THERMOCHROMATOGRAPHIC INVESTIGATION OF N-13 LABELED NITROUS GASES ANDOF FISSION NOBLE-GASES AT LOW-TEMPERATURES

A thermochromatographic device was developed which allows to study vol atile species with deposition temperatures as low as 88 K. With this d evice the adsorption behaviour of carrier free (NO)N-13, (NO2)N-13 and H(NO3)-N-13 as well as of 138,139Xe and 91Kr on solid materials were used: quartz, teflon, graphite, TiO2, V2O5/TiO2, and molecular sieve 5 A. From the experimentally measured deposition temperatures the differ ential molar adsorption enthalpies at zero coverage were determined. T he experiments clearly showed that thermochromatographic processes sti ll lead to well defined chromatographic peaks even at temperatures as low as 88 K and high gas flow rates of 11/min.