PRELIMINARY ASSESSMENT OF TIO2@PVP (POLYVINYLPYRROLIDONE) NANOCOMPOSITE FOR IFT REDUCTION AND WETTABILITY ALTERATION IN INDIANA LIMESTONE – EOR IMPLICATIONS

Abstract

The application of enhanced oil recovery (EOR) methods is inevitable to address the global demand for fossil fuels in the foreseeable future when oil and gas are a notable portion of the world energy basket. Over half of the global oil reserves occur in carbonate reservoirs, which make them a primary EOR target. Recently, the application of nanotechnology in the petroleum industry and particularly using nanoparticles (NP) as chemical EOR agnates has become one of the hot research topics. However, nano-EOR is still in its early stage of development and further research is required on different aspects of this subject. The main objective of this capstone project was to conduct a preliminary assessment of the effect of TiO2-coated polyvinylpyrrolidone (TiO2@PVP) on IFT reduction and wettability alteration in Indiana limestone. TiO2@PVP nanocomposite was used to prepare nanofluids (100, 250, 500, and 1000 ppm). The tested TiO2@PVP nanocomposite was characterized using Fourier-transform infrared spectroscopy (FTIR) and Transmission electron microscopy (TEM). The FTIR revealed the presence of C–O–C, C–C, Ti–O–C, and Ti–O groups in the nanocomposite. The TEM results also showed that the average size of nanocomposite is 77.4 nm ranging from 66.4 nm to 91.2 nm. The IFT and contact angle measurements were also conducted. Based on the experimental results, the minimum IFT was seen at 250 ppm (18.23 mN/m) compared to IFT in the absence of nanocomposite (91 mN/m). 250 ppm is considered the optimum concentration for the use of TiO2@PVP nanocomposite. The contact angle measurements revealed that the TiO2@PVP nanofluid can alter the wettability from oil-wet to water-wet state. Treatment of rock samples with 250 ppm nanofluid resulted in the highest contact angle reduction by 43.4%, reducing it from 107.8° to 61.0°. The contact angle results agreed with IFT results and confirmed that TiO2@PVP nanocomposite is a potentially proper EOR agent in carbonate reservoirs.