Science

III. THE DEVELOPMENT OF INDUSTRIAL-SCALE LIQUIFIED HYDROGEN

III.A. Define the Problem and Research the Background

Liquid hydrogen has two isomeric forms at cryogenic temperatures: orthohydrogen and parahydrogen. Ordinary hydrogen liquifies at a ratio of 75% orthohydrogen to 25% parahydrogen. Over time, ordinary liquid hydrogen transforms to 99.8% parahydrogen in an exothermic reaction from orthohydrogen.[Citation11] As a result, ordinary liquid hydrogen/deuterium evaporates at a rate up to 20%/day until all the orthohydrogen exotherms to parahydrogen. The two isomers of hydrogen were known at the time of the project, but an effective catalyst to convert the orthohydrogen to parahydrogen was not known, despite active work on catalysts.[Citation12] Because of this, a large amount of work had to be performed to overcome the exothermic reaction and protect the precious liquified deuterium. This included the design, construction, and use of helium refrigerators. [An effective catalyst for volume production of parahydrogen was discovered by the National Bureau of Standards (NBS) in 1953, after Mike was detonated.][Citation13] Today, a mere 1% loss is considered acceptable.[Citation15]