@article{Liu2023, 
author = {Yang Liu and Hong-Jun Zhang and Dao-Yi Zhu and Zi-Yuan Wang and Jun-Hui Qin and Qi Zhao and Yu-Heng Zhao and Ji-Rui Hou},
title = {Effect of nano TiO2 and SiO2 on gelation performance of HPAM/PEI gels for high-temperature reservoir conformance improvement},
year = {2023},
journal = {Petroleum Science},
volume = {20},
number = {6},
pages = {3819-3829},
keywords = {Nano-TiO2, Nano-SiO2, Gel strength, Polymer gel, High-temperature reservoirs},
url = {https://www.sciopen.com/article/10.1016/j.petsci.2023.07.005},
doi = {10.1016/j.petsci.2023.07.005},
abstract = {Nanoparticles have been widely used in polymer gel systems in recent years to improve gelation performance under high-temperature reservoir conditions. However, different types of nanoparticles have different effects on their gelation performance, which has been little researched. In this study, the high-temperature gelation performance, chemical structure, and microstructure of polymer gels prepared from two nanomaterials (i.e., nano-SiO2 and nano-TiO2) were measured. The conventional HPAM/PEI polymer gel system was employed as the control sample. Results showed that the addition of nano-TiO2 could significantly enhance the gel strength of HPAM/PEI gel at 80 ℃. The gel strength of the enhanced HPAM/PEI gel with 0.1 wt% nano-TiO2 could reach grade I. The system also had excellent high-temperature stability at 150 ℃. The enhanced HPAM/PEI gel with 0.02 wt% nano-TiO2 reached the maximum gel strength at 150 ℃ with a storage modulus (G′) of 15 Pa, which can meet the need for efficient plugging. However, the nano-SiO2 enhanced HPAM/PEI polymer gel system showed weaker gel strength than that with nano-TiO2 at both 80 and 150 ℃ with G′ lower than 5 Pa. Microstructures showed that the nano-TiO2 enhanced HPAM/PEI gel had denser three-dimensional (3D) mesh structures, which makes the nano-TiO2 enhanced HPAM/PEI gel more firmly bound to water. The FT-IR results also confirmed that the chemical structure of the nano-TiO2 enhanced HPAM/PEI gel was more thermally stable than nano-SiO2 since there was a large amount of –OH groups on the structure surface. Therefore, nano-TiO2 was more suitable as the reinforcing material for HPAM/PEI gels for high-temperature petroleum reservoir conformance improvement.}
}