Rapid dispersion of oil slick in water is the precondition for oil biodegradation.Bentonite particles modified by surfactant were added into oily water mixture to form oil-mineral-aggregate(OMA) with oil droplets,which enhanced the oil dispersion and biodegradation rates.The impact of different types of modified bentonites on OMA formation efficiency was studied in the laboratory.The most effective CTAB modified bentonite was selected for oil biodegradation experiment.Petroleum degrading strains Micrococcus...