High performance carbon dioxide foams of nanocomposites of binary colloids for effective carbon utilization in enhanced oil recovery applications

Most of conventional carbon dioxide (CO2) foams show limitations in practical applications due to several issues such as thermal stability, disintegration of bubble, dissolution of lamella, and deterioration of rheological property. However, stability of these foams can be improved by including a nanomaterial that makes them stable via Pickering stabilization. Homo-agglomeration, causing large size aggregates, is an important issue with colloidal formulations which reduces foam efficacy due to unsuccessful nanopartide (NP) adsorption on CO2 surface. Therefore, this study reports the use of nanocomposite of binary NPs (SiO2 and TiO2) in stabilizing CO2 foams at moderate pressure (70 bar) and temperature (90 degrees C) conditions, to find their use in oilfield practices. CO2 foam stabilized by nanocomposites was studied for thermal stability using microscopic and rheological analysis at 70 bar/90 degrees C followed by UV-vis and contact angle tests to investigate colloidal interaction with CO2. TiO2 inclusion resulted into remarkable changes in the thermal stability and rheological behavior of SF foam by delaying the process of CO2 coalescence. In addition, the study suggests that TiO2 NP reduces the size of foam bubble through enhanced adsorption as demonstrated by lamella formation and that foam (STF-3, 0.5 wt% SiO2 + 0.1 wt% TiO2) showed least dependency on varying shear, pressure, and temperature conditions. Moreover, the rheological properties such as viscosity and viscoelastic nature of CO2 foams, stabilized by these nanocomposites, show potential for real field applications. Thus, the proposed study highlights the important mechanism of CO2 foam of binary NP system (nanocomposites) followed by rheological analysis of CO2 foam at real conditions, which is useful for CO2 based oil recovery applications. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

The study focuses on stabilizing CO2 foams using binary nanocomposites at moderate pressure and temperature, resulting in improved thermal stability and rheological behavior. The inclusion of TiO2 NP enhances adsorption and reduces bubble size, leading to a foam with minimal dependency on varying shear, pressure, and temperature conditions. The research highlights the potential of these nanocomposites for real field applications in CO2 based oil recovery.