Probing of the hydrated cation bridges in the oil/brine/silica system via atomic force microscopy and molecular dynamics simulation

Hu, Yong; Chu, Zhongzhong; Dai, Caili; Wang, Fengchao; Ren, Hao; Xu, Jinkai; Wu, Yining

doi:10.1016/j.fuel.2021.121666

Cited by 13 publications

(10 citation statements)

References 41 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…effect describes the chemical interactions between oil and the rock in the oil/brine/rock system, which are caused by divalent cations. 66 In particular, divalent cations (e.g., Ca 2+ and Mg 2+ ) form hydrated cations (e.g., [Ca(H 2 O) 6 ] 2+ and [Mg-(H 2 O) 6 ] 2+ ) in the water film. These hydrated cations can bridge the negatively charged polar components (e.g., carboxyl, hydroxyl, and phenols) on the crude oil surface and the negatively charged sites on the rock surface (e.g., >SiO − and >AlO − ), providing attraction between rock and oil surfaces.…”

Section: Resultsmentioning

confidence: 99%

“…The calcium ion-bridging effect can explain why the CA does not change with pH in CaCl 2 solutions in the water film. The ion-bridging effect describes the chemical interactions between oil and the rock in the oil/brine/rock system, which are caused by divalent cations . In particular, divalent cations (e.g., Ca 2+ and Mg 2+ ) form hydrated cations (e.g., [Ca(H 2 O) 6 ] 2+ and [Mg(H 2 O) 6 ] 2+ ) in the water film.…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Effects of Electro-Oxidation Process on Tight-Rock Wettability and Imbibition Oil Recovery

et al. 2022

View full text Add to dashboard Cite

Oil and gas industry has faced significant operational, economic, and environmental challenges in recycling produced water. The treatment of produced water is highly researched, but few studies have evaluated the performance of treated produced water when used for hydraulic fracturing and enhanced oil recovery (EOR) operations. In this study, we treated various aqueous solutions, including synthetic formation brine (FB), sodium chloride (NaCl), calcium chloride (CaCl2), and sodium sulfate (Na2SO4), using an electro-oxidation (EO) process. The brine properties, including density, surface tension (ST), oil–water interfacial tension (IFT), viscosity, and pH, were compared before and after the treatment. Then, we conducted systematic contact-angle (CA) measurements and spontaneous imbibition tests using treated and untreated brine to study the effects of water treatment on rock–fluid interactions and its impact on oil recovery. The experimental results show that the effect of the EO process on ST, density, viscosity, and IFT was insignificant. However, the CA results show that the treated FB, NaCl, and Na2SO4 solutions exhibit stronger wetting characteristics compared with the untreated ones, while the treated CaCl2 solution exhibit weaker wetting characteristics compared with the untreated ones. We hypothesized that the change in the wetting characteristics was due to the generated oxidants from the EO process. We added OH–, H+, hydrogen peroxide (H2O2), and sodium hypochlorite (NaOCl) into untreated brine to test this hypothesis and monitored the CA variations. The results suggest that H2O2 and OH– can alter the wettability to more water-wet conditions in the NaCl solution but not in the CaCl2 solution. Furthermore, NaOCl results in wettability alteration to more oil-wet conditions in NaCl and CaCl2 solutions. The change in wettability to more water-wet conditions is mainly the result of the oxidation of dissolved organic matters, and the change to more oil-wet conditions is the result of the dissolution of high-valence cations, causing the cation bridging effect.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Effects of Electro-Oxidation Process on Tight-Rock Wettability and Imbibition Oil Recovery

et al. 2022

View full text Add to dashboard Cite

show abstract

“…The force fields parameters used in this study are summarized in Table S1 in the Supporting Information. These force fields have been used extensively to probe the interfacial properties of hydrocarbons and surfactants on a variety of solid surfaces, including silicious surfaces and pores, and validated against experimental characterizations. ,− Further, qualitative comparisons have been made between the simulations and the experiments throughout this work, and qualitative agreements in the aggregation behavior indicate the validity and compatibility of the used force fields.…”

Section: Methodsmentioning

confidence: 93%

Structure and Shape of Surface-Mediated Assembly of Surfactants

et al. 2021

View full text Add to dashboard Cite

Achieving controls on the self-assembly of cationic and block copolymer micelles has significant implications for advancing novel material systems for energy, environmental, and biological applications and for tuning fluid flow behavior in subsurface geologic environments. While it is known that the aggregation of micelles is influenced by the composition of the surrounding fluid, the influence of a solid interface has been less explored. In this study, we probe the organization of cetyltrimethylammonium bromide (CTAB) micelles in the absence and presence of the Pluronic P123 block copolymer and quartz substrate using transmission and grazing-incidence small-angle X-ray scattering measurements and classical molecular dynamics (MD) simulations. In the absence of the quartz interface, CTAB with and without P123 molecules assemble as ellipsoid core–shell micelles. Densification of the core on adding P123 is noted from the decrease in the core radius from 15.9 to 14.6 Å. The presence of a quartz substrate causes the micelles to elongate, which is noted by the emergence of a power-law slope in the low q region (<0.02 Å–1). Moreover, in the presence of both P123 and the quartz substrate, the micelle shape changes from ellipsoid core–shell to cylindrical core–shell, and a significantly higher number of aggregates are formed. The higher number of aggregates, and faster aggregation kinetics are linked to the organization of the solvent structures as noted from the MD simulations. These findings demonstrate the effects of adding a block copolymer and including a quartz substrate on the self-assembly of cationic (CTAB) micelles, which can be used to inform the design of functional material systems that harness surfactant chemistries.

show abstract

“…In addition, compared with Na + , the number of hydrogen bonds at the oil−brine interface was higher in the presence of Ca 2+ . 39,4039,40 It thus suggests that these ions may play a crucial role in oil displacement.…”

Section: Introductionmentioning

confidence: 99%

“…The hydrophilicity of the mica surface was found to be stronger with increasing NaCl concentration between 0.01 and 1 M, as reported by Liu et al The effects of the ion species on wettability have also been assessed. Mugele et al constructed an oil–salt solution–rock system, where the wettability of rocks under different ionic conditions was investigated. , Divalent or trivalent cations, such as Ca 2+ , Mg 2+ , and Al 3+ , tend to contact with the sandstone, altering the rock’s wettability. , Some researchers used molecular dynamics simulation methods to investigate the hydration ability of salt ions in brine. High valence cations had a stronger hydration capacity due to their stronger charge and could attract more water molecules to form hydrated cations with larger hydration radii.…”

Section: Introductionmentioning

confidence: 99%

Cation-Dependent Oil–Rock Interactions in Nanopores: Insights from Core Flooding Experiments and Molecular Dynamics Simulations

Wu,

Huang,

et al. 2023

Energy Fuels

Self Cite

View full text Add to dashboard Cite

A large amount of crude oil still adheres to the rock surface after water flooding in low-permeability reservoirs. Cations in the formation water were assumed to play a crucial role in crude oil adhesion. However, it lacks systematic investigation, and the mechanism remains unclear. In this work, the role of cations in these oil–rock interactions is investigated by performing water flooding experiments and molecular dynamics simulations. Results show that Ca2+ has a significant impact on the injection pressure and the oil recovery than Na+. The oil recovery of cores initially saturated by CaCl2 solution (39.02–47.48%) was lower than those saturated by NaCl solution (51.78–54.96%). It was found that the hydrated cations accumulate on the negatively charged rock surface to form a brine layer. The interaction energy between crude oil and rock surface was 1.7 times 0.5 M NaCl (−14.2 × 103 kJ·mol–1) when the brine layer contained 0.5 M CaCl2 (−24.2 × 103 kJ·mol–1), leading to the strong adhesion of crude oil. Thus, the amount of residual oil was higher in the presence of Ca2+ after water flooding. With the increase in Ca2+ concentration, the adhesion of crude oil became stronger, significantly reducing the efficiency of water flooding.

show abstract

Probing of the hydrated cation bridges in the oil/brine/silica system via atomic force microscopy and molecular dynamics simulation

Cited by 13 publications

References 41 publications

Effects of Electro-Oxidation Process on Tight-Rock Wettability and Imbibition Oil Recovery

Effects of Electro-Oxidation Process on Tight-Rock Wettability and Imbibition Oil Recovery

Structure and Shape of Surface-Mediated Assembly of Surfactants

Cation-Dependent Oil–Rock Interactions in Nanopores: Insights from Core Flooding Experiments and Molecular Dynamics Simulations

Contact Info

Product

Resources

About