The ion exchange properties of humic acids prepared from oxidized young coals of the North-Bohemia coal field, the so-called oxyhumolites, were measured. A flow arrangement was used, i.e. separation of metals in columns packed with activated humic acids. Solutions containing only one metal (Pb2+, Cd2+, Cu2+, Zn2+, Ni2+, Ca2+, Mg2+ Co2+, Mn2+) and solutions containing two and more metals were tested. The penetrating capacities were measured for a number of metal ions under conditions emulating industrial applications of humate-based sorbents. Penetrating capacities are related to the total capacities estimated from measurements in a static system and a metal-binding model published previously, although they are, as expected, slightly lower.