JPS58219926A - Laser irradiating apparatus - Google Patents

Abstract

PURPOSE:To provide the titled apparatus enhanced in the yield of a reaction product, by promoting the separation of an isotope due to photochemical reaction utilizing laser beam by a magnetic field. CONSTITUTION:Under a state wherein a mixture of Freon 123 and Freon 123-D is injected into an irradiating cell 7 being a reaction container under proper pressure and an electromagnet 8 surrounding the outside of the cell is energized, infrared laser beams 9 are emitted from a laser oscillator 5 by pulse oscillation and gathered by a lens 6 to be irradiated. In the cell 7, dissociation reaction is generated by the absorption of infrared multiple-photon and a radical pair in a singlet and a triplet states is formed. Herein, by a magnetic field formed by the electromagnet 8, the transfer of the radical pair to the triplet state from the singlet state is promoted and the production to CF2=CFD containing diuterium is promoted. By this method, the desired yield of a reaction product per a unit laser beam irradiation can be increased.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of the Invention] The present invention relates to a laser irradiation device that irradiates laser light for the separation of substances using photochemical reactions, particularly for the separation of isotopes.

[Prior art and its problems]

BACKGROUND ART Conventionally, a laser irradiation device as shown in FIG. 1 has been used to select substances by photochemical reactions using laser light, particularly to separate isotopes. This device focuses a laser beam (4) using a lens (2) into a diameter irradiation cell (3).
It is configured to irradiate a gaseous sample inside and cause a photochemical reaction to occur in a region of extremely high energy density.

Example Evasono reaction is 2,2-dichloro-1,1
,1-trifluoroethane (CFICH
CJI; When Freon 123 (trade name) is used, the H atom in Freon 123 (trade name) is replaced with 0 atom, resulting in Freon 123-D. Freon 123 at this time
When infrared spectra are taken for -D and Freon 123 (trade name), there is clearly a difference in the position of their absorption peaks based on isotopic effects. So freon 12
When irradiated with laser light of a wavelength equal to the absorption peak of 3-D, Freon 123-D becomes Freon 123 (
It absorbs a large amount of photons compared to (trade name), and as a result breaks down into other chemical species. This phenomenon is already known as infrared multiphoton absorption dissociation. The reaction at this time is H, Marl
in # et al. (Journal of Chemical P
hyslcs, vol, 72. No. 1 (L
(1980) P, 516), it is explained as follows.

CF, CD-1=→CF, =CFD...
... ■C2+OF, CHCj, --→CF, 6CJ,
4-HCj ・−・・− ■C14-CF, CCJ, 10M-cF, CCL, +M ・−−−■ This result,
Chemicals containing deuterium are cr, = crn and DCJ- and K. However, since the main reaction here is ■, D
The amount of CA is small compared to CF, = CFD.

It, CF, and CHC^ are said to undergo the following reaction with the radicals generated in the above reaction.

cpa6cJt+CF, CHCJ, → cr, ccz,
-4-cr, ccncz...■CFs CHC' 10M-Crt = CFH+ M +07 songs・■I straight ν CF, CDCj, -) CF, CHCJ-, 4CF,
CIX'l, -1-OF, CHCj, -@CkarasuCHCJ
, +M-→OF', -CFH1M+2(:t ,,
, , [Phase] mdirect ν As a result, =CFH to C is generated, which reduces the deuterium enrichment coefficient. However, the rate of this reaction is extremely small, and by selecting an appropriate system, an enrichment factor of υ~1200 has been obtained.

As mentioned above, reaction (2) is the main initial step, and both of its products are in a highly radical state. Immediately after a chemical bond is broken by laser light, two radicals form.For a very short time, the unpaired electron spins of the two products are in a singlet state with opposite orientations, or in a triplet state with the same orientation. form. - Radical pairs in the double ring state tend to react with each other and recombine, but in the triple state they cannot recombine and the pair is dissolved. Therefore, if many 2 radicals exist in the singlet state, the yield of the reaction will decrease. This results in a loss of energy of the laser beam given to the reaction system, which is unfavorable from an economical and efficient standpoint.

[Purpose of the invention]

It is an object of the present invention to provide a laser irradiation device that eliminates these drawbacks and improves the yield of reaction products.

[Summary of the invention]

The present invention is a laser irradiation device in which a laser reaction vessel is placed in a magnetic field.

[Embodiments of the invention]

Embodiments of the present invention will be described based on the drawings.

#I2 figure is the laser irradiation device of the present invention, (5) Fl,
A laser oscillator, (6) a lens, (7) an irradiation cell, (8) an electromagnet, and (9) a laser beam. A mixture of Freon 123 (trade name) and Freon 123-D is injected into the irradiation cell (7) at an appropriate pressure, and the electromagnet (8) surrounding the outside of the cell (7) is activated to irradiate the laser beam. A gas sample in an irradiation cell (7) is irradiated with infrared laser light (9) pulsed from an oscillator (5). In the irradiation cell (7), the reactions from (1) to [phase] mentioned above are carried out by multiphoton absorption of infrared light, but as explained earlier, as a result of the reaction, the state of the radical pair formed is There are doublet and triplet current states, and the doublet and triplet states mutually transform their states by changes in unpaired electron beams. Therefore, since the magnetic field formed by the electromagnet (8) installed outside the cell (7) promotes the transition of radical pairs from the - doublet state to the triplet state, CF
, promotes the production of CDCL, and also promotes the production of CF and CD to CF and =CFD in reactions ① and ②.

〔Effect of the invention〕

The laser irradiation device of the present invention configured in this manner has the effect of increasing the yield of the desired reaction product per unit laser beam irradiation ib, that is, increasing the amount of deuterium recovered in the above reaction. The same goes for tritium, another hydrogen isotope, Freon 123 (trade name)
This also applies when replacing the H atom inside, or even when using another working substance instead of Freo/123 (trade name).

[Brief explanation of the drawing]

Figure 1 is an explanatory diagram showing a conventional laser irradiation device, Figure 2
The figure is an explanatory diagram of a laser irradiation device according to the present invention. 1... Laser oscillator. 2......shins. 3...Irradiation cell. 4...Laser light. 5...Laser oscillator. 6... Cell 7... Irradiation cell. ８・・・・・・Electromagnet. 9...Laser light.

Claims (1)

[Claims] A laser irradiation device characterized in that a reaction vessel of an isotope separation system that causes a photochemical reaction using laser light is installed in a magnetic field.