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A comprehensive theoretical and experimental study of the adsorption of water and methanol molecules onto the active centres (carboxy and phenol groups) of a graphitised carbon black surface is reported. It was shown that the micro-clusters formed during the adsorption process possess a cyclic structure involving four to five molecules, similar to that found earlier in liquid water and at the silver iodide surface. Analysis of the structure and energetics of these clusters showed that their formation is governed primarily by the formation of hydrogen bonds, whilst energetic effects related to the change in the state of motion of the molecules during their adsorption also play a certain role. It was shown that the generalised Langmuir equation derived from molecular statistical considerations is capable of providing a good description of the experimental isotherm over a wide surface coverage range. It also provides a consistent interpretation of the data on the structural and energetic characteristics of the adsorption systems studied as obtained by gas chromatographic and quantum chemical methods.

Physicochemical methods were used for a comprehensive study of the structural/sorption properties of the natural mineral shungite. It was shown that the composite structure of the mineral determines its main physicochemical characteristics. The isosteric heat of adsorption of water vapour was estimated by calorimetric methods as 70 kJ/mol. This value corresponds to the interaction of water molecules with the vicinal hydroxy groups of the silica constituent of shungite; adsorption heats with values in the range 40–45 kJ/mol are characteristic of the carbon constituent of the sorbent. The heat of adsorption of benzene onto shungite was higher than that for hexane adsorption onto the mineral, indicating that specific interaction occurs between the benzene molecules and the active centres which exist on both the carbon and silica constituents of the mineral. It was shown that the adsorption parameters of shungite with respect to organic compounds which dissociate in an anionic manner suggest that the mineral could be applied as a filtering material with a sorptive action for water cleansing.