JP3626319B2 - Reaction method and apparatus using high-temperature and high-pressure fluid - Google Patents

Description

【００２９】
ここで、ｋ＝Ｃｐ／Ｃｖ：比熱比である。
【００３０】
上記式（１）あるいは式（２）が示す通りの温度上昇が得られるから、分解に必要な活性化エネルギーはさらに大きくなる。また、安定物質に変わる又は反応途中の物質は半周期で断熱膨張となるため急速冷却されることとなり、副生成物の発生も少なくなる。
【００３１】
ところで、図５に示す模式的Ｐ−Ｔ線図によれば、超音波照射された過熱蒸気は、点Ａの状態から点Ｃの状態を経て点Ｂの状態へと変化する。つまり、Ａ→Ｃ→Ｂの過程での断熱圧縮と、Ｂ→Ｃ→Ａの断熱膨張とを繰り返すこととなる。
【００３２】
この時における化学反応の自由エネルギーＧのプロフィールを見ると、図６に示すように、点Ｄの状態から点Ｅの状態を経て点Ｆの状態になり化学反応が終了する。ここで、Ｇ′が活性化エネルギーを示し、Ｇ_２−Ｇ_１＝ΔＧが自由エネルギー変化で負になる方向に進む。
【００３３】
この活性化エネルギーＧ′は、化学反応が進むためには必ず必要であり、このエネルギーＧ′は、超臨界状態（即ち、図５の点Ｂ）でなくとも、超臨界状態に近い高温高圧状態（即ち、図５の点Ｃ）においても得られる場合がある。例えば、フロンなどは、超臨界状態に近い高温高圧状態でも十分に分解可能である。なお、クロロベンゼンなどは超臨界状態でないと分解できない。
【００３４】
上記した活性化エネルギーＧ′（換言すれば、自由エネルギーＧの増加ｄＧ）は、断熱変化では等エントロピー変化となるから、
ｄＧ＝ｄＨ−ＴｄＳ
で与えられる。
【００３５】
ここで、ｄＳ＝０であるから、ｄＧ＝ｄＨとなり、エンタルピー変化と等しくなる。
【００３６】
この時、
ΔＨ＝ｍＣｐ（Ｔ_２−Ｔ_１）＝（ｋ／ｋ−１）（ｐ_２Ｖ_２−ｐ_１Ｖ_１）
と表せ、自由エネルギーは増加する。
【００３７】
また、断熱圧縮の部分だけを考えてみると、急速な圧力増加を伴うので、温度をほぼ一定と考えれば、
Ｇ_２−Ｇ_１＝ｍＲＴｌｎ（ｐ_２／ｐ_１）
となり、自由エネルギーはやはり増加する。
【００３８】
つまり、全体として、圧縮・膨張を考えると、ΔＳ＝０であるが、反応する局部的に見ると、以上のようになり、活性化エネルギーＧ′が容易に得られるのである。
【００３９】
以上説明したように、反応装置７内の溶媒は、連続的な超臨界状態あるいは超臨界状態に近い高温高圧状態ではないが、超音波の周期で繰り返し生ずる高音圧部は超臨界状態あるいは超臨界状態に近い高温高圧状態となる。つまり、反応装置７内に超臨界流体あるいは超臨界流体に近い高温高圧流体が現出するのである。一方、被分解物質の分解は分子同士の衝突が基本であるから上記した超臨界状態あるいは超臨界状態に近い高温高圧状態の繰り返しにより溶媒分子の衝突速度がさらに加速され、その運動エネルギーは著しく大きくなり、さらに超臨界状態あるいは超臨界状態に近い高温高圧状態での活性化エネルギーも同時に得られることとなる。従って、反応装置７内における反応速度（換言すれば、分解速度）は通常の超臨界状態あるいは超臨界状態に近い高温高圧状態や過熱蒸気状態のときよりもさらに速くなるのである。
【００４０】
さらに、前記反応装置７において被分解物質の分解により生成された生成ガスは冷却装置１３に送られ、該冷却装置１３において前記生成ガスが冷却水との熱交換により冷却液化される。そして、この冷却装置１３により冷却液化された生成物（気液混合状態である）は気液分離装置１４に送られ、液体と気体とに分離される。かくして分離された気体は無害化装置１５に送られ、中和処理等により無害化された後、大気へ開放される。なお、分離された液体は廃液タンク（図示省略）に溜め込まれる。
【００４１】
次に、環境汚染物質であり難分解物質であるフロンガスを分解処理する場合を例にとって以下にその動作態様を説明する。
【００４２】
被分解物質タンク１内に液化したフロンを投入するとともに溶媒タンク２内に水を投入し、流体ポンプ３，４を駆動させることによってフロンと溶媒である水とを蒸気発生装置５に送り込んで両者を適当な比率で混合する。
【００４３】
該蒸気発生装置５は、ヒータ６によって予め加熱されており、蒸気発生装置５内において両者が蒸発して４００℃程度の過熱蒸気が生成される。なお、分解処理するために必要な過熱蒸気の温度は被分解物質によって異なるため、それぞれ被分解物質に応じて設定される。
【００４４】
上記のようにして得られた過熱蒸気は、圧力勾配により反応装置７へ移送されるが、該反応装置７は、ヒータ８の駆動によって移送されてきた過熱蒸気の温度を維持できるように過熱状態に保持されている。この反応装置７内を過熱蒸気が通過する間に所定の反応時間経過するまで保持されるが、同時に超音波発振器１２の駆動により超音波ホーン１０から所定の周波数と出力を有する超音波が反応装置７内へ照射される。すると、前述したように、溶媒の過熱蒸気における超音波の高音圧部に超臨界状態あるいは超臨界状態に近い高温高圧状態が現出することとなり、フロンの加水分解が次式により速やかに進行する。ここで、超音波の周波数としては１５ｋＨｚ〜３００ｋＨｚ程度が好ましい。
【００４５】
ＣＣｌ_２Ｆ_２＋２Ｈ_２Ｏ→ＣＯ_２＋２ＨＦ＋２ＨＣｌ
ちなみに、上記加水分解反応における反応温度および反応圧力について従来の方法と本発明方法とで比較したところ、表１の結果が得られた。
【００４６】
【表１】

【００４７】
上記結果によれば、本発明方法によれば、反応温度をあまり高くすることなく、しかも反応装置７内全体を高圧にすることなく、部分的高圧（即ち、高音圧部のみが超臨界状態あるいは超臨界状態に近い高温高圧状態）でフロンの加水分解が速やかに進行することがわかる。
【００４８】
上記のようにして反応装置７においてフロンの加水分解により生成された生成ガスは、冷却装置１３へ送られ、冷却液化される。該冷却装置１３の温度は生成ガスを液化できる程度であればよく、フロン分解の場合、生成ガス中の弗化水素ＨＦが液化する温度である約１８℃とされる。
【００４９】
上記のようにして液化された生成物は、気液分離装置１４において気体と液体に分離され、気体は無害化装置１５において無害化された後大気中ほ放出される。一方、分離された液体は、廃液タンク（図示省略）に溜め込まれる。このように液化することにより副生成物の発生が防止される。また、液化することにより、ガスのまま大気中に飛散することによる二次汚染の心配がなくなる。
【００５０】
第２の実施の形態
本実施の形態においては、本発明方法をメタノールＣＨ_３ＯＨと水素Ｈとを合成物質として二酸化炭素ＣＯ_２の過熱蒸気を溶媒として２分子のメタノールを合成する場合に適用している。
【００５１】
第１の実施の形態におけると同様にして、メタノールと水素と二酸化炭素との混合過熱蒸気を蒸気発生装置５において生成し、該過熱蒸気に反応装置７内において超音波を照射すると、次式に示す反応によりギ酸メチルＨＣＯＯＣＨ_３が生成される。
【００５２】
ＣＨ_３ＯＨ＋ＣＯ_２＋Ｈ_２→ＨＣＯＯＣＨ_３＋Ｈ_２Ｏ
その後、上記ギ酸メチルを水素で還元すると、次式に示す反応により２分子のメタノールが生成する。
【００５３】
ＨＣＯＯＣＨ_３＋２Ｈ_２→２ＣＨ_３ＯＨ
なお、この場合、気液分離装置および無害化装置は不要である。
【００５４】
上記したように本実施の形態においても、超音波の反応装置７内へ照射により、二酸化炭素が超音波の高音圧部において高温高圧流体となり、上記反応が速やかに進行するのである。
【００５５】
なお、この合成反応は、上記の例に限定されることなく、その他の合成例に適用可能なことは勿論である。
【００５６】
【発明の効果】
本願発明によれば、溶媒と反応物質とを所定温度に加熱して得られる過熱混合蒸気に対して所定の周波数と出力を有する超音波を照射することにより、前記過熱混合蒸気中に部分的な高温高圧流体を生成し、該高温高圧流体により与えられる活性化エネルギーにより前記過熱混合蒸気に所定の化学反応を起こさせるようにしているので、超音波の照射により現出される高音圧部が超臨界状態あるいは超臨界状態に近い高温高圧状態として短時間で反転して分子の移動速度が大きくなる結果、分子同士の衝突、分裂作用が連続的に発生することとなり、分子同士の衝突、分裂が基本である物質の化学反応が大幅に加速されるという優れた効果がある。
【００５７】
しかも、過熱混合蒸気全体を超臨界状態あるいは超臨界状態に近い高温高圧状態とすることなく、超音波照射による高圧部分のみで超臨界状態あるいは超臨界状態に近い高温高圧状態が現出できることとなるため、反応に要する温度・圧力条件を低く設定できるという効果もある。
【図面の簡単な説明】
【図１】本願発明の実施の形態にかかる高温高圧流体を利用した反応方法に用いられる反応装置の概略構成を示すシステム図である。
【図２】本願発明の実施の形態にかかる高温高圧流体を利用した反応方法に用いられる反応装置において超音波照射により現出される超音波定在波を示す説明図である。
【図３】前記超音波定在波における点Ａの音圧の時間的変化を示す特性図である。
【図４】（イ）は反応装置内におけるｔ_１時とｔ_２時とにおける粒子の状態を示し、（ロ）はそれぞれの時の超音波の波形を示す。
【図５】模式的Ｐ−Ｔ線図である。
【図６】自由エネルギーの経時変化を示す特性図である。
【符号の説明】
５は過熱蒸気生成手段（蒸気発生装置）、７は反応手段（反応装置）、９は超音波照射手段、１０は超音波ホーン、１１は発振子、１２は超音波発振器。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a reaction method and apparatus using a high-temperature and high-pressure fluid.
[0002]
[Prior art]
It has been pointed out that chlorofluorocarbon gas, which has been used as a refrigerant, and halon gas, which has been used as a digestive agent, are environmental pollutants. From the viewpoint of detoxifying these substances to protect the global environment, It has become a concern.
[0003]
However, it is difficult to decompose the above-mentioned chlorofluorocarbon and halon gas into harmless substances, and various attempts have been made. For example, regarding the CFC treatment method, superheated steam decomposition method, incineration method, explosion reaction decomposition method, microbial decomposition method, ultrasonic decomposition method, plasma reaction method and the like have been proposed.
[0004]
Among the above-mentioned treatment methods, the superheated steam decomposition method is not limited to chlorofluorocarbon gas, but includes organic solvents such as chlorobenzene, waste oil, dioxin, PCB, various plastics, various rubbers, manure, wood, paper, and other industrial waste. It is attracting attention as a versatile treatment method for the entire substance to be decomposed. According to this superheated steam decomposition method, for example, it is possible to decompose CFC gas into hydrogen fluoride HF, hydrogen chloride HCl, carbon dioxide CO ₂ or the like.
[0005]
In the superheated steam decomposition method, the mixture of superheated steam and chlorofluorocarbon gas is kept for a predetermined time under a predetermined temperature condition to hydrolyze the chlorofluorocarbon gas, then cooled, and further rendered harmless by a treatment such as neutralization. However, even if the hydrolysis reaction is carried out under conditions of high temperature and high pressure, a relatively long reaction time is required.
[0006]
[Problems to be solved by the invention]
By the way, in recent years, a decomposition method using a supercritical fluid has attracted attention as a decomposition method for hardly decomposed substances. This supercritical fluid is a fluid under a temperature and pressure condition that exceeds the critical point (that is, the upper limit of the region where the gas-liquid parallel state is established), and has a property intermediate between gas and liquid. ing. The characteristics of this supercritical fluid are that the density changes drastically in the vicinity of the critical point due to slight changes in temperature or pressure, those with high molecular weight and high boiling point dissolve relatively well, the viscosity is as small as gas, and the diffusion coefficient is It is in a point that is significantly larger than liquid.
[0007]
By utilizing the unique properties of the supercritical fluid as described above, it is possible to efficiently decompose difficult-to-decompose substances or synthesize chemical substances. It is necessary to put the decomposition substance under high temperature and high pressure conditions, which leads to an increase in the size and cost of the apparatus.
[0008]
The present invention has been made in view of the above points. By using a superheated steam method and a method using a supercritical fluid or a high-temperature and high-pressure fluid approximate to a supercritical fluid, the temperature and pressure conditions during the reaction can be lowered. The purpose is to increase the reaction rate even if it is set.
[0009]
[Means for Solving the Problems]
In the method of the present invention, as a method for solving the above-mentioned problem, by applying ultrasonic waves having a predetermined frequency and output to superheated mixed steam obtained by heating a solvent and a reactant to a predetermined temperature. A partial high-temperature high-pressure fluid is generated in the superheated mixed steam, and a predetermined chemical reaction is caused to occur in the superheated mixed steam by activation energy given by the high-temperature high-pressure fluid.
[0010]
As described above, the high pressure portion and the low pressure portion appear in the superheated mixed steam due to the sound pressure of the ultrasonic waves, and this is repeated alternately. As a result, the high pressure portion becomes a supercritical state or a high temperature and high pressure state close to the supercritical state, while the low pressure portion becomes a vacuum state. Since this state reverses in a short time, the moving speed of the molecules increases, and collisions between molecules and splitting action occur continuously. Therefore, the energy for activation is given, and the chemical reaction of the substance whose basis is collision and splitting between molecules is greatly accelerated.
[0011]
In addition, a supercritical state or a high-temperature and high-pressure state close to the supercritical state can be realized only by a high-pressure portion by ultrasonic irradiation without bringing the whole superheated mixed steam into a supercritical state or a high-temperature and high-pressure state close to the supercritical state. Therefore, the temperature and pressure conditions required for the reaction can be set low.
[0012]
In order to solve the above problems, the apparatus of the present invention comprises a superheated steam generating means for heating the solvent and the reactant to a predetermined temperature, a reaction means for reacting the superheated mixed steam obtained by the superheated steam generating means, The reaction means includes an ultrasonic irradiation means for irradiating the superheated mixed steam with ultrasonic waves having a predetermined frequency and output.
[0013]
By configuring as described above, the high pressure portion and the low pressure portion appear in the superheated mixed steam in the reaction means due to the sound pressure of the ultrasonic wave irradiated by the ultrasonic irradiation means, and this is repeated alternately. As a result, the high pressure portion becomes a supercritical state or a high temperature and high pressure state close to the supercritical state, while the low pressure portion becomes a vacuum state. Since this state reverses in a short time, the moving speed of the molecules increases, and collisions between molecules and splitting action occur continuously. Therefore, the chemical reaction of substances based on collision and splitting of molecules is greatly accelerated.
[0014]
In addition, a supercritical state or a high-temperature and high-pressure state close to the supercritical state can be realized only by a high-pressure portion by ultrasonic irradiation without bringing the whole superheated mixed steam into a supercritical state or a high-temperature and high-pressure state close to the supercritical state. Therefore, the temperature and pressure conditions required for the reaction can be set low.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.
[0016]
First Embodiment A reaction method using a high-temperature and high-pressure fluid according to this embodiment is carried out using an apparatus as shown in FIG. 1 in order to decompose a hardly decomposable substance such as Freon. Used.
[0017]
The hard-to-decompose substances targeted by this method are organic compounds that are stable, but are not particularly limited, organic solvents such as chlorofluorocarbon and trichrene, waste oil, dioxin, PCB, manure and other industrial waste, wood Any object such as paper, rubber, etc., and its state is not particularly limited regardless of whether it is solid, liquid or gas. In addition, (1) organic compounds that are useful but difficult to treat after use and harmful ones such as chlorofluorocarbons (halogen hydrocarbons), chlorobenzene, dioxins in question, etc. are currently used. There are no PCBs, and (2) organic compounds that are useful but extremely stable and not harmful but difficult to process, such as PE, plastic, rubber and the like.
[0018]
The solvent used in the present embodiment may be any solvent as long as it becomes a vapor by heating, but the optimal one is water. Caustic soda solution and hydrogen peroxide solution can also be used.
[0019]
In FIG. 1, reference numeral 1 is a substance tank for storing a substance to be decomposed (for example, chlorofluorocarbon), 2 is a solvent tank for storing a solvent (for example, water), and 3 and 4 are for pumping the substance to be decomposed and the solvent. The fluid pump 5 is a steam generator that acts as superheated steam generation means, and the liquid to be treated and the solvent are pumped into the steam generator 5 by the fluid pumps 3 and 4, and the heater 6 in the steam generator 5. Heated to superheated steam.
[0020]
The superheated steam generated in the steam generator 5 is sent to a reaction device 7 acting as a reaction means via a pipe. The reactor 7 is for performing a decomposition process by allowing a superheated steam of a substance to be decomposed and a solvent to pass through after a predetermined time while maintaining a predetermined temperature, and is capable of holding the superheated steam for a predetermined reaction time. If it is a thing. Reference numeral 8 denotes a heater for maintaining the temperature in the reaction apparatus 7.
[0021]
The inside of the reactor 7 is not pressurized, and the discharge port side is open to the atmosphere. That is, the pressure of the piping on the inlet side is a pressure gradient only of pressure loss due to the pipeline. In the reaction apparatus 7, a slight pressure is naturally generated by the superheated steam, and a substance to be decomposed is transferred as a pressure gradient.
[0022]
Thus, the reaction device 7 is provided with ultrasonic irradiation means 9 for irradiating the superheated steam with ultrasonic waves having a predetermined frequency and output in the reaction device 7. The ultrasonic irradiation means 9 includes an ultrasonic horn 10 having an oscillator 11 for ultrasonic oscillation, and an ultrasonic oscillator 12 for oscillating the oscillator 11.
[0023]
When ultrasonic irradiation is performed by the ultrasonic irradiation means 9, an ultrasonic standing wave F is formed in the reaction apparatus 7 as shown in FIG. 2. For example, looking at the temporal change of the sound pressure Ps at the point A in FIG. 2, as shown in FIG. 3, a portion where the sound pressure Ps exceeds the critical pressure Pc (that is, a hatched portion) X is in a supercritical state. together with the opposite side (i.e., the sound pressure Ps P ₀ following part) becomes a vacuum state. Since this state is repeated in a short time (that is, the cycle of ultrasonic waves), molecules existing in the reaction device 7 (that is, molecules of the substance to be decomposed and solvent) are given a large acceleration, and at a high speed. Molecules repeat collisions. In other words, if the temperature and pressure state of the high-pressure part are set so as to satisfy the high-temperature and high-pressure conditions close to the supercritical or supercritical state of the solvent, the high-temperature and high-pressure state close to the supercritical state or supercritical state can be easily set in the reactor 7. Therefore, an energy state that can be obtained only in a supercritical state or a high temperature and high pressure state close to the supercritical state can be obtained discontinuously.
[0024]
By the way, the position of the substance particle and the state of ultrasonic waves at t ₁ and t ₂ (t ₁ <t ₂ ) during ultrasonic irradiation are as shown in FIGS. Moves repeatedly with a period T of ultrasonic waves, such as a → b, c → b, d.
[0025]
The sound pressure Ps of the ultrasonic wave is Ps = 2ωρAsin (2π / λ) x · sinωt
Indicated by
[0026]
Here, A: a constant that varies depending on the substance λ: wavelength ω: angular velocity x: position ρ: medium density At this time, when x = 0, λ / 2, λ, P = 0
When x = λ / 4, 3λ / 4 ··· P = 2ωρA is the maximum and the sound pressure is
Z ₀ = P / v = ρC (Pa · s / m = N · s / m ³ )
Here, Z ₀ : inherent acoustic impedance C: sound velocity ρ: density v: particle velocity, and the relationship with intensity is I = Pv = v ² Z ₀ (w / m ₂ )
Therefore, if the required sound pressure determines the intensity and the input voltage to the oscillator is determined, an arbitrary pressure can be obtained.
[0027]
Also, compression by ultrasonic waves is adiabatic compression. [0028]
[Expression 1]

[0029]
Here, k = Cp / Cv: specific heat ratio.
[0030]
Since the temperature rise as shown in the above formula (1) or formula (2) is obtained, the activation energy required for the decomposition is further increased. Moreover, since the substance which changes into a stable substance or is in the middle of reaction undergoes adiabatic expansion in a half cycle, it is rapidly cooled, and the generation of by-products is reduced.
[0031]
Incidentally, according to the schematic PT diagram shown in FIG. 5, the superheated steam irradiated with ultrasonic waves changes from the state of point A to the state of point B through the state of point C. That is, adiabatic compression in the process of A → C → B and adiabatic expansion of B → C → A are repeated.
[0032]
Looking at the profile of the free energy G of the chemical reaction at this time, as shown in FIG. 6, the state of the point D is changed to the state of the point F through the state of the point E, and the chemical reaction is completed. Here, G ′ represents activation energy, and G ₂ −G ₁ = ΔG proceeds in a direction that becomes negative due to a change in free energy.
[0033]
This activation energy G ′ is absolutely necessary for the chemical reaction to proceed, and this energy G ′ is not in the supercritical state (ie, point B in FIG. 5), but is in a high temperature and high pressure state close to the supercritical state. (That is, it may also be obtained at point C in FIG. 5). For example, chlorofluorocarbon can be sufficiently decomposed even in a high temperature and high pressure state close to a supercritical state. In addition, chlorobenzene etc. cannot be decomposed unless it is in a supercritical state.
[0034]
Since the activation energy G ′ (in other words, increase dG of free energy G) described above becomes an isentropic change in the adiabatic change,
dG = dH−TdS
Given in.
[0035]
Here, since dS = 0, dG = dH, which is equal to the enthalpy change.
[0036]
This time,
ΔH = mCp (T ₂ −T ₁ ) = (k / k−1) (p ₂ V ₂ −p ₁ V ₁ )
The free energy increases.
[0037]
Also, considering only the adiabatic compression part, there is a rapid pressure increase, so if you think that the temperature is almost constant,
G ₂ −G ₁ = mRTln (p ₂ / p ₁ )
And free energy will still increase.
[0038]
That is, ΔS = 0 as a whole in consideration of compression / expansion, but when viewed locally in response, the activation energy G ′ can be easily obtained as described above.
[0039]
As described above, the solvent in the reactor 7 is not a continuous supercritical state or a high-temperature and high-pressure state close to the supercritical state, but the high sound pressure portion repeatedly generated in the cycle of the ultrasonic wave is a supercritical state or a supercritical state. It becomes a high temperature and high pressure state close to the state. That is, a supercritical fluid or a high-temperature and high-pressure fluid close to the supercritical fluid appears in the reactor 7. On the other hand, the decomposition of the substance to be decomposed is based on collision between molecules, so that the collision speed of solvent molecules is further accelerated by the repetition of the above supercritical state or high temperature and high pressure state close to the supercritical state, and the kinetic energy is remarkably large. In addition, activation energy in a supercritical state or in a high temperature and high pressure state close to the supercritical state can be obtained at the same time. Accordingly, the reaction rate (in other words, the decomposition rate) in the reaction apparatus 7 becomes even faster than in a normal supercritical state, a high-temperature high-pressure state close to the supercritical state, or a superheated steam state.
[0040]
Further, the product gas generated by the decomposition of the substance to be decomposed in the reaction device 7 is sent to the cooling device 13, where the generated gas is cooled and liquefied by heat exchange with cooling water. The product liquefied by the cooling device 13 (in a gas-liquid mixed state) is sent to the gas-liquid separation device 14 and separated into a liquid and a gas. The gas thus separated is sent to the detoxification device 15, detoxified by neutralization, etc., and then released to the atmosphere. The separated liquid is stored in a waste liquid tank (not shown).
[0041]
Next, the operation mode will be described below by taking as an example the case of decomposing chlorofluorocarbon, which is an environmental pollutant and a hardly decomposable substance.
[0042]
Both chlorofluorocarbon and chlorofluorocarbon are introduced into the decomposed substance tank 1 and water is introduced into the solvent tank 2 and the fluid pumps 3 and 4 are driven to feed chlorofluorocarbon and water as a solvent into the steam generator 5. Are mixed in an appropriate ratio.
[0043]
The steam generator 5 is preheated by a heater 6, and both of them are evaporated in the steam generator 5 to generate superheated steam at about 400 ° C. In addition, since the temperature of the superheated steam required for carrying out a decomposition process changes with substances to be decomposed, each is set according to the substance to be decomposed.
[0044]
The superheated steam obtained as described above is transferred to the reaction apparatus 7 by the pressure gradient, and the reaction apparatus 7 is in a superheated state so that the temperature of the superheated steam transferred by driving the heater 8 can be maintained. Is held in. The reactor 7 is held until a predetermined reaction time elapses while superheated steam passes, but at the same time, an ultrasonic wave having a predetermined frequency and output from the ultrasonic horn 10 is driven by the ultrasonic oscillator 12. 7 is irradiated. Then, as described above, a supercritical state or a high-temperature and high-pressure state close to the supercritical state appears in the high sound pressure portion of the ultrasonic wave in the superheated solvent of the solvent, and the hydrolysis of Freon proceeds rapidly according to the following equation. . Here, the frequency of the ultrasonic waves is preferably about 15 kHz to 300 kHz.
[0045]
CCl ₂ F ₂ + 2H ₂ O → CO ₂ + 2HF + 2HCl
Incidentally, when the reaction temperature and reaction pressure in the hydrolysis reaction were compared between the conventional method and the method of the present invention, the results shown in Table 1 were obtained.
[0046]
[Table 1]

[0047]
According to the above results, according to the method of the present invention, a partial high pressure (that is, only the high sound pressure portion is in a supercritical state or without high reaction temperature and high pressure in the whole reactor 7) It can be seen that CFC hydrolysis proceeds rapidly in a high temperature and high pressure state close to a supercritical state.
[0048]
The product gas generated by the hydrolysis of CFC in the reaction device 7 as described above is sent to the cooling device 13 and liquefied by cooling. The temperature of the cooling device 13 may be such that the generated gas can be liquefied. In the case of chlorofluorocarbon decomposition, the temperature is about 18 ° C., which is the temperature at which hydrogen fluoride HF in the generated gas liquefies.
[0049]
The product liquefied as described above is separated into a gas and a liquid in the gas-liquid separation device 14, and the gas is detoxified in the detoxification device 15 and then released into the atmosphere. On the other hand, the separated liquid is stored in a waste liquid tank (not shown). By liquefying in this way, generation of by-products is prevented. In addition, by liquefying, there is no need to worry about secondary contamination due to scattering in the atmosphere as a gas.
[0050]
Second Embodiment In the present embodiment, the method of the present invention is applied to the case of synthesizing two molecules of methanol using methanol CH ₃ OH and hydrogen H as a synthesis substance and superheated steam of carbon dioxide CO ₂ as a solvent. ing.
[0051]
In the same manner as in the first embodiment, when mixed superheated steam of methanol, hydrogen and carbon dioxide is generated in the steam generator 5 and the superheated steam is irradiated with ultrasonic waves in the reactor 7, the following equation is obtained. The reaction shown produces methyl formate HCOOCH ₃ .
[0052]
CH ₃ OH + CO ₂ + H ₂ → HCOOCH ₃ + H ₂ O
Thereafter, when the methyl formate is reduced with hydrogen, bimolecular methanol is produced by the reaction shown in the following formula.
[0053]
HCOOCH ₃ + 2H ₂ → 2CH ₃ OH
In this case, the gas-liquid separator and the detoxifying device are not necessary.
[0054]
As described above, also in the present embodiment, by irradiating the ultrasonic reaction device 7, carbon dioxide becomes a high-temperature and high-pressure fluid in the high sound pressure portion of the ultrasonic wave, and the reaction proceeds promptly.
[0055]
Of course, this synthesis reaction is not limited to the above example, but can be applied to other synthesis examples.
[0056]
【The invention's effect】
According to the present invention, the superheated mixed steam obtained by heating the solvent and the reactants to a predetermined temperature is irradiated with ultrasonic waves having a predetermined frequency and output, whereby a part of the superheated mixed steam is obtained. A high-temperature and high-pressure fluid is generated, and a predetermined chemical reaction is caused to occur in the superheated mixed steam by the activation energy given by the high-temperature and high-pressure fluid. As a result of inversion in a short time in a high temperature and high pressure state close to the critical state or supercritical state, the movement speed of the molecules increases, resulting in the continuous collision and splitting of the molecules, and the collision and splitting of the molecules. There is an excellent effect that the chemical reaction of the basic substance is greatly accelerated.
[0057]
In addition, a supercritical state or a high-temperature and high-pressure state close to the supercritical state can be realized only by a high-pressure portion by ultrasonic irradiation without bringing the whole superheated mixed steam into a supercritical state or a high-temperature and high-pressure state close to the supercritical state. Therefore, there is an effect that the temperature and pressure conditions required for the reaction can be set low.
[Brief description of the drawings]
FIG. 1 is a system diagram showing a schematic configuration of a reaction apparatus used in a reaction method using a high-temperature and high-pressure fluid according to an embodiment of the present invention.
FIG. 2 is an explanatory diagram showing an ultrasonic standing wave that appears by ultrasonic irradiation in a reaction apparatus used in a reaction method using a high-temperature and high-pressure fluid according to an embodiment of the present invention.
FIG. 3 is a characteristic diagram showing temporal changes in sound pressure at point A in the ultrasonic standing wave.
4A shows the state of particles at t ₁ and t ₂ in the reaction apparatus, and FIG. 4B shows the waveform of ultrasonic waves at each time.
FIG. 5 is a schematic PT diagram.
FIG. 6 is a characteristic diagram showing a change in free energy with time.
[Explanation of symbols]
5 is a superheated steam generation means (steam generation apparatus), 7 is a reaction means (reaction apparatus), 9 is an ultrasonic irradiation means, 10 is an ultrasonic horn, 11 is an oscillator, and 12 is an ultrasonic oscillator.

Claims (2)

By irradiating the superheated mixed steam obtained by heating the solvent and the reactant to a predetermined temperature with ultrasonic waves having a predetermined frequency and output, a partial high-temperature high-pressure fluid is generated in the superheated mixed steam. A reaction method using a high-temperature high-pressure fluid, wherein a predetermined chemical reaction is caused to occur in the superheated mixed steam by activation energy given by the high-temperature high-pressure fluid. A superheated steam generating means for heating the solvent and the reactant to a predetermined temperature; a reaction means for reacting the superheated mixed steam obtained by the superheated steam generating means; A reaction apparatus using a high-temperature and high-pressure fluid, comprising an ultrasonic wave irradiation means for irradiating an ultrasonic wave having a frequency and an output.

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