Structural characteristics of a carbon adsorbent and influence of organic solvents on interfacial water

Different treatments (suspending in water, drying, freezing by liquid nitrogen, de-ashing, oxidation by H2O2, reduction by H2, and some combinations of these methods) of activated carbon Norit R 0.8 Extra lead to changes in micropores to a greater extent than mesopores. Influence of polar (CD3CN, (CD3)2CO and (CD3)2SO) and nonpolar (CCl4, CDCl3 and C6D6) solvents on the structure of interfacial water pre-adsorbed on the carbon adsorbent was studied by 1H NMR spectroscopy with freezing-out of the adsorbed water at 180 K<T<273 K and modelled by using quantum chemistry methods with consideration for the solvation effects. It was found that water interaction with the carbon surfaces depends strongly on the properties of solvents, which can remove a major (by nonpolar solvents insoluble in water) or minor (by polar solvents soluble in water) portion of water from narrow micropores to larger pores.