Physico-chemical studies of chemical, mineralogical and phase features of Darbaza clay and swelling agents of oil sludge have been carried out to study the multifunctional sorption properties of local bentonite clays. The contents of the mineralogical and organic part of oil sludge were determined with physicochemical studies. As a result, it was determined that paraffin-naphthenic and aromatic compounds predominate in the organic part and the compounds of silicon, calcium, aluminum and iron predominate in the mineral part. Carried out studies of the modification method of local bentonites with acidic and thermal treatment, which activate sorption properties, are due to the cation exchange of the initial elements of montmorillonite minerals.