Experimental evaluation of surface treated nanoparticles and their effect on wettability alteration of carbonate surfaces and oil-brine interfacial tension

The alteration of rock surface wettability and the reduction of oil/brine interfacial tension enhances oil recovery from the reservoir. Most of the carbonate rock reservoirs around the world are oil-wet and changing their wettability may enhance oil recovery. Moreover, nanoparticles have presented a promising potential in enhanced oil recovery applications. An experimental study of contact angle changes upon exposure to nanoparticles on carbonate surfaces that are dispersed in brine solution has been conducted using various nanoparticle solutions, some of which were in-house synthesized. Also, interfacial tension measurements and calculations were implemented using the pendant drop method to study the effect of the invading nanoparticles solution. Nanoparticle concentrations were varied and progress was monitored with time. Effects of nanoparticle size, grafting coverage and mixed chemicals as well as observations are discussed. Two hypotheses were proposed for the wettability alteration mechanisms.Petroleum and Geosystems Engineerin