Oxidizers, propellant hydrazinium nitrate

A number of other materials have received attention as potential oxidizers for propellant use, but to date have found little actual use. They include hydroxylammonium nitrate (HAN), hydroxylammonium perchlorate (HAP), hydrazinium nitrate (HN), hydra-zinium perchlorate (HP), and hexanitroiso-wurtzitane (CL-20). 

Ionic liquids should also be very suitable for use as monopropellants, but the salts used must contain either the oxidizer and fuel combined, or salt mixtures which contain both oxidizing and reducing salts. Since these mixtures are homogeneous systems which contain both the oxidizer and fuel, they can be labeled as monopropellants, just as hydrazine is. Particularly interesting are salt mixtures which are less toxic and have a lower vapor pressure than hydrazine. Such mixtures are also known as green propellants . Suitable anions are the nitrate or dinitramide ions [58], A combination which has already been studied intensively as an oxidizer is the HAN, hydroxylammonium nitrate system. ADN, ammonium nitrate (AN) and hydrazinium nitrate (HN) have also been investigated. As fuels, hydroxylammonium azide (HAA), ammonium azide (AA) or hydrazinium azide (HA) may be appropriate. As a rule, these salt mixtures are not used as pure substances on safety grounds, but with 20 or 40% water added they then decompose catalytically in an exothermic reaction. Table 9.7 shows the dependence of the calculated specific impulses on the water content for such salt mixtures. 

A number of other materials have received (HAP), hydrazinium nitrate (HN), and hydra-attention as potential oxidizers for propellant zinium perchlorate (HP). 

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