(522e) Development and Characterization of Adsorption and Desorption of Polymers from Mesoporous Materials with Application to Controlled Release of Inhibitors in Oil Production

Asphaltene precipitation poses a significant challenge in the oil and gas industry, leading to reduced production, equipment damage and even formation damage in some wells. To prevent precipitation and/or deposition of asphaltenes, asphaltene inhibitors (AI) are injected into the production well (so called squeeze treatment) more frequently than desired with great cost. Thus, there is great interest in designing controlled release systems with nanoparticles, such as mesoporous silica. Currently, there is no effective method to inhibit asphaltenes over time scales on the order of a year.

Herein, we developed and characterized an AI loaded porous silica that provided sustained release of the selected AI in a commonly used solvent, xylene. The materials were characterized using various techniques including scanning electron microscopy (SEM), nitrogen adsorption-desorption isotherms, dynamic light scattering, and zeta-potential. The nanoparticles were found to be stable and smaller than 500 nm in size, making it suitable for long-term use without causing potential formation damage for porous sandstones. The particles had a pore size of 2~6 nm and a specific surface area of 311 m²/g. The release behavior of the inhibitor was studied using UV-Vis spectroscopy, and it was found that the porous material provided sustained release of the inhibitor over extended times. A model is used to analyze the thermodynamics aspects of AI adsorption/desorption on silica and the effect of diffusion. These findings suggest that the synthesized material has potential as a candidate for applications in production wells in the oil and gas industry.