ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Effect of pH, temperature, and salinity on the performance of ZnO/MgO nanofluid using analytical characterization with ImageJ and response surface methodology

Chunping Liu, Wanchun Zhao, and Zeeshan Ali Lashari

Daqing Oilfield Company, Limited, Daqing, People’s Republic of China

E-mail: zhaowanchun@nepu.edu.cn

Received: 16 October 2025  Accepted: 10 December 2025

Abstract:

Nanoparticles can increase sweep efficiency and mobilize residual oil from reservoir, and their application in enhanced oil recovery (EOR) has garnered considerable research interest. Nanofluids are one of the many nanotechnology-driven approaches that have shown promise in reservoir engineering; however, the durability of nanoparticles in saline conditions has a significant impact on performance in reservoir conditions. In this study, a Zinc oxide (ZnO) and Magnesium oxide (MgO) based nanofluid formed with Pure bore was developed and optimized to achieve minimal particle sedimentation and good colloidal stability under salinity conditions. ZnO and MgO nanoparticles were mixed with Pure bore solutions ranging from 0.10 to 0.50 wt%, and the experiments were performed in laboratory with NaCl (0.5–3.50 wt%). The viscosity, pH, and temperature of the nanofluid were measurements. Moreover, Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Elemental (EDX), and scanning electron microscope (SEM) were used to investigate the crystalline structure and elemental composition of the nanoparticles. The stability of the nanofluid was investigated using UV-spectroscopy and ImageJ based analysis. Analysis of variance (ANOVA), in conjunction with Response Surface Methodology (RSM), was used for statistical modeling and optimization. ZnO-based nanofluids exhibited better colloidal stability than their MgO-based counterparts. This is mainly because ZnO has more surface hydroxyl (–OH) groups, which improve hydrogen bonding with the carboxyl functional groups in Pure bore. The optimized formulation, which consisted of Pure bore (0.40 wt%), ZnO (0.50 wt%), and NaCl (3.50 wt%), exhibited outstanding stability with viscosity 34.8 cP at 50 °C and is anticipated to improve the efficiency of hydrocarbon recovery in low-salinity conditions.

Keywords: Pure bore; Magnesium oxide; Zinc oxide; Enhanced oil recovery; Low salinity; Response surface methodology; Central composite design

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-025-04595-3

Chemical Papers 80 (5) 4893–4911 (2026)