Hydroxylammonium nitrate monopropellant with burn rate modifier
View Patent ↗A monopropellant includes 30-70% by weight of an oxidizer including hydroxylammonium nitrate, 5-50% by weight of a fuel, and a burn rate modifier in a non-zero amount of up to 3% by weight. The burn rate modifier can be selected from vanadium salts, iron salts, and combinations thereof. The monopropellant is a stable liquid between −20 C and 100 C at ambient pressure.
1. A monopropellant comprising: 30-70% by weight of an oxidizer including hydroxylammonium nitrate; 5-50% by weight of a fuel; an amount, A1, by molar fraction of at least one stabilizer; and an amount, A2, by molar fraction of a burn rate modifier selected from the group consisting of vanadium salts, iron salts, and combinations thereof, wherein a ratio of A1 to A2 is greater than 1.0 to sustain combustion upon torch ignition in air at 1 atm pressure.
2. The monopropellant as recited in claim 1 , wherein the ratio is between 7 and 35.
3. The monopropellant as recited in claim 1 , wherein the burn rate modifier includes the vanadium salt.
4. The monopropellant as recited in claim 2 , wherein the vanadium salt is selected from the group consisting of vanadium pentoxide, ammonium metavanadate, vanadyl acetylacetonate, vanadyl sulfate, and combinations thereof.
5. The monopropellant as recited in claim 1 , wherein the burn rate modifier includes the iron salt.
6. The monopropellant as recited in claim 5 , wherein the iron salt is iron nitrate.
7. The monopropellant as recited in claim 1 , wherein the fuel includes at least one of methanol, ethanol, and glycine, the at least one stabilizer includes at least one chelating agent, and the burn rate modifier includes the vanadium salt.