Journal of Petroleum & Environmental Biotechnology

Mechanistic study of nanoparticle retention in porous media using the DLVO theory

4^th International Conference on Petroleum Engineering

August 15-17, 2016 London, UK

E R Abdelfatah, K Kang, M Pournik, B Shiau and J Harwell

University of Oklahoma, Norman, USA

Posters & Accepted Abstracts: J Pet Environ Biotechnol

Abstract:

Nanoparticles are small enough to transport through the porous media. However, they can be retained on the pore walls by electrostatic interaction with the rock surface minerals. DLVO theory is used to understand the nanoparticle interaction with the pore walls at different ionic strength, temperature, and pH. For the case where the total interaction is repulsive, where an energy barrier exists between the nanoparticles and the pore walls, the rate of deposition has been derived. The maximum capacity of the rock surface is assumed to be monolayer coverage and follows the Langmuir isotherm. Rates of deposition of different nanoparticles onto different rocks are different due to their surface chemical properties. The rate of deposition and maximum deposition capacity onto sandstone were observed to be less than that of limestone. When energy barrier is present, rate of deposition decreases as temperature increases and when energy barrier vanishes, rate of deposition increases as temperature increases. High ionic strength increases rate of deposition. At certain condition, a critical ionic strength, which may be no less than 0.1 M (~ 0.3 wt% NaCl), exists. Above this critical ionic strength, the rate of deposition has a high value and increases gradually. At low and high pH, rate of deposition is limited due to the presence of energy barrier. However, the rate of deposition becomes high as the pH is in between the isoelectric points of nanoparticles and rock. The time-dependent rate of deposition decreases as more nanoparticles cover the pore walls.

Biography :

Email: Elsayed.Raafat@ou.edu