Laser chemistry synthesis of NF.sub.4 BF.sub.4

Abstract

A process for producing the product NF.sub.4 BF.sub.4 by subjecting gases .sub.3, BF.sub.3, and a gaseous source of a compound which releases fluorine gas when subjected to a tuned CO.sub.2 laser source to cause the product NF.sub.4 BF.sub.4 to precipitate and be collectable. This product can be produced in a closed chamber system or in a continuous flow system at room temperature.

Description

BACKGROUND OF THE INVENTION

In the past, the product NF.sub.4 BF.sub.4 has been produced through a photolysis reaction of NF.sub.3, BF.sub.3 and fluorine gas (F.sub.2) using Hg-lamp and reacting at liquid nitrogen temperature. This is not a preferred way of producing the desired product due to the temperatures required for causing the reaction to take place and due to the cast of producing the product. In the prior art, the reaction is much more costly than is desirable.

Therefore, it is an object of this invention to provide a more economical way for producing NF.sub.4 BF.sub.4.

Another object of this invention is to produce a more economical process for producing NF.sub.4 BF.sub.4 by reacting chemicals at room temperature and using infrared photons which cost much less than the photons produced from Hg-lamp.

Still another object of this invention is to provide a process in which cryogenic temperatures are not required for producing the desired product.

A still further object of this invention is to provide a chemical process for producing NF.sub.4 BF.sub.4 in which less corrosive chemicals are used.

SUMMARY OF THE INVENTION

In accordance with this invention, the gases NF.sub.3, BF.sub.3 and a gaseous source of a compound which releases fluorine gas when subjected to a tuned CO.sub.2 laser at room temperature are reacted to produce the reaction product NF.sub.4 BF.sub.4 as a precipitate and a gaseous byproduct.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Synthesis of the reaction product NF.sub.4 BF.sub.4 is accomplished in accordance with this invention by placing the gases NF.sub.3, BF.sub.3, and SF.sub.6 in a reaction chamber in a molar ratio of each of the gases in a 1:1 mole ratio or with an excess mole ratio of the SF.sub.6 gas. The reaction is carried out at room temperature of about 25.degree. C .+-. 5.degree. C. Also, in order to cause the reaction to go, pulsed CO.sub.2 laser radiation tuned to the P.sub.14 - P.sub.20 lines is used to irradiate the gases in an appropriate reaction chamber. The reaction product (NF.sub.4 BF.sub.4) precipitates out and gaseous SF.sub.4 is pumped off in a conventional manner. A schematic illustration of the reaction is illustrated in the blocks hereinbelow: ##STR1##

Another way of producing the reaction product NF.sub.4 BF.sub.4 is by placing gases NF.sub.3, BF.sub.3 and N.sub.2 F.sub.4 in an appropriate reaction vessel with the gases being present in a 1:1 mole ratio or with an excess mole ratio of the N.sub.2 F.sub.4 gas. The gases are subjected to pulsed CO.sub.2 laser radiation tuned to the P.sub.14 - P.sub.20 lines to irradiate the bases in the reaction vessel. The reaction product NF.sub.4 BF.sub.4 precipitates out and the other reaction product N.sub.2 F.sub.3 is pumped off in a conventional manner. This reaction proceeds in accordance with the general formula illustrated hereinbelow: ##STR2##

An appropriate reaction vessel for either of the reactions above can comprise a simple cylindrical gas cell of about 1 inch by 4 inches with salt windows on either end through which the laser radiation is injected. Also, this reaction can be carried out in a continuous flow system by continuously exposing the reaction gases to pulsed CO.sub.2 laser radiation to produce pound quantities of the reaction product NF.sub.4 BF.sub.4. The reaction product NF.sub.4 BF.sub.4 is a product that is used as a fluorine fuel for the HF chemical laser.

EXAMPLE

20 torr each of the gases NF.sub.3, BF.sub.3, and SF.sub.6 were placed in a stainless steel reaction chamber of a simple cylindrical gas cell one inch by four inches with salt windows on either end. Pulsed CO.sub.2 radiation tuned to the P.sub.14 - P.sub.20 lines was used to radiate the cell through one of the salt windows. The reaction was carried out at room temperature as set forth hereinabove and the reaction product (NF.sub.4 BF.sub.4) precipitated out in the cell and gaseous SF.sub.4 which was the other reaction product was pumped off in a conventional manner. In this reaction, an excess of more than one molar ratio of SF.sub.6 can be used. The criticality being that at least one mole ratio of SF.sub.6 be used in order to efficiently produce the reaction product NF.sub.4 BF.sub.4.

Claims

1. A process for producing NF.sub.4 BF.sub.4 comprising placing the gases NF.sub.3, BF.sub.3 and a gaseous compound that gives up fluorine when subjected to laser energy in a reaction container at room temperature and subjecting the gases to a CO.sub.2 laser source for irradiating the reaction chamber and producing NF.sub.4 BF.sub.4 as a precipitate.

2. A process for producing NF.sub.4 BF.sub.4 as set forth in claim 1, wherein said gaseous compound that gives up free fluorine is SF.sub.6, wherein said CO.sub.2 laser source is tuned to the P.sub.14 - P.sub.20 lines, and wherein said room temperature is about 25.degree. C .+-. 5.degree. C.

3. A process for producing NF.sub.4 BF.sub.4 as set forth in claim 2, wherein said gases are continuously passed through a flow system and said CO.sub.2 laser source is pulsed to produce substantial quantities of the product NF.sub.4 BF.sub.4.

4. A process for producing NF.sub.4 BF.sub.4 as set forth in claim 1, wherein said gaseous compound that gives up free fluorine is N.sub.2 F.sub.4, wherein said CO.sub.2 radiation is tuned to the P.sub.14 - P.sub.20 lines, and wherein said room temperature is about 25.degree. C .+-. 5.degree. C.

5. A process for producing NF.sub.4 BF.sub.4 as set forth in claim 4, wherein said gases continuously flow through a flow system and said CO.sub.2 laser source is pulsed to produce substantial quantities of the product NF.sub.4 BF.sub.4.

6. A process for producing NF.sub.4 BF.sub.4 as set forth in claim 3, wherein said gases are present in an amount of about 1 mole ratio each.

7. A process for producing NF.sub.4 BF.sub.4 as set forth in claim 5, wherein said gases are present in an amount of about 1 mole ratio each.