Perchloryl fluoride was another of the extremely reactive and toxic oxidisers tested in the United States in the late 1950's. As in the other cases, it was found that the handling problems and safety risks outweighed the performance benefits. ClO3F is a colorless gas at atmospheric pressure and ambient temperature. The liquid is water-white. Perchloryl fluoride is normally supplied in 98 per cent concentration; moisture is limited to 0.02 weight per cent maximum. It is a moderately toxic, strongly oxidising agent. The mild sweetish odour is detectable at a concentration of 10 PPM in air. Perchloryl fluoride is permanently storable in common materials of construction. It is insensitive to detonation and mechanical shock. The anhydrous material is not corrosive; however, the presence of any moisture greatly increases the corrosiveness. There are several metals which are compatible with the "wet" oxidiser. There are a number of acceptable non-metals. Conventional lubricants should not be used.
Perchloryl fluoride may be prepared by the electrolysis of a mixture of sodium perchlorate (NaClO4) and hydrochloric acid (HF). 1959 production levels were very small; and the material had only recently become available in small commercial quantities at a price of $30 per kg. The projected price for large-scale production (5 million kg/year) was $ 3.30 per kg.
In January 1953 Rocketdyne commenced the REAP program to develop a number of improvements to the engines being developed for the Navaho and Atlas missiles. Among these was development of a special grade of kerosene suitable for rocket engines. Prior to that any number of rocket propellants derived from petroleum had been used. Goddard had begun with gasoline, and there were experimental engines powered by kerosene, diesel oil, paint thinner, or jet fuel kerosene JP-4 or JP-5. The wide variance in physical properties among fuels of the same class led to the identification of narrow-range petroleum fractions, embodied in 1954 in the standard US kerosene rocket fuel RP-1, covered by Military Specification MIL-R-25576. In Russia, similar specifications were developed for kerosene under the specifications T-1 and RG-1. The Russians also developed a compound of unknown formulation in the 1980's known as 'Sintin', or synthetic kerosene. Rocket propellant RP-1 is a straight-run kerosene fraction, which is subjected to further treatment, i.e., acid washing, sulphur dioxide extraction. Thus, unsaturated substances which polymerise in storage are removed, as are sulphur-containing hydrocarbons. Furthermore, in order to meet specification requirements of density, heat of combustion, and aromatic content, the kerosene must be obtained from crudes with a high naphthene content. RP-1 is an excellent solvent for many organic materials. The flash point is above 43 deg C. Above that temperature RP-1 will form explosive mixtures with air. The temperature range for explosive mixtures (rich limit) is 79 to 85 deg C. RP-1 is not so toxic as the JP series of fuels because of its lower aromatic content. In the United States, suitable kerosene fractions in 1960 were limited almost exclusively to the West Coast. The estimated 1956 United States production was 7700 tonnes, and the price was $0.05 per kg. By the 1980's it was typically $ 0.20 per kg. Russian formulations have typical densities of 0.82 to 0.85 g/cc, and even higher densities were achieved in the N1 and Soyuz 11A511U rockets by superchilling the fuel prior to loading.