Banca de DEFESA: VALDIVINO FRANCISCO DOS SANTOS BORGES

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : VALDIVINO FRANCISCO DOS SANTOS BORGES
DATE: 22/12/2023
TIME: 14:00
LOCAL: videoconferência
TITLE:

Adsorption of surfactants in reservoir rocks via micellar solution: evaluation of experimental design and implementation of parameters

KEY WORDS:

Surfactante; Sandstone; Limestone; Adsorption; Equilibrium Isotherms

PAGES: 140
BIG AREA: Ciências Exatas e da Terra
AREA: Química
SUBÁREA: Físico-Química
SPECIALTY: Química de Interfaces
SUMMARY:

The adsorption of surfactants on rock surfaces can alter their hydrophobicity, surface charge, and other important properties that govern enhanced oil recovery (EOR) processes, such as reducing the interfacial tension between water and oil and increasing permeability. In general, the need to control and/or reduce the adsorption of surfactants on reservoir rock surfaces has been a challenging task in enhanced oil recovery (EOR) methods, as it directly impacts the project's economy. This requires a comprehensive study and understanding of the adsorption mechanism on rocks. The primary functions of this method are to reduce the water/oil interfacial tension and alter the wettability of the reservoir rock, which is often oil-wet, making it water-wet. This property of surfactants is due to their amphiphilic nature. In this study, the adsorption behavior via micellar solutions of ionic surfactants (OCS, OCBS, OMS, and SDS) and non-ionic surfactants (NP 9.5EO, NP 11EO, and NP 15EO) on carbonate and sandstone rocks was investigated. The finite bath method was employed to assess adsorption in all systems. For the anionic surfactants, a factorial experimental design was applied to optimize the adsorption process. It was observed that the adsorption of OCS, OCBS, and OMS was effective in limestone and negligible in sandstone, while SDS showed low adsorption efficiency in both rocks. The adsorption efficiency in limestone was 85.74%, 82.52%, and 45.30% for OCS, OCBS, and OMS, respectively. The isotherm data were well described by the Sips isotherm model for the surfactants OCS, OCBS, and OMS. The results indicated that the adsorption fitted well with the pseudo-second-order kinetic model. The Langmuir model simulated the adsorption isotherms of OCS better than the Freundlich model at three different temperatures of 298, 313, and 333 K. Thermodynamic parameters (ΔH, ΔS, and ΔG) indicated that the OCS adsorption process was spontaneous and endothermic. The experiments involving non-ionic surfactants were conducted according to the Scheffé network and showed an adsorption efficiency of 66.89% for NP-15EO, 67.15% for NP-11EO, and 70.60% for NP-9.5EO. Point F was chosen as the ideal point since it remained constant during the experiments, besides being a water-rich region and having low butanol content. The sandstone exhibited oil-favorable wettability, which underwent wettability inversion after treatment. Among the studied models, the Redlich-Peterson isotherm model was the best fit, indicating that the adsorption process occurs in monolayers and multilayers. The adsorbents were characterized by Fourier Transform Infrared Spectroscopy (FTIR), Thermal Analysis (TG/DTG), X-Ray Diffraction (XRD), X-ray Fluorescence (XRF), Scanning Electron Microscopy (SEM), Particle Size Analysis, and Zeta Potential Analysis.

COMMITTEE MEMBERS:
Externo ao Programa - 1753094 - ALCIDES DE OLIVEIRA WANDERLEY NETO - nullInterno - 1198847 - JOSE LUIS CARDOZO FONSECA
Externa à Instituição - MICHELLE SINARA GREGÓRIO DANTAS - IFRN
Externa à Instituição - MONICA RODRIGUES DE OLIVEIRA - UFERSA
Presidente - 2087667 - TIAGO PINHEIRO BRAGA
Externa ao Programa - 1531209 - VANESSA CRISTINA SANTANNA - null