Thermochromatography of carrier-free lead in quartz columns with hydrogen and argon as carrier gases

The thermochromatography of lead on quartz surfaces was studied over a broad range of the experimental parameters gas flow rate and heating time. The carrier gases argon and hydrogen were used, although in both cases elemental lead was applied to the chromatographic system, from the experimentally determined deposition temperatures very different adsorption enthalpies ΔHsub(a)0 of -498 and -222 kJ mol-1 and adsorption entropies ΔSsub(a)0 of -427 and -222 J mol-1 K-1, respectively, were obtained for lead in the two carrier gases argon and hydrogen. (orig.)