{"title":"Research and Development of a CO<sub>2</sub>-Responsive TMPDA-SDS-SiO<sub>2</sub> Gel System for Profile Control and Enhanced Oil Recovery.","authors":"Guojun Li, Meilong Fu, Jun Chen, Yuhao Zhu","doi":"10.3390/gels11090709","DOIUrl":null,"url":null,"abstract":"<p><p>A CO<sub>2</sub>-responsive TMPDA-SDS-SiO<sub>2</sub> gel system was developed and evaluated through formulation optimization, structural characterization, rheological testing, and core flooding experiments. The optimal formulation was identified as 7.39 wt% SDS, 1.69 wt% TMPDA, and 0.1 wt% SiO<sub>2</sub>, achieving post-CO<sub>2</sub> viscosities above 10<sup>3</sup>-10<sup>4</sup> mPa·s. Spectroscopic and microscopic analyses confirmed that CO<sub>2</sub> protonates TMPDA amine groups to form carbamate/bicarbonate species, which drive the micellar transformation into a wormlike network, thereby enhancing gelation and viscosity. Rheological tests showed severe shear-thinning behavior, excellent shear recovery, and reversible viscosity changes under alternating CO<sub>2</sub>/N<sub>2</sub> injection. The gel demonstrated rapid responsiveness, reaching stable viscosities within 8 min, and maintained good performance after 60 days of thermal aging at 90 °C and in high-salinity brines. Plugging tests in sand-packed tubes revealed that a permeability reduction of 98.9% could be achieved at 0.15 PV injection. In heterogeneous parallel core flooding experiments, the gel preferentially reduced high-permeability channel conductivity, improved sweep efficiency in low-permeability zones, and increased incremental oil recovery by 14.28-34.38% depending on the permeability contrast. These findings indicate that the CO<sub>2</sub>-responsive TMPDA-SDS-SiO<sub>2</sub> gel system offers promising potential as a novel smart blocking gel system for improving the effectiveness of CO<sub>2</sub> flooding in heterogeneous reservoirs.</p>","PeriodicalId":12506,"journal":{"name":"Gels","volume":"11 9","pages":""},"PeriodicalIF":5.3000,"publicationDate":"2025-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12469825/pdf/","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Gels","FirstCategoryId":"92","ListUrlMain":"https://doi.org/10.3390/gels11090709","RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"POLYMER SCIENCE","Score":null,"Total":0}
引用次数: 0
Abstract
A CO2-responsive TMPDA-SDS-SiO2 gel system was developed and evaluated through formulation optimization, structural characterization, rheological testing, and core flooding experiments. The optimal formulation was identified as 7.39 wt% SDS, 1.69 wt% TMPDA, and 0.1 wt% SiO2, achieving post-CO2 viscosities above 103-104 mPa·s. Spectroscopic and microscopic analyses confirmed that CO2 protonates TMPDA amine groups to form carbamate/bicarbonate species, which drive the micellar transformation into a wormlike network, thereby enhancing gelation and viscosity. Rheological tests showed severe shear-thinning behavior, excellent shear recovery, and reversible viscosity changes under alternating CO2/N2 injection. The gel demonstrated rapid responsiveness, reaching stable viscosities within 8 min, and maintained good performance after 60 days of thermal aging at 90 °C and in high-salinity brines. Plugging tests in sand-packed tubes revealed that a permeability reduction of 98.9% could be achieved at 0.15 PV injection. In heterogeneous parallel core flooding experiments, the gel preferentially reduced high-permeability channel conductivity, improved sweep efficiency in low-permeability zones, and increased incremental oil recovery by 14.28-34.38% depending on the permeability contrast. These findings indicate that the CO2-responsive TMPDA-SDS-SiO2 gel system offers promising potential as a novel smart blocking gel system for improving the effectiveness of CO2 flooding in heterogeneous reservoirs.
期刊介绍:
The journal Gels (ISSN 2310-2861) is an international, open access journal on physical (supramolecular) and chemical gel-based materials. Our aim is to encourage scientists to publish their experimental and theoretical results in as much detail as possible. Therefore, there is no restriction on the maximum length of the papers, and full experimental details must be provided so that the results can be reproduced. Short communications, full research papers and review papers are accepted formats for the preparation of the manuscripts.
Gels aims to serve as a reference journal with a focus on gel materials for researchers working in both academia and industry. Therefore, papers demonstrating practical applications of these materials are particularly welcome. Occasionally, invited contributions (i.e., original research and review articles) on emerging issues and high-tech applications of gels are published as special issues.