Yang Xiong^1,2, Jianxin Liu^1,2,*, Xianhao Yi², Bangyan Xiao², Dan Wu², Biao Wu², Chunyu Gao²

Energy Engineering, Vol.121, No.7, pp. 1759-1780, 2024, DOI:10.32604/ee.2024.048536 - 11 June 2024

Abstract In the heterogeneous reservoirs, CO₂ flooding easily leads to CO₂ gas channeling, which can seriously affect sweeping efficiency and reduce oil recovery. After thoroughly investigating the advantages and shortcomings of various CO₂ plugging technologies, this paper focuses on the feasibility of improving conventional water-alternating gas (WAG) through CO₂-responsive gel materials. Based on the different chemical reaction mechanisms between the unique chemical structure and CO₂, changes in the material’s physical and chemical properties can respond to CO₂. The feasibility of utilizing these property changes for CO₂-responsive plugging is explored. Various CO₂-responsive gels and gel nanoparticles have been extensively researched in More >

Weishan Tang, Xin Feng, Caiyun Lin, Xiaoping Rao^*

Journal of Renewable Materials, Vol.11, No.2, pp. 523-538, 2023, DOI:10.32604/jrm.2022.022809 - 22 September 2022

Abstract Environment friendly and intelligent surfactants have attracted great attention in recent years. A bio-based CO₂ responsive surfactant rosin acid dimaleimide choline (R-BMI-C) with an extremely rigid skeleton was prepared using rosin and choline as raw materials by Diels-Alder addition reaction and acid-base neutralization reactions. Its structure was confirmed by IR and ¹H NMR spectra. The foams’ properties of R-BMI-C could be adjusted by bubbling CO₂/N₂ to change the structure of the surfactant. At pH 10.4, R-BMI-C forms an unstable foam with a half-life of 1.5 h. When the pH was reduced to 7.4 by bubbling CO₂, R-BMI-C… More > Graphic Abstract