초록 ▼

The present invention provides a method for preparing a catalyst for the reduction of nitrogen oxides by the use of natural gas as a reducing agent in an excess oxygen atmosphere, which comprises of filling zeolite with an organic compound having molecular weight of 100＿250 prior to loading catalyti

The present invention provides a method for preparing a catalyst for the reduction of nitrogen oxides by the use of natural gas as a reducing agent in an excess oxygen atmosphere, which comprises of filling zeolite with an organic compound having molecular weight of 100＿250 prior to loading catalytically active noble metal components on a zeolite. Since the method according to the present invention supports catalytic active noble metal components on a zeolite under the condition that the pores of zeolite are filled with organic compounds, the noble metal component, which is essential for forming highly active NOx reduction catalyst, can be supported precisely on the desired positions of zeolite pores. Therefore, the NOx reduction catalysts prepared by the present invention are very useful for the purification of exhaust gas in an excessive oxygen atmosphere such as gas turbines, boilers or lean-burn automobiles.

대표청구항 ▼

The present invention provides a method for preparing a catalyst for the reduction of nitrogen oxides by the use of natural gas as a reducing agent in an excess oxygen atmosphere, which comprises of filling zeolite with an organic compound having molecular weight of 100＿250 prior to loading catalyti

The present invention provides a method for preparing a catalyst for the reduction of nitrogen oxides by the use of natural gas as a reducing agent in an excess oxygen atmosphere, which comprises of filling zeolite with an organic compound having molecular weight of 100＿250 prior to loading catalytically active noble metal components on a zeolite. Since the method according to the present invention supports catalytic active noble metal components on a zeolite under the condition that the pores of zeolite are filled with organic compounds, the noble metal component, which is essential for forming highly active NOx reduction catalyst, can be supported precisely on the desired positions of zeolite pores. Therefore, the NOx reduction catalysts prepared by the present invention are very useful for the purification of exhaust gas in an excessive oxygen atmosphere such as gas turbines, boilers or lean-burn automobiles. he stoichiometry of the perovskite structure metal oxides is adjusted so that the atomic ratio of ions at A-locations to ions at B-locations is between 0.7 and 1.3. 6. The measuring transformer according to claim 1, wherein the two resistive oxygen sensors consist of different materials. , which prevails in said cavity, has a value in excess of 3 MPa. 5. The apparatus as defined in claim 2, wherein: said restrictor body constitutes a lamina having a predetermined thickness and a stepped throughbore; said stepped throughbore defining said restrictor opening which has a predetermined length, and a remaining portion of said throughbore; said predetermined thickness of said lamina exceeding said predetermined length of said restrictor opening; and said remaining portion of said stepped throughbore tapering toward said restrictor opening. 6. The apparatus as defined in claim 1, wherein: said body defining said cavity constitutes a hollow body having the shape of a tube; said tube being made of a chemically highly resistant material which is electrically non-conductive; and said heating means comprising a heating coil surrounding said tube and connected to a source of electric energy. 7. The apparatus as defined in claim 1, wherein: said tube is made of a chemically highly resistant material; said tube having the shape of a capillary coil; and said heating means comprising a heat transfer medium into which said capillary coil is immersed. 8. The apparatus as defined in claim 1, wherein: said tube is made of a chemically highly resistant material which is electrically conductive; and said heating means comprising a source of electrical energy connected to said tube. 9. The apparatus as defined in claim 8, wherein said tube is made of a platinum-iridium alloy. 10. The apparatus as defined in claim 1, further including: infeed means interposed between said output side of said high pressure pump and said inlet side of said cavity; said source of liquid connected to said input side of said high pressure pump constituting a carrier liquid reservoir; and said infeed means including a sample loop for infeeding a liquid sample into said carrier liquid which is pumped by said high pressure pump into said cavity. 11. The apparatus as defined in claim 10, wherein: said flow restrictor comprises a restrictor opening; and said flow restrictor generating on the outlet side of said restrictor opening an aerosol of said liquid sample. 12. The apparatus as defined in claim 10, wherein said source of liquid connected to said input side of said high pressure pump constitutes a liquid digestant reservoir. 13. The apparatus as defined in claim 10, wherein: said infeed means containing a first loop including first valve means and second valve means, and a second loop; said first valve means selectively connecting said first loop to said inlet side of said cavity; said second valve means selectively connecting said second loop and said first loop; said first loop containing a liquid digestant; and said second loop containing said liquid sample and said liquid digestant. 14. The apparatus as defined in claim 11, further including: drying means connected to said flow restrictor; said liquid sample comprising a solid sample dissolved in a liquid solvent; said aerosol substantially containing said solid sample; said drying means comprising a heating chamber connected to said restrictor opening for vaporizing any solvent which is present in said aerosol issuing from said restrictor opening; and said drying means further comprising a cooling chamber following said heating chamber for removing by condensation said solvent vaporized in said heating chamber. 15. The apparatus as defined in claim 11, further including: an atomic spectrometer comprising an atomizer for receiving and atomizing a sample; and said atomizer receiving said aerosol issuing from said restrictor opening. 16. The apparatus as defined in claim 15, wherein: said atomizer comprises a burner and a mixing chamber connected to a source of combustible gas; and said restrictor opening extending into said mixing chamber for mixing said aerosol and said combustible gas. 17. The apparatus as defined in claim 14, fu rther including: an atomic spectrometer comprising a plasma burner for atomizing a sample; and said drying means being connected to said plasma burner for feeding dried aerosol to said plasma burner. 18. The apparatus as defined in claim 10, further including: a high pressure separating column interposed between said infeed means and said cavity; and a high pressure valve assembly interconnecting said high pressure separating column and said cavity. 19. The apparatus as defined in claim 12, additionally including recombining means connected to said restrictor opening for recombining aerosol and liquid issuing from said restrictor opening and forming therefrom a uniform liquid flow. 20. The apparatus as defined in claim 19, wherein: said first section of said body is in the form of a first coiled tube; said heating means comprising a heating bath in which said first coiled tube is immersed; said second section of said body being in the form of a second coiled tube; and said cooling means comprising a cooling bath in which said second coiled tube is immersed. 21. A method of handling a flowing liquid, comprising the steps of: pumping a flow of liquid under pressure through a hollow body defining a cavity having an inlet side, an outlet side, and a substantially uniform cross-sectional area; providing a flow resistance on the outlet side of said cavity by providing a flow restrictor having an opening through which the liquid is expelled having a cross-sectional area through which the liquid must flow, said cross-sectional areas of said cavity and said opening of said flow restrictor being of such a ratio relative to a predetermined flow rate of the liquid through said cavity thereby building up high pressure in said cavity with respect to atmospheric pressure; during said step of pumping said flow of liquid through said cavity, heating said liquid in said cavity to a predetermined temperature sufficient to cause vaporization of said liquid at atmospheric pressure by means of heating said hollow body; wherein said step of building up said high pressure in said cavity entails generating a pressure in excess of the saturated vapor pressure of said liquid at said predetermined temperature such that no vapor and crystallized depositions occur in said cavity at said predetermined temperature; and generating an aerosol of liquid by nebulizing at least a portion of liquid exiting from said flow resistance by means of the reduction in pressure from that prevailing in said cavity to atmospheric pressure causing expansion and vaporization thereof. 22. The method as defined in claim 21, wherein: said step of heating said liquid in said cavity entails electrically heating said hollow body; and automatically controlling said predetermined temperature by regulating the electric heating power supplied for electrically heating said hollow body. 23. The method as defined in claim 21, wherein: said step of heating said liquid in said cavity includes immersing said hollow body in a heating bath; and automatically controlling said predetermined temperature by thermostatting said heating bath. 24. The method as defined in claim 21, further including the steps of: selecting as said liquid, a carrier liquid; during said step of pumping said flow of liquid through said cavity, pumping a flow of said carrier liquid through said cavity; and prior to said step of pumping said flow of carrier liquid through said cavity, infeeding a liquid sample into said flow of carrier liquid. 25. The method as defined in claim 24, wherein said step of selecting said carrier liquid entails selecting a liquid digestant as said carrier liquid. 26. The method as defined in claim 24, wherein said step of infeeding said liquid sample into said flow of carrier liquid entails sequentially infeeding a liquid digestant, a mixture of said liquid digestant and said liquid sample, and said liquid digestant into said flow of carrier liqui d. 27. The method as defined in claim 24, further including the step of generating an aerosol of said liquid sample on the outlet side of said flow resistance. 28. The method as defined in claim 27, further including the step of feeding the aerosol to an atomizer of an atomic spectrometer. 29. The method as defined in claim 28, further including the steps of: selecting as said atomizer of said atomic spectrometer a burner including a mixing chamber; feeding a combustible gas to said mixing chamber of said burner; and said step of feeding said aerosol to said atomizer of said atomic spectrometer entails infeeding said aerosol into said mixing chamber. 30. The method as defined in claim 28, further including the steps of: dissolving a solid sample in a solvent and thereby forming a liquid solution; said step of infeeding said liquid sample into said flow of carrier liquid encompasses infeeding said liquid solution into said flow of carrier liquid; drying said aerosol prior to the step of feeding the same to said atomizer of said atomic spectrometer; and during said step of drying said aerosol, heating said aerosol for vaporizing said solvent in which said solid sample is dissolved, and cooling the heated aerosol and thereby condensing said solvent. 31. The method as defined in claim 30, further including the steps of: selecting a plasma burner as said atomizer of said atomic spectrometer; and feeding said dried aerosol to said plasma burner. 32. The method as defined in claim 24, further including the step of passing the flow of liquid containing said liquid sample through a high pressure separating column prior to pumping said flow of liquid containing said liquid sample through said cavity. 33. The method as defined in claim 25, further including the steps of: subdividing said hollow body defining said cavity into a heating section and a cooling section following said heating section in the direction of flow of said liquid digestant; selecting as said predetermined temperature in said heating section, a temperature sufficient for digesting said liquid sample; cooling said heated flow of liquid digestant in said cooling section to a temperature below the boiling point of said liquid digestant under atmospheric pressure; and producing a substantially uniform liquid flow issuing on the outlet side of said flow resistance by recombining said aerosol and said liquid digestant on the outlet side of said flow resistance. 34. The method as defined in claim 26, further including the steps of: subdividing said hollow body defining said cavity into a heating section and a cooling section following said heating section in the direction of flow of said carrier liquid; selecting as said predetermined temperature in said heating section, a temperature sufficient for digesting said liquid sample; cooling said heated flow of carrier liquid in said cooling section to a temperature below the boiling point of said carrier liquid under atmospheric pressure; and producing a substantially uniform liquid flow issuing on the outlet side of said flow resistance by recombining said aerosol and said carrier liquid on the outlet side of said flow resistance. 35. An apparatus for handling liquids, comprising: a high pressure pump having an input side and an output side; a carrier liquid reservoir connected to said input side of said high pressure pump; a tubular body defining a cavity having an inlet side connecting to a first section of the cavity, an outlet side connecting to a second section of the cavity, and a substantially uniform cross-sectional area; said output side of said high pressure pump being connected to said body at said inlet side of said cavity with infeed means interposed therebetween; said infeed means including a sample loop for infeeding a liquid sample into said carrier liquid which is pumped by said high pressure pump into said cavity, said infeed means comprising; a first loop includin