This page no longer updated from 31 October 2001. Latest version can be found at www.astronautix.com

astronautix.com Hydrazine






Fuel: Hydrazine. Fuel Density: 1.01 g/cc. Fuel Freezing Point: 2.00 deg C. Fuel Boiling Point: 113.00 deg C.

Hydrazine (N2H4) found early use as a fuel, but it was quickly replaced by UDMH. It is still used as a monopropellant for satellite station-keeping motors. Hydrazine marketed for rocket propellant contains a minimum of 97 per cent N2H4, the other constituent being primarily water. Hydrazine is a clear, water-white, hygroscopic liquid. The solid is white. Hydrazine a toxic, flammable caustic liquid and a strong reducing agent. Its odour is similar that of ammonia, though less strong. It is slightly soluble in ammonia and methyl-amine. It is soluble in water, methanol, ethanol, UDMH, and ethylenediamine. Hydrazine is manufactured by the Raschig process, which involves the oxidation of ammonia to chloramine, either indirectly with aqueous sodium hypochlorite or directly with chlorine, and subsequent reaction of chloramine with excess ammonia. Raw materials include caustic, ammonia, and chlorine; these are high-tonnage, heavy chemicals. The cost of anhydrous hydrazine in drum quantities in 1959 was $ 7.00 per kg. The projected price, based on large-scale commercial production, was expected to be $ 1.00 per kg. Due to environmental regulations, by 1990 NASA was paying $ 17.00 per kg.

Engines Using Hydrazine

Eng-engineslink Thrust(vac)-kgf Thrust(vac)-kN Isp-sec Isp (sea level)-sec Designed for Status
MR-508 LPHA 0 0.00 502   Upper Stages In Production
MR-502 IMPEHT 0 0.00 304   Upper Stages In Production
REA 10 0 0.00     Upper Stages In Production
MR-103 0 0.00 227   Upper Stages In Production
REA 17-6 0 0.00     Upper Stages In Production
REA 39-2 0 0.00     Upper Stages In Production
MR-111 0   229   Upper Stages In Production
REA 17-12 0 0.00     Upper Stages In Production
DOT-5 1 0.01 230   Upper Stages In Production
DOK-10 1 0.01 229   Upper Stages In Production
REA 16 2 0.02     Upper Stages In Production
MR-50 2 0.02 228   Upper Stages In Production
DOT-25 3 0.03 235   Upper Stages In Production
MR-106 3 0.03 232   Upper Stages In Production
REA 22-5 5 0.05     Upper Stages In Production
DOK-50 5 0.05 229   Upper Stages In Production
REA 22-2 9 0.09     Upper Stages In Production
MRE-15/OMV 9 0.09 225   Upper Stages In Production
REA 22-16 13 0.13     Upper Stages In Production
REA 22-17 18 0.18     Upper Stages In Production
MR-107 26 0.26 236   Upper Stages In Production
MR-104 45   239   Upper Stages In Production
REA 20-4 56 0.56     Upper Stages In Production


Back to Index
Last update 3 May 2001.
Contact Mark Wade with any corrections or comments.
Conditions for use of drawings, pictures, or other materials from this site..
© Mark Wade, 2001 .