Effect of nano silica particles on Interfacial Tension (IFT) and mobility control of natural surfactant (Cedr Extraction) solution in enhanced oil recovery process by nano - surfactant flooding

Natural surfactant is a new kind of surfactants which has been introduced in recent years in petroleum industry. It is cheap, abundant and environmental friendly. On the other hand, nano particles have received increasing attention in upstream industry in the last decade. In this communication, Cedr Extraction (CE) as natural surfactant and nano silica were used. The influence of CE and nano particles on Interfacial Tension (IFT) of aqueous phase was studied using Pendant Drop method. The effect of nano particles on mobility control was then investigated using the results of core flooding. By increasing the surfactant concentration from 0 to 10 wt%, it was observed that the IFT of kerosene and aqueous phase reduces from 35 to 11.9 mN/m; increasing the nano silica concentration from 0 to 2500 ppm causes the reduction in IFT value from 15.5 to 13 mN/m. Using pH method for investigating the CMC point of different concentrations of CE solution indicates that 5 wt% of CE in 100,000 ppm brine represents the CMC point. Repeating the above methods for different concentrations of nano silica in 5 wt% of CE solution shows that 1000 ppm of nano silica represents the CMC point. Adding nano silica causes increasing oil recovery from 53% (by flooding with CE solution) to 74%, in sandstone core.