The Effect Of Electrolytes To The Performance of PolyoxyBased Surfactant to Reduce the IFT

Abstrak

The use of surfactant in chemical enhanced oil recovery has been recognized to have a great role to extract the trapped oil from the reservoir. The ability of surfactant to reduce the interfacial tension between oil and water is affected by the characteristic of brine reservoir as well as the targeted crude oil. Brine composition is dominated by the presence of natrium chloride that represent as salinity, followed by the presence of calcium and magnesium. It is therefore, the present study investigates the influence of salinity and hardness to the performance of polyoxy-based surfactant to decrease the interfacial tension of oil and water. Polyoxy-based nonionic surfactants were analyzed by measuring the interfacial tension, and filtration rasio calculation. The results showed that the optimum condition of brine which create the lowest interfacial tension was at the range of 5000 - 30.000 ppm salinity. The increasing of hardness component calcium and magnesium was lowering the IFT value of oil and water. However, in the presence of salinity at 20.000 ppm, the effect of hardness increased the IFT with the increasing of hardness concentration. Filtration evaluation showed that the filtration rasio of surfactant was not affected by the saline brine concentration although there is indication of size exclusion due to the higher time interval between certain volume of surfactant solution at higher saline. These results indicated that brine salinity as well as hardness concentration are having positive effect to the IFT of oil and water, whereas the filtration rasio of polyoxy-based surfactant is not affected by the concentration of electrolytes in the brine.