Influence of Unipolar Corona Discharge Parameters on the Efficiency of Separation of Oil-Water Emulsions by Cellulose Acetate Membranes

The influence of the parameters of unipolar corona discharge (treatment time, voltage) on the productivity and selectivity of the separation of model Devonian oil-based oil-in-water emulsions using cellulose acetate (CA) membranes with a pore size of 0.2 mu m has been studied. The concentrations of oil products in the model emulsion, actual formation water, and the filtrates were determined. The values of treatment time and membrane coronation voltage of 5 min and 15 kV, respectively, at which the highest flux of 20 dm(3)/(m(2) h) and a 99.3% efficiency of removal of hydrocarbons from the oil-water emulsion are achieved, have been determined. The increase in flux is due to an increase in the porosity of the filters from 65.8 to 83.6%, and greater efficiency is achieved as a result of chemical restructuring of the membrane surface. By the sessile drop method, enhancement of the surface wettability of a CA filter treated with a corona discharge (U = 15 kV and tau = 5 min), viz., a decrease in the contact angle from 72.5 degrees to 64.6 degrees, has been revealed According to electrophoretic light scattering data, the filtrate of the modified membrane has a lower aggregative stability and contains smaller particles compared to the untreated filter. The efficiency of salinity reduction in the formation water using a membrane treated with a corona discharge at U = 15 kV and tau = 5 min was 99.2%.