONO and HOONO2, and NO3 -This allows the liquid from which dinitrogen pentoxide is emitted to be used for sterilization, disinfection, cell activation, etc.

[0016] In the dinitrogen pentoxide generating device and method according to the present invention, the predetermined time is preferably 0.5 to 600 seconds, and more preferably 20 seconds or more, in which case dinitrogen pentoxide can be produced particularly efficiently and selectively. [Effects of the Invention]

[0017] According to the present invention, it is possible to provide a dinitrogen pentoxide generator and a dinitrogen pentoxide generating method that can use highly safe raw materials and can relatively easily produce dinitrogen pentoxide. [Brief explanation of the drawings]

[0018] [Figure 1] 1 is a block diagram showing a dinitrogen pentoxide generating device according to an embodiment of the present invention. [Figure 2] 2A and 2B are front views showing the NOx generation section and the ozone generation section of the dinitrogen pentoxide generation device shown in FIG. 1. [Figure 3] FIG. 10 is a block diagram showing a modified example of the dinitrogen pentoxide generating device according to the embodiment of the present invention. [Figure 4] 2 is a graph showing the number density of each active species contained in the gas produced by the dinitrogen pentoxide generator shown in FIG. 1. [Figure 5] 2 is an IR spectrum of the gas produced by the dinitrogen pentoxide generator shown in FIG. 1. [Figure 6] 2 is a graph showing the relationship between the time tr and the number density (Density) of each active species when the time tr for the reaction of nitrogen oxides with ozone is changed by changing the length and inner diameter of the tube of the dinitrogen pentoxide generator shown in FIG. 1. DETAILED DESCRIPTION OF THE INVENTION

[0019] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. 1 to 6 show a dinitrogen pentoxide generating apparatus and a dinitrogen pentoxide generating method according to an embodiment of the present invention. As shown in FIGS. 1 and 2, the dinitrogen pentoxide generator 10 includes a raw material gas generator 11, a pair of flow rate controllers 12a and 12b, a NOx generator 13, an ozone generator 14, and a mixer 15.

[0020] As shown in Fig. 1, the raw material gas generating unit 11 is configured to be able to introduce a gas containing nitrogen and oxygen, dehydrate the gas, and adjust the humidity. The raw material gas generating unit 11 is configured to be able to supply the humidity-adjusted gas as a raw material gas to the NOx generating unit 13 and the ozone generating unit 14 via the flow rate control units 12a and 12b. In a specific example shown in Fig. 1, the raw material gas generating unit 11 adjusts the humidity of the introduced gas to 1 x 10 15 cm -3 The raw material gas generator 11 is connected to a cylinder 11a that stores a gas containing nitrogen and oxygen, and the gas is introduced from the cylinder 11a. The gas stored in the cylinder 11a is air, but any gas other than air may be used as long as it contains nitrogen and oxygen. When air is used, the cylinder 11a may not be used and surrounding air may be collected and used.

[0021] One flow rate control unit 12a is connected to the raw material gas generation unit 11 and the NOx generation unit 13, and the other flow rate control unit 12b is connected to the raw material gas generation unit 11 and the ozone generation unit 14. Each of the flow rate control units 12a and 12b is configured to introduce the raw material gas whose humidity has been adjusted in the raw material gas generation unit 11, adjust the flow rate and flow velocity, and supply the gas to the NOx generation unit 13 or the ozone generation unit 14.

[0022] As shown in FIG. 2(a), the NOx generation unit 13 includes a reaction vessel 21, a gas supply unit 22, a gas discharge unit 23, a pair of electrodes 24a, 24b, and a power supply unit (not shown). The reaction vessel 21 includes an elongated cylindrical outer cylinder 21a, an elongated cylindrical inner cylinder 21b inserted inside the outer cylinder 21a with a gap between them, and a cap 21c that closes the opening of the outer cylinder 21a at one end. The outer cylinder 21a and the inner cylinder 21b are made of insulators. The inner cylinder 21b is disposed at one end of the reaction vessel 21 with a gap between them and the cap 21c. This allows the space inside the inner cylinder 21b to communicate with the space between the outer cylinder 21a and the inner cylinder 21b at one end of the reaction vessel 21.

[0023] The gas supply unit 22 is connected to one of the flow rate control units 12a and is provided at the other end of the reaction vessel 21 so as to close the opening of the outer cylinder 21a. The gas supply unit 22 is configured to introduce the raw material gas supplied from one of the flow rate control units 12a into the space between the outer cylinder 21a and the inner cylinder 21b. The gas discharge unit 23 is connected to the mixing unit 15 and is provided at the other end of the reaction vessel 21 so as to close the opening of the inner cylinder 21b. The gas discharge unit 23 is configured to be able to discharge gas from the space inside the inner cylinder 21b and supply it to the mixing unit 15. As a result, in the NOx generation section 13, the raw material gas introduced into the space between the outer tube 21a and the inner tube 21b by the gas supply section 22 flows within that space from the other end to one end of the reaction vessel 21, enters the inside of the inner tube 21b at one end of the reaction vessel 21, and further flows inside the inner tube 21b from one end to the other end of the reaction vessel 21, and is discharged from the gas discharge section 23.

[0024] One electrode 24a is inserted into the inner cylinder 21b and extends along the length of the inner cylinder 21b from one end to the other end of the reaction vessel 21. The other electrode 24b is tubular and made of a stainless steel pipe or the like. The other electrode 24b is attached to the inside of the outer cylinder 21a at one end of the reaction vessel 21 over a predetermined range (hereinafter referred to as the "plasma generating unit 25") along the length of the reaction vessel 21 so as to face the one electrode 24a. The other electrode 24b is also grounded. A power supply is connected to the one electrode 24a, and is capable of applying a voltage between the electrodes 24a and 24b. In the specific example shown in FIG. 2(a), the power supply is configured to apply a voltage of up to 50 W between the electrodes 24a and 24b. The power supply is an AC power supply, but may be a DC power supply or a pulse power supply.

[0025] The NOx generation unit 13 generates plasma in the plasma generation unit 25 by applying a voltage between the electrodes 24a, 24b from the power supply unit while supplying raw material gas from one flow rate control unit 12a to the inside of the reaction vessel 21 via the gas supply unit 22. By adjusting the input power, plasma can be generated at temperatures of 200°C or higher, producing nitrogen oxides such as NO, NO2, and NO2O. The NOx generation unit 13 also exchanges heat between the gas after plasma generation, which flows from the plasma generation unit 25 toward the gas discharge unit 23 inside the inner tube 21b, and the raw material gas, which flows through the space between the outer tube 21a and the inner tube 21b toward the plasma generation unit 25, in the range from the other end of the reaction vessel 21 to the plasma generation unit (hereinafter referred to as the "heat exchange unit 26"). This allows the raw material gas to be heated and the gas after plasma generation to be cooled. This increases the temperature of the plasma generation unit 25 as much as possible and decreases the temperature of the gas discharged from the gas discharge unit 23 as much as possible.

[0026] As shown in FIG. 2(b), the ozone generation unit 14 includes a reaction vessel 31, a gas supply unit 32, a gas exhaust unit 33, a pair of electrodes 34a and 34b, and a power supply unit (not shown). The reaction vessel 31 is made of an insulator and has a long, thin cylindrical shape. The gas supply unit 32 is connected to the other flow rate control unit 12b and is provided to close an opening on one end of the reaction vessel 31. The gas supply unit 32 is configured to introduce the raw material gas supplied from the other flow rate control unit 12b into the reaction vessel 31. The gas exhaust unit 33 is connected to the mixer 15 and is provided to close an opening on the other end of the reaction vessel 31. The gas exhaust unit 33 is configured to exhaust gas from the internal space of the reaction vessel 31 and supply it to the mixer 15.

[0027] One electrode 34a is inserted into the reaction vessel 31 and extends along the length of the reaction vessel 31 from one end to the other. The other electrode 34b is made of copper foil or the like and is in the form of a thin sheet. The other electrode 34b is attached to the outer surface of the reaction vessel 31 by wrapping it around the entire length of the reaction vessel 31 from one end to the other (hereinafter referred to as the "plasma generating unit 35") so as to face the one electrode 34a. The other electrode 34b is also grounded. A power supply is connected to the one electrode 34a, and is capable of applying a voltage between the electrodes 34a and 34b. In the specific example shown in FIG. 2(b), the power supply is configured to apply a voltage between the electrodes 34a and 34b with as little power as possible, approximately 3 W. The power supply is an AC power supply, but may be a DC power supply or a pulse power supply.

[0028] In the ozone generation unit 14, while the raw material gas is being supplied from the other flow rate control unit 12b via the gas supply unit 32 into the reaction vessel 31, a voltage is applied between the electrodes 34a, 34b by the power supply unit, thereby generating plasma in the plasma generation unit 35. At this time, by adjusting the input power, plasma can be generated at a temperature of 50°C or less, and ozone can be generated.

[0029] As shown in FIG. 1 , the mixer 15 has a long, thin tube 41 and an orifice 42. One end of the tube 41 is connected to the gas discharge section 23 of the NOx generator 13 and the gas discharge section 33 of the ozone generator 14, and the nitrogen oxide-containing gas generated in the NOx generator 13 and the ozone-containing gas generated in the ozone generator 14 are introduced into the tube 41 and discharged from the other end. The tube 41 has a length and an inner diameter sufficient to ensure time for the introduced nitrogen oxide and ozone to react with each other to produce dinitrogen pentoxide while passing through the tube 41. The orifice 42 is attached to the other end of the tube 41. Note that the mixer 15 does not necessarily require the orifice 42.

[0030] Mixing section 15 is capable of discharging dinitrogen pentoxide generated inside tube 41 through orifice 42. Mixing section 15 is also configured to be able to discharge the generated dinitrogen pentoxide into the liquid. In a specific example shown in FIG. 1, tube 41 has a length of 5 m to 50 m and an inner diameter of 4 mm to 10 mm to ensure a time of 10 to 100 seconds for generating dinitrogen pentoxide. Tube 41 is also configured to allow nitrogen oxides and ozone to pass through its interior at a temperature of 100°C or less. Mixing section 15 may be configured in any manner as long as it is able to ensure the time required for generating dinitrogen pentoxide; this time may be ensured by pressurizing or cooling the nitrogen oxide-containing gas and the ozone-containing gas.

[0031] The dinitrogen pentoxide generating method according to the embodiment of the present invention can be suitably implemented by the dinitrogen pentoxide generating apparatus 10. The dinitrogen pentoxide generating method according to the embodiment of the present invention uses a gas containing nitrogen and oxygen as a raw material gas, generates plasma in the NOx generating unit 13 to generate nitrogen oxides, generates plasma in the ozone generating unit 14 to generate ozone, and reacts the generated nitrogen oxides and ozone for a predetermined time inside the tube 41 of the mixing unit 15, thereby generating dinitrogen pentoxide.

[0032] The dinitrogen pentoxide generator 10 and dinitrogen pentoxide generating method of the present invention can use a highly safe gas containing nitrogen and oxygen, such as air, as a raw material. Furthermore, by maintaining the nitrogen oxides and ozone generated by plasma in the same space inside the tube 41 for a predetermined time, the nitrogen oxides and ozone can be sufficiently reacted to produce dinitrogen pentoxide. In this way, the dinitrogen pentoxide generator 10 and dinitrogen pentoxide generating method of the present invention can relatively easily produce dinitrogen pentoxide by using a highly safe raw material and plasma.

[0033] The dinitrogen pentoxide generator 10 and dinitrogen pentoxide generation method according to the present invention generate plasma at a temperature of 200°C or higher in the NOx generation unit 13, thereby efficiently dissociating nitrogen in the source gas and increasing the efficiency of nitrogen oxide generation by plasma. Furthermore, generating plasma at a temperature of 50°C or lower in the ozone generation unit 14 increases the efficiency of ozone generation by plasma. Furthermore, by lengthening the other electrode 34b of the ozone generation unit 14 and reducing the power density while maintaining a constant input power, the temperature rise in the plasma generation unit 35 can be suppressed, further increasing the efficiency of ozone generation. Furthermore, the heat exchanger 26 of the NOx generation unit 13 can maximize the temperature of the plasma generation unit 25 of the NOx generation unit 13 while simultaneously minimizing the temperature of the gas discharged from the gas discharge unit 23, further increasing the efficiency of nitrogen oxide generation. These features also increase the efficiency of dinitrogen pentoxide generation.

[0034] Furthermore, in the dinitrogen pentoxide generator 10 and the dinitrogen pentoxide generating method according to the embodiment of the present invention, the humidity of the source gas is adjusted to 1×10 15 cm -3 By adjusting the concentration to below about 40 ppm, it is possible to produce nitrogen pentoxide at a high concentration.

[0035] In the dinitrogen pentoxide generator 10 and dinitrogen pentoxide generation method according to the embodiment of the present invention, the heat exchanger 26 of the NOx generation unit 13 can lower the temperature of the gas after plasma generation, thereby suppressing temperature increases in the gas supply unit 22 and gas discharge unit 23 of the NOx generation unit 13 and the gas supply unit 32 of the ozone generation unit 14. Furthermore, by keeping the plasma generation temperature in the ozone generation unit 14 at 50°C or below, temperature increases in the gas discharge unit 33 of the ozone generation unit 14 can be suppressed. This improves the durability of the gas supply unit 22 and gas discharge unit 23 of the NOx generation unit 13 and the gas supply unit 32 and gas discharge unit 33 of the ozone generation unit 14. In particular, by maintaining the temperatures of these components at 150°C or below, durability can be dramatically improved. Furthermore, because the gas temperatures in the gas discharge unit 23 of the NOx generation unit 13 and the gas discharge unit 33 of the ozone generation unit 14 are low, the gas temperature in the mixing unit 15 can be lowered, enabling efficient production of dinitrogen pentoxide.

[0036] The dinitrogen pentoxide generator 10 and the dinitrogen pentoxide generating method according to the embodiment of the present invention are configured such that the dinitrogen pentoxide generated in the mixing section 15 is discharged into a liquid, and when the dinitrogen pentoxide dissolves in the liquid, it turns into an intermediate (NO2 + ) and induce specific chemical reactions, such as the production of bactericidal active species such as HOONO and HOONO2, and NO3 - This allows the liquid from which dinitrogen pentoxide is emitted to be used for sterilization, disinfection, cell activation, etc.

[0037] As shown in FIG. 3, the dinitrogen pentoxide generator 10 may have the ozone generator 14 located between the NOx generator 13 and the mixer 15. That is, the gas supply unit 32 of the ozone generator 14 may be connected to the gas exhaust unit 23 of the NOx generator 13, and the ozone generator 14 may be configured to generate plasma and generate ozone using the gas resulting from plasma generation in the NOx generator 13 as a raw material gas. In this case, the gas resulting from ozone generation contains ozone and the nitrogen oxides generated in the NOx generator 13. Therefore, the gas resulting from ozone generation can be generated by placing the gas resulting from ozone generation inside the tube 41 and holding it there for a predetermined period of time. Furthermore, since only one flow rate controller 12a is required, the manufacturing and operating costs of the device can be reduced. [Example]

[0038] A dinitrogen pentoxide production experiment was conducted using the dinitrogen pentoxide generator 10 shown in Figure 1. In the experiment, air was used as the raw material gas, and the raw material gas was supplied to the NOx generation unit 13 at a flow rate of 1 slm by one flow rate control unit 12a, and to the ozone generation unit 14 at a flow rate of 1 slm by the other flow rate control unit 12b. The inner diameter and length of the tube 41 in the mixing unit 15 were set to 10 mm and 10 m, respectively. As a result, the time required for the nitrogen oxide-containing gas and the ozone-containing gas to pass through the inside of the tube 41, i.e., the time required for the nitrogen oxides and ozone to react, was 24 seconds.

[0039] The infrared absorption spectrum (IR spectrum) of the gas discharged from the orifice 42 was obtained by infrared spectroscopy using a Fourier transform infrared spectrometer (FT-IR) and the number density (density) of each active species contained in the gas was determined. The number density and IR spectrum of each active species obtained are shown in Figures 4 and 5, respectively. As shown in Figures 4 and 5, it was confirmed that the gas discharged from the mixing section 15 contained more dinitrogen pentoxide (NO) than the nitrogen oxides (NO, NO, NO, HNO, and HNO) generated in the NOx generation section 13 or the ozone (O) generated in the ozone generation section 14. This is thought to be because the nitrogen oxides and ozone reacted sufficiently inside the tube 41 of the mixing section 15 to generate dinitrogen pentoxide.

[0040] Next, the length and inner diameter of the tube 41 of the mixing section 15 are changed to measure the time it takes for the nitrogen oxides to pass through the tube 41, i.e., the time it takes for the nitrogen oxides to react with the ozone, t r The number density of each active species contained in the gas discharged from the orifice 42 was determined using a Fourier transform infrared spectrometer while changing the reaction time t r It was confirmed that the concentration of ozone (O3) and NO2 increased with the reaction time t r It was confirmed that the reaction time t r Even after the reaction time t r It was observed that the time increased slightly until it reached about 30 seconds.

[0041] From the results shown in Figure 6, the reaction time t r It can be said that dinitrogen pentoxide can be produced efficiently by configuring the mixing section 15 so that the reaction time is 20 seconds or more. It is also thought that dinitrogen pentoxide is produced mainly by the reaction of NO2 with ozone. [Explanation of symbols]

[0042] 10. Nitrogen pentoxide generator 11 Raw material gas generation section 11a Cylinder 12a,12b Flow control section 13 NOx generation section 21 Reaction vessel 21a Outer cylinder 21b Inner cylinder 21c Cap 22 Gas supply section 23 Gas exhaust section 24a,24b electrode 25 Plasma generation unit 26 Heat exchange section 14 Ozone generation unit 31 Reaction vessel 32 Gas supply unit 33 Gas exhaust section 34a,34b electrode 35 Plasma generation unit 15 Mixing section 41 tubes 42 Orifice

Claims

1. a NOx generating unit configured to generate plasma using a gas containing nitrogen and oxygen as a raw material gas to generate nitrogen oxides; an ozone generating unit that is capable of generating plasma and generating ozone using a gas containing nitrogen and oxygen or a gas obtained after plasma generation in the NOx generating unit as a raw material gas; a mixing section configured to be able to generate dinitrogen pentoxide by holding the nitrogen oxides generated in the NOx generating section and the ozone generated in the ozone generating section in the same space for a predetermined time; a raw material gas generating section configured to be able to supply a gas containing nitrogen and oxygen, which is dehydrated to adjust the humidity, as a raw material gas to the NOx generating section and the ozone generating section, or to the NOx generating section when the ozone generating section uses gas obtained after plasma generation in the NOx generating section as a raw material gas; A nitrogen pentoxide generating device characterized by having:

2. a NOx generating unit configured to generate plasma using a gas containing nitrogen and oxygen as a raw material gas to generate nitrogen oxides; an ozone generating unit that is capable of generating plasma and generating ozone using a gas containing nitrogen and oxygen or a gas obtained after plasma generation in the NOx generating unit as a raw material gas; a mixing section that is provided so as to be able to generate dinitrogen pentoxide by holding the nitrogen oxides generated in the NOx generating section and the ozone generated in the ozone generating section in the same space for a predetermined time, The mixing section has a tube, and is configured so that the gas containing nitrogen oxides generated in the NOx generating section and the gas containing ozone generated in the ozone generating section can be introduced from an opening on one end side of the tube, and can be discharged from an opening on the other end side of the tube after the predetermined time has elapsed. A nitrogen pentoxide generator characterized by:

3. The NOx generating unit generates plasma at a temperature of 200°C or higher, The ozone generating unit generates plasma at a temperature of 50°C or less, The mixing section is configured to maintain the nitrogen oxides and the ozone at a temperature of 100°C or less.

3. The dinitrogen pentoxide generating device according to claim 1 or 2.

4. The raw material gas generating unit adjusts the humidity of the gas containing nitrogen and oxygen to 1×10 １５ cm －３ 2. The dinitrogen pentoxide generating device according to claim 1, characterized in that it is configured so that the dinitrogen pentoxide can be adjusted to the following and supplied to the NOx generating section and the ozone generating section, or to the NOx generating section.

5. 5. The nitrogen pentoxide generating apparatus according to claim 1, 3 or 4, characterized in that the mixing section has a tube, and is configured so that the gas containing nitrogen oxides generated in the NOx generating section and the gas containing ozone generated in the ozone generating section can be introduced from an opening on one end side of the tube and discharged from an opening on the other end side of the tube after the predetermined time has elapsed.

6. 6. The dinitrogen pentoxide generator according to claim 1, wherein the dinitrogen pentoxide generated in the mixing section can be discharged into the liquid.

7. 7. The dinitrogen pentoxide generator according to claim 1, wherein the predetermined time is 20 seconds or more.

8. a NOx generation step in which a gas containing nitrogen and oxygen is used as a raw material gas to generate plasma and generate nitrogen oxides; an ozone generation process in which ozone is generated by generating plasma using a gas containing nitrogen and oxygen or the gas obtained after plasma generation in the NOx generation process as a raw material gas; a mixing step of generating dinitrogen pentoxide by holding the nitrogen oxides generated in the NOx generation step and the ozone generated in the ozone generation step in the same space for a predetermined time; a raw material gas generation step of introducing a gas containing nitrogen and oxygen, dehydrating the gas to adjust the humidity, and supplying the gas to the NOx generation step and the ozone generation step, or to the NOx generation step when the ozone generation step uses the gas obtained after plasma generation in the NOx generation step as the raw material gas; A method for producing dinitrogen pentoxide, comprising:

9. a NOx generation step in which a gas containing nitrogen and oxygen is used as a raw material gas to generate plasma and generate nitrogen oxides; an ozone generation process in which ozone is generated by generating plasma using a gas containing nitrogen and oxygen or the gas obtained after plasma generation in the NOx generation process as a raw material gas; a mixing step of generating dinitrogen pentoxide by holding the nitrogen oxides generated in the NOx generation step and the ozone generated in the ozone generation step in the same space for a predetermined time, The mixing step includes introducing the gas containing nitrogen oxides generated in the NOx generation step and the gas containing ozone generated in the ozone generation step from an opening on one end side of a tube, and discharging the gas from an opening on the other end side of the tube after the predetermined time has elapsed. A method for producing dinitrogen pentoxide.

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