Wettability alteration properties of fluorinated silica nanoparticles in liquid-loaded pores: An atomistic simulation

Sepehrinia, K ; Sharif University of Technology | 2016

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  1. Type of Document: Article
  2. DOI: 10.1016/j.apsusc.2016.02.218
  3. Publisher: Elsevier , 2016
  4. Abstract:
  5. Control over the wettability of reservoir rocks is of crucial importance for enhancing oil and gas recovery. In order to develop chemicals for controlling the wettability of reservoir rocks, we present a study of functionalized silica nanoparticles as candidates for wettability alteration and improved gas recovery applications. In this paper, properties of fluorinated silica nanoparticles were investigated in water or decane-loaded pores of mineral silica using molecular dynamics simulation. Trifluoromethyl groups as water and oil repellents were placed on the nanoparticles. Simulating a pore in the presence of trapped water or decane molecules leads to liquid bridging for both of the liquids. Adsorption of nanoparticles on the pore wall reduces the density of liquid molecules adjacent to the wall. The density of liquid molecules around the nanoparticles decreases significantly with increasing the number of trifluoromethyl groups on the nanoparticles' surfaces. An increased hydrophobicity of the pore wall was observed in the presence of adsorbed fluorinated silica nanoparticles. Also, it is observed that increasing the number of the trifluoromethyl groups results in weakening of liquid bridges. Moreover, the free energy of adsorption on mineral surface was evaluated to be more favorable than that of aggregation of nanoparticles, which suggests nanoparticles adsorb preferably on mineral surface
  6. Keywords:
  7. Flourinated silica ; Molecular dynamics ; Nanoparticle ; Surface chemistry ; Wettability
  8. Source: Applied Surface Science ; Volume 371 , 2016 , Pages 349-359 ; 01694332 (ISSN)
  9. URL: http://www.sciencedirect.com/science/article/pii/S0169433216304056