Gao Fengfeng
The Department of Materials and Chemical Engineering, Zibo Vocational Institute, Zibo, 255300, China.
J Mol Graph Model. 2025 Jan;134:108897. doi: 10.1016/j.jmgm.2024.108897. Epub 2024 Oct 26.
Understanding the adsorption behavior of heavy oil components on reservoir solids is crucial for improving oil recovery, yet the molecular mechanism remains unclear. This study used molecular dynamics simulations to explore the adsorption kinetics and thermodynamics of asphaltene molecules on silica surfaces. The adsorption process was divided into three stages: free, adsorption, and equilibrium. In the adsorption stage, asphaltenes must pass through two dense hydration layers and adhere to the silica surface in a flat configuration. Carboxyl groups increase asphaltene hydrophilicity, raising interaction energy with water molecules and hindering adsorption. In addition, two distinct hydration layers of water molecules on the silica surface. The first hydration layer, with a peak density of 2000 kg m, was located around 0.6 nm from the surface, driven by hydrogen bonding between Si-OH groups and water molecules. The second layer, found at 1.44-1.80 nm, had a lower density of 1200 kg m, formed through hydrogen bonding between water molecules. This study aims to enhance the understanding of the physicochemical mechanisms governing oil droplet adsorption on silica surfaces, potentially informing the design of improved oil recovery strategies.
了解重油成分在储层固体上的吸附行为对于提高原油采收率至关重要，但其分子机制仍不清楚。本研究采用分子动力学模拟方法，探讨沥青质分子在二氧化硅表面的吸附动力学和热力学。吸附过程分为三个阶段：自由阶段、吸附阶段和平衡阶段。在吸附阶段，沥青质必须穿过两个致密的水化层，并以扁平构型附着在二氧化硅表面。羧基增加了沥青质的亲水性，提高了与水分子的相互作用能，从而阻碍吸附。此外，二氧化硅表面存在两个不同的水分子水化层。第一个水化层的峰值密度为2000 kg/m³，位于距表面约0.6 nm处，由Si-OH基团与水分子之间的氢键驱动。第二层位于1.44 - 1.80 nm处，密度较低，为1200 kg/m³，通过水分子之间的氢键形成。本研究旨在加深对油滴在二氧化硅表面吸附的物理化学机制的理解，可能为改进原油采收策略的设计提供参考。
