Ortho-Para Catalysis In Liquid-Hydrogen Production

Abstract

A series of selected or specially prepared catalysts were s tud ied fo r t heir abili ty to accelerate the ortho to para conversion of hydrogen . The results of t his st udy a re presented and the performance of various catalyst s are compared with t hat of chrom ic oxide on alu: mina pellets. An outstanding cata.lyst, u~supported hydrous J erric oxide g ra nules, was selected for further study and used 111 the liquefi ers of t he NatIOnal Burea u of Standards Cr yogenic Engineering Laboratory. One and one-half liters of t his catalyst has now bee n used to convert more t han 100,000 li ters of liquid hydrogen to 90 to 95 percent para at an average rate of about 235 liters of liquid per hour. There is to date no ev id ence of decrea se in effici ency with continued use.