Nitrogen fixation with a high energy laser

Claim 1

In combination with a high energy repetitively-pulsed laser radiation source that is capable of producing laser radiation of a wavelength that is effective for producing plasmas in gases, a device for fixing nitrogen to form nitric oxide, said device comprising: (a) a reaction chamber; (b) a first inlet means secured to said reaction chamber for introducing into said reaction chamber a reactant gas mixture comprised of nitrogen and oxygen; (c) a second inlet means secured to said reaction chamber for admitting into said reaction chamber said laser radiation wavelength, said second inlet means being a window that is transparent to said laser radiation wavelength; (d) a focusing means positioned within said reaction chamber for concentrating said laser radiation wavelength sufficiently to produce, each time said high energy repetitively-pulsed laser radiation source is pulsed, a plasma wherein said nitrogen and oxygen in said reactant gas mixture are reacted to form nitric oxide in a reacted gas mixture, said nitric oxide being rapidly quenched to a lower temperature to prevent decomposition thereof, said quenching effected by rapid decay of said plasma achieved by the mechanism of recombination and the rapid expansion of said plasma into the surrounding cool gas; and, (e) an outlet means secured to said reaction chamber for extracting said reacted gas mixture containing said nitric oxide.

Claim 5

A method for fixing nitrogen which employs a high energy repetitively-pulsed laser radiation source that is capable of producing plasmas in gases in a reaction chamber wherein said plasma has a sufficiently high temperature to form high concentrations of nitric oxide, said method comprising: (i ) introducing a gas mixture comprising nitrogen and oxygen into a reaction chamber fitted with a first inlet and an outlet means and adapted for operating at an elevated pressure; (ii) admitting laser radiation wavelength in an expanded beam through a second inlet means to said reaction chamber, said laser radiation being admitted in an expanded beam which has irradiance at said second inlet means that is sufficiently low to prevent damage to said second inlet means which is a window transparent to said laser radiation wavelength; (iii) collecting said expanded beam and focusing said expanded beam with a focusing means which is a parabolic focusing mirror to yield an irradiance which is sufficient to produce a plasma at the focal point of said parabolic focusing mirror; (iv) producing a plasma each time said high energy repetitively-pulsed laser radiation source is pulsed to form high concentrations of nitric oxide in said plasma and in a resulting reacted gas mixture, said nitric oxide being rapidly quenched to a lower temperature to prevent decomposition thereof, said quenching effected by rapid decay of said plasma following termination of laser pulse, said rapid decay of said plasma achieved by the mechanism of recombination and the rapid expansion of said plasma into the surrounding cool gas; (v) adjusting the flow rate of said introduced gas mixture and said reacted gas mixture to maximize the yield of said nitric oxide in said reacted gas mixture which is to be extracted to yield said nitric oxide, and, (vi) extracting said reacted gas mixture to effect removal of the nitric oxide present in said extraction reacted gas mixture.

Claim 6

A method for fixing nitrogen which employs a high energy repetitively-pulsed laser radiation source that is capable of producing plasmas in gases in a reaction chamber wherein said plasma has a sufficiently high temperature to form high concentrations of nitric oxide, said method comprising: (i ) introducing a gas mixture comprising nitrogen and oxygen into a reaction chamber fitted with a first inlet and an outlet means and adapted for operating at an elevated pressure; (ii) admitting laser radiation wavelength in an expanded beam through a second inlet means to said reaction chamber, said laser radiation being admitted in an expanded beam which has irradiance at said second inlet means that is sufficiently low to prevent damage to said second inlet means which is a window transparent to said laser radiation wavelength; (iii) collecting said expanded beam and focusing said expanded beam with a focusing means which is a parabolic focusing mirror to yield an irradiance which is sufficient to produce a plasma at the focal point of said parabolic focusing mirror; (iv) producing a plasma each time said high energy repetitively-pulsed laser radiation source is pulsed to form high concentrations of nitric oxide in said plasma and in a resulting reacted gas mixture, said nitric oxide being rapidly quenched to a lower temperature to prevent decomposition thereof, said quenching effected by rapid decay of said plasma following termination of laser pulse, said rapid decay of said plasma achieved by the mechanism of recombination and the rapid expansion of said plasma into the surrounding cool gas; (v) adjusting the flow rate of said introduced gas mixture and said reacted gas mixture to maximize the yield of said nitric oxide in said reacted gas mixture which is to be extracted to yield said nitric oxide, and, (vi) extracting said reacted gas mixture to effect removal of the nitric oxide present in said extraction reacted gas mixture.