zeta potential; carbonaceous materials; influence of oxygen content

The zeta potential of different kinds of carbonaceous materials was studied with respect to the content of oxygen. Samples of activated carbon, sub-bituminous, bituminous and oxidative altered bituminous coal were used. It was found, that zeta potential of coal samples decreases to more negative values with increasing native amount of oxygen. This trend was confirmed on samples of partially oxidized coal, for which the zeta potential decreases with increasing temperature of oxidation and increasing amount of chemisorbed oxygen. Activated carbon was the only exception found in the range of studied materials. Its zeta potential was lower then expected and did not correspond with the content of oxygen.

The zeta potential of different kinds of carbonaceous materials was studied with respect to the content of oxygen. Samples of activated carbon, sub-bituminous, bituminous and oxidative altered bituminous coal were used. It was found, that zeta potential of coal samples decreases to more negative values with increasing native amount of oxygen. This trend was confirmed on samples of partially oxidized coal, for which the zeta potential decreases with increasing temperature of oxidation and increasing amount of chemisorbed oxygen. Activated carbon was the only exception found in the range of studied materials. Its zeta potential was lower then expected and did not correspond with the content of oxygen.