Isotopic densification of propellant

Abstract

A propellant and a propellant combination. In a preferred embodiment, the propellant includes a portion of an element and two isotopes of the element. The portion of the element is enriched with one of the isotopes and is adapted to being ionized. Preferably, the element is xenon. In another preferred embodiment, the present invention also provides a propellant combination that includes portions of two elements that are adapted to being combined. The portion of the first element includes two isotopes and is enriched in the first of the isotopes. Preferably the first element is fluorine, chlorine, boron, or bromine. Methods of using isotopically enriched propellants are provided in other preferred embodiments as well as mobile platforms (e.g. spacecraft) that are adapted to use isotopically enriched propellants.

1 . A propellant comprising: 
 a portion of an element;    a first isotope of the element; and    a second isotope of the element, the first and the second isotopes each having a natural abundance in the element, the portion of the element being enriched with the first isotope and being adapted to be ionized for use as the propellant.    
     
     
         2 . The propellant according to  claim 1 , further comprising the element including at least one of carbon, lithium, and xenon.  
     
     
         3 . A method of operating a mobile platform, comprising: 
 enriching a portion of an element with a first isotope of the element, the element having a second isotope, the first and the second isotope each having a natural abundance in the element;    ionizing the enriched portion of the element; and    using the portion of the element as a constituent of a propellant.    
     
     
         4 . The method according to  claim 3 , further comprising sizing a propellant tank based on the enriched portion of the element.  
     
     
         5 . The method according to  claim 3 , further comprising the enriching increasing a specific impulse of the enriched and ionized portion of the element.  
     
     
         6 . The method according to  claim 3 , further comprising the enriching densifying the propellant.  
     
     
         7 . The method according to  claim 3 , further comprising storing the enriched portion of the element on the mobile platform.  
     
     
         8 . The method according to  claim 3 , further comprising expelling the enriched and ionized portion of the element from the mobile platform to produce thrust.  
     
     
         9 . The method according to  claim 3 , further comprising determining an enrichment level for the propellant, the determining including a cost/benefit trade-off.  
     
     
         10 . A mobile platform comprising: 
 a propellant container sized and dimensioned to store a propellant, the propellant to include: 
 a portion of an element,  
 a first isotope of the element, and  
 a second isotope of the element, the first and the second isotopes each having a natural abundance in the element, the portion of the element being enriched with the first isotope; and  
   an engine communicating with the propellant container to receive the enriched propellant from the container and to ionize the propellant.    
     
     
         11 . The mobile platform according to  claim 10 , wherein the engine is a xenon electric propulsion engine.  
     
     
         12 . The mobile platform according to  claim 10 , further comprising being a geostationary satellite.  
     
     
         13 . A mobile platform comprising: 
 a propellant container to store a propellant, the propellant to include: 
 a portion of an element,  
 a first isotope of the element, and  
 a second isotope of the element, the first and the second isotopes each having a natural abundance in the element, the propellant container sized and dimensioned to store a first volume of the propellant with the isotopes in their natural abundances;  
   a rocket engine communicating with the propellant container to receive the propellant from the container and to ionize the propellant; and    a second volume of the propellant enriched in the first isotope and stored in the propellant container.    
     
     
         14 . The mobile platform according to  claim 13 , further comprising, the first volume being equal to the second volume and second volume of enriched propellant having more mass than the first volume of the propellant.  
     
     
         15 . A propellant combination, comprising: 
 a first portion of a first element;    a first isotope of the first element;    a second isotope of the first element, the first and the second isotopes each having a natural abundance in the first element, the first portion of the first element being enriched with the first isotope; and    a second portion of a second element, the first and the second portions being adapted to combine.    
     
     
         16 . The propellant combination according to  claim 15 , further comprising the first element being at least one of chlorine, boron, and bromine.  
     
     
         17 . A mobile platform comprising: 
 at least one propellant container sized and dimensioned to store a first propellant, the first propellant to include: 
 a portion of a first element,  
 a first isotope of the first element, and  
 a second isotope of the first element, the first and the second isotopes each having a natural abundance in the first element, the portion of the first element to be enriched with the first isotope;  
   the at least one propellant container being sized and dimensioned to store a second propellant, the propellants adapted to be combined; and    an engine communicating with the at least one propellant container to receive the combined propellants.    
     
     
         18 . A mobile platform comprising: 
 at least one propellant container sized and dimensioned to store a first propellant, the first propellant to include: 
 a portion of a first element,  
 a first isotope of the first element, and  
 a second isotope of the first element, the first and the second isotopes each having a natural abundance in the first element, the at least one propellant container being sized and dimensioned to store the first propellant with the isotopes in their natural abundances;  
   the at least one propellant container being sized and dimensioned to store a second propellant, the first and second propellants to be adapted to be combined;    an engine communicating with the at least one propellant container to receive the combined propellants; and    a second volume of the first propellant enriched in the second isotope and stored in the at least one propellant container.    
     
     
         19 . The mobile platform according to  claim 18 , wherein the first element is chlorine.  
     
     
         20 . The mobile platform according to  claim 18 , wherein the at least one propellant container is a casing.  
     
     
         21 . The mobile platform according to  claim 18 , wherein the at least one propellant container includes a first propellant tank for storing the first propellant and a second propellant tank for storing the second propellant.  
     
     
         22 . A method of operating a mobile platform, comprising: 
 enriching a first portion of a first element with a first isotope of the element, the first element having a second isotope, the first and the second isotope each having a natural abundance in the first element;    combining the enriched first portion of the first element with a second portion of a second element; and    using the combined portions to propel the mobile platform.    
     
     
         23 . The method according to  claim 22 , further comprising the first element being at least one of chlorine, boron, and bromine.