Iridium-catalyzed hydrogen peroxide based monopropellant system

Abstract

Rocket propulsion or rapid response gas generation systems and methods are disclosed in which a novel one component, single tank storable, low toxicity, low detonation sensitivity liquid monopropellant containing a mixture of aqueous 70% hydrogen peroxide, alcohol, and water is catalytically decomposed with an iridium based catalyst. The resulting rapidly formed gaseous decomposition products consisting substantially of carbon dioxide and water vapor are used for rocket propulsion, satellite propulsion, divert attitude control systems for interceptor missiles, and other power control systems where a re-start capability is desired.

What is claimed is:  
     
         1 . A gas generation system comprising: 
 a liquid monopropellant comprising a solution of hydrogen peroxide, alcohol, water, and optionally a stabilizer, and    an iridium catalyst for providing rapid catalytic decomposition of the monopropellant solution.    
     
     
         2 . The system of  claim 1 , wherein the catalyst comprises iridium and at least one of ruthenium, iridium, palladium and platinum.  
     
     
         3 . The system of  claim 1 , in which the monopropellant is a class 1.3 one component liquid propellant formulation comprising a solution of stabilized hydrogen peroxide, alcohol, and water; which when catalytically decomposed; forms gaseous products consisting substantially of carbon dioxide and water vapor.  
     
     
         4 . The system of  claim 1 , in which the monopropellant is a class 1.3 one component liquid propellant formulation comprising a solution of stabilized hydrogen peroxide, alcohol, and water; which when catalytically decomposed; forms gaseous products consisting substantially of carbon dioxide, water vapor, and a low concentration of oxygen.  
     
     
         5 . The system of  claim 1 , in which the monopropellant is a class 1.3 one component liquid propellant formulation comprising a solution of stabilized hydrogen peroxide, alcohol, and water; which when catalytically decomposed; forms gaseous products consisting substantially of carbon dioxide, water vapor, and a low concentration of carbon monoxide.  
     
     
         6 . The system of  claim 1 , wherein the alcohol in the liquid monopropellant comprises at least one of methanol and ethanol.  
     
     
         7 . The system of  claim 1 , wherein the alcohol in the liquid monopropellant comprises an ethanol/water mixture.  
     
     
         8 . The system of  claim 1 , wherein the alcohol in the liquid monopropellant comprises a methanol/water mixture.  
     
     
         9 . The system of  claim 1 , wherein the hydrogen peroxide is a stabilized hydrogen peroxide/water mixture.  
     
     
         10 . The system of  claim 1 , wherein the hydrogen peroxide is a water solution containing 60-90 wt % stabilized hydrogen peroxide.  
     
     
         11 . The system of  claim 10 , wherein the water solution contains about 70 wt % hydrogen peroxide.  
     
     
         12 . The system of the system in  claim 1 , in which the water is purified or unpurified.  
     
     
         13 . The system of  claim 1  in which the liquid monopropellant is catalytically decomposed on a supported or unsupported iridium-based catalyst.  
     
     
         14 . The system of  claim 1  in which the liquid monopropellant is catalytically decomposed on a supported or unsupported iridium based catalyst containing ruthenium.  
     
     
         15 . The system of  claim 1 , wherein the catalyst is in the form of granules.  
     
     
         16 . The catalyst of  claim 15 , wherein the size of the granules is about 14-18 mesh.  
     
     
         17 . The system of  claim 1 , wherein the catalyst is deposited onto a porous carrier.  
     
     
         18 . The system of  claim 17 , wherein the porous carrier is comprised of a refractory.  
     
     
         19 . The system of  claim 18 , wherein the refractory comprises at least one of alumina, silica, zirconia, clays, silicates, aluminates and mixtures thereof.  
     
     
         20 . The system of  claim 1 , wherein the stabilizer comprises tin in the form of an alkali metal stannate.  
     
     
         21 . The system of  claim 1 , wherein the stabilizer comprises a nitrogen containing phosphonic acid.  
     
     
         22 . The system of  claim 1 , wherein the stabilizer comprises a phosphonic acid.  
     
     
         23 . The system of  claim 1 , wherein the stabilizer comprises an organophosphonic acid.  
     
     
         24 . The system of  claim 23 , wherein the stabilizer comprises amino tris(methylenephosphonic acid) (ATMP), ethylenediamine tetra(methylenephosphonic acid) (EDTMP), 1-hydroxyethyl-1, 1-diphosphonic acid (HEDP); or mixtures thereof.  
     
     
         25 . The system of  claim 1 , wherein the stabilizer comprises a mixture of a primary stabilizer in the form of an alkali metal stannate with a pyrophosphate of a phosphate for improving the stability of the colloidal stannic oxide formed from the alkali metal stannate.  
     
     
         26 . The system of  claim 1 , wherein the stabilizer comprises a mixture of a primary stabilizer in the form of an alkali metal stannate with a pyrophosphate or phosphate for improving the stability of the colloidal stannic oxide formed from the alkali metal stannate and an organophosphonic acid.  
     
     
         27 . A gas generation method which comprises combusting a gas generant system comprised of: 
 a liquid monopropellant comprising a solution of hydrogen peroxide, alcohol, water, and optionally a stabilizer, and    an irridium catalyst for providing rapid catalytic decomposition of the monopropellant solution.    
     
     
         28 . The system of  claim 27 , wherein the catalyst comprises iridium and at least one of ruthenium, iridium, palladium and platinum.  
     
     
         29 . The system of  claim 27 , in which the monopropellant is a class 1.3 one component liquid propellant formulation comprising a solution of stabilized hydrogen peroxide, alcohol, and water; which when catalytically decomposed; forms gaseous products consisting substantially of carbon dioxide and water vapor.  
     
     
         30 . The system of  claim 27 , in which the monopropellant is a class 1.3 one component liquid propellant formulation comprising a solution of stabilized hydrogen peroxide, alcohol, and water; which when catalytically decomposed; forms gaseous products consisting substantially of carbon dioxide, water vapor, and a low concentration of oxygen.  
     
     
         31 . The system of  claim 27 , in which the monopropellant is a class 1.3 one component liquid propellant formulation comprising a solution of stabilized hydrogen peroxide, alcohol, and water; which when catalytically decomposed; forms gaseous products consisting substantially of carbon dioxide, water vapor, and a low concentration of carbon monoxide.  
     
     
         32 . The system of  claim 27 , wherein the alcohol in the liquid monopropellant comprises at least one of methanol and ethanol.  
     
     
         33 . The system of  claim 27 , wherein the alcohol in the liquid monopropellant comprises an ethanol/water mixture.  
     
     
         34 . The system of  claim 27 , wherein the alcohol in the liquid monopropellant comprises a methanol/water mixture.  
     
     
         35 . The system of  claim 27 , wherein the hydrogen peroxide is a stabilized hydrogen peroxide/water mixture.  
     
     
         36 . The system of  claim 27 , wherein the hydrogen peroxide is a water solution containing 60-90 wt % stabilized hydrogen peroxide.  
     
     
         37 . The system of  claim 36 , wherein the water solution contains about 70 wt % hydrogen peroxide.  
     
     
         38 . The system of the system in  claim 27 , in which the water is purified or unpurified.  
     
     
         39 . The system of  claim 27  in which the liquid monopropellant is catalytically decomposed on a supported or unsupported iridium-based catalyst.  
     
     
         40 . The system of  claim 27  in which the liquid monopropellant is catalytically decomposed on a supported or unsupported iridium based catalyst containing ruthenium.  
     
     
         41 . The system of  claim 27 , wherein the catalyst is in the form of granules.  
     
     
         42 . The catalyst of  claim 41 , wherein the size of the granules is about 14-18 mesh.  
     
     
         43 . The system of  claim 27 , wherein the catalyst is deposited onto a porous carrier.  
     
     
         43 . The system of  claim 43 , wherein the porous carrier is comprised of a refractory.  
     
     
         44 . The system of  claim 44 , wherein the refractory comprises at least one of alumina, silica, zirconia, clays, silicates, aluminates and mixtures thereof.  
     
     
         45 . The system of  claim 27 , wherein the stabilizer comprises tin in the form of an alkali metal stannate.  
     
     
         46 . The system of  claim 27 , wherein the stabilizer comprises a nitrogen containing phosphonic acid.  
     
     
         47 . The system of  claim 27 , wherein the stabilizer comprises a phosphonic acid.  
     
     
         48 . The system of  claim 27 , wherein the stabilizer comprises an organophosphonic acid.  
     
     
         49 . The system of  claim 48 , wherein the stabilizer comprises amino tris(methylenephosphonic acid) (ATMP), ethylenediamine tetra(methylenephosphonic acid) (EDTMP), 1-hydroxyethyl-1,1-diphosphonic acid (HEDP); or mixtures thereof.  
     
     
         50 . The system of  claim 27 , wherein the stabilizer comprises a mixture of a primary stabilizer in the form of an alkali metal stannate with a pyrophosphate of a phosphate for improving the stability of the colloidal stannic oxide formed from the alkali metal stannate.  
     
     
         51 . The system of  claim 27 , wherein the stabilizer comprises a mixture of a primary stabilizer in the form of an alkali metal stannate with a pyrophosphate or phosphate for improving the stability of the colloidal stannic oxide formed from the alkali metal stannate and an organophosphonic acid.  
     
     
         52 . A hydrogen peroxide-based liquid gas generant system which comprises: 
 (i) an aqueous liquid monopropellant comprising a solution of hydrogen peroxide and alcohol, and    (ii) a catalytically effective amount of an iridium catalyst.    
     
     
         53 . The system of  claim 52 , wherein the iridium catalyst includes iridium metal deposited onto a porous carrier.  
     
     
         54 . The system of  claim 53 , wherein the catalyst is supported on a porous refractory carrier.  
     
     
         55 . The system of  claim 54 , wherein the porous carrier is comprises at least one of alumina, silica, zirconia, clays, silicates, aluminates and mixtures thereof.  
     
     
         56 . The system of  claim 52 , wherein the monopropellant comprises a stabilizer.  
     
     
         57 . The system of  claim 56 , wherein the stabilizer comprises tin in the form of an alkali metal stannate.  
     
     
         58 . The system of  claim 56 , wherein the stabilizer comprises a phosphonic acid.