Villegas Arcos Xilena, Blanco Mayorga Juliet Daniela, Chaves-Guerrero Arlex, Mercado Ronald
Grupo de Investigación en Fenómenos Interfaciales, Reología y Simulación de Transporte-FIRST, Universidad Industrial de Santander, Bucaramanga 680002, Colombia.
Grupo de Investigación en Recobro Mejorado-GRM, Universidad Industrial de Santander, Bucaramanga 680002, Colombia.
Materials (Basel). 2025 Mar 16;18(6):1305. doi: 10.3390/ma18061305.
The wettability of granular solids is a critical parameter in numerous industrial applications, including enhanced oil recovery, advanced material coatings, and nanotechnology. However, traditional methods for assessing wettability, such as contact angle measurements, face significant challenges when applied to heterogeneous or porous solids. This study proposes a rheological methodology as an alternative approach to determine the wettability of granular solids, focusing on bentonite clay modified via sodium dodecylbenzene sulfonate adsorption. Aqueous and oily suspensions of bentonite with varying degrees of hydrophobicity were characterized using viscosity measurements, oscillatory amplitude sweeps, and thixotropic recovery tests. For the system under study, a bentonite concentration of 8% ensures optimal rheological behavior. Furthermore, the adsorption isotherm provides a reliable means of determining varying degrees of solid coverage. The results demonstrated clear correlations between surface coverage and rheological behavior, with increasing hydrophobicity leading to reduced viscosity and viscoelasticity in aqueous systems and a shift toward Newtonian flow behavior in oily systems. These findings were supported by traditional contact angle measurements, which confirmed the relationship between surfactant adsorption and enhanced hydrophobicity. The proposed rheological methodology overcomes the limitations of conventional wettability assessments and provides a new approach for characterizing and optimizing the interfacial properties of particulate systems. This work has broad implications across industries such as petroleum, coatings, and material science, offering a novel pathway for designing systems with tailored wettability and flow characteristics.
粒状固体的润湿性是众多工业应用中的关键参数，包括提高石油采收率、先进材料涂层和纳米技术。然而，传统的润湿性评估方法，如接触角测量，在应用于非均质或多孔固体时面临重大挑战。本研究提出一种流变学方法作为确定粒状固体润湿性的替代方法，重点研究通过十二烷基苯磺酸钠吸附改性的膨润土。使用粘度测量、振荡振幅扫描和触变恢复测试对具有不同程度疏水性的膨润土水悬浮液和油悬浮液进行了表征。对于所研究的体系，8%的膨润土浓度可确保最佳流变行为。此外，吸附等温线提供了一种确定不同程度固体覆盖率的可靠方法。结果表明，表面覆盖率与流变行为之间存在明显的相关性，随着疏水性的增加，水体系中的粘度和粘弹性降低，油体系中的流动行为向牛顿流体转变。传统的接触角测量结果支持了这些发现，证实了表面活性剂吸附与增强疏水性之间的关系。所提出的流变学方法克服了传统润湿性评估的局限性，为表征和优化颗粒体系的界面性质提供了一种新方法。这项工作对石油、涂料和材料科学等行业具有广泛的意义，为设计具有定制润湿性和流动特性的体系提供了一条新途径。
