Al-Asadi, AkramRodil Rodríguez, EvaSoto Campos, Ana María2025-12-022025-12-022022-11Al-Asadi, A., Rodil, E., & Soto, A. (2022). Nanoparticles in chemical EOR: A review on flooding tests. Nanomaterials, 12(23), 4142. https://doi.org/10.3390/nano12234142https://hdl.handle.net/10347/44164The use of nanofluids is showing promise as an enhanced oil recovery (EOR) method. Several reviews have been published focusing on the main mechanisms involved in the process. This new study, unlike previous works, aims to collect information about the most promising nano-EOR methods according to their performance in core-flooding tests. As its main contribution, it presents useful information for researchers interested in experimental application of nano-EOR methods. Additional recoveries (after brine flooding) up to 15% of the original oil in place, or higher when combined with smart water or magnetic fields, have been found with formulations consisting of simple nanoparticles in water or brine. The functionalization of nanoparticles and their combination with surfactants and/or polymers take advantage of the synergy of different EOR methods and can lead to higher additional recoveries. The cost, difficulty of preparation, and stability of the formulations have to be considered in practical applications. Additional oil recoveries shown in the reviewed papers encourage the application of the method at larger scales, but experimental limitations could be offering misleading results. More rigorous and systematic works are required to draw reliable conclusions regarding the best type and size of nanoparticles according to the application (type of rock, permeability, formation brine, reservoir conditions, other chemicals in the formulation, etc.)eng© 2022 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license.Attribution 4.0 Internationalhttp://creativecommons.org/licenses/by/4.0/ReviewEORNano-fluidCore-floodingjournal article10.3390/nano12234142open access