Impact of Organic-Inorganic Interactions on Pore Networks and Fluid Transport
EMSL Project ID
60206
Abstract
The proposed work takes advantage of unique EMSL capabilities to study how organic molecules chemically tethered to pore surfaces impact the pore sizes, pore connectivity, and dynamics of sorbed fluids in common rock and soil minerals. Importantly, the proposed work builds upon techniques developed during our prior Large Scale Research proposal (50761)1-2 to probe the exchange of (bio)geochemically important fluids, such as methane and water, between nm-scale pores and other pore types. Such meso-scale fluid dynamics occur at the transition between nano-confined and bulk-like fluids and remain challenging to probe in the laboratory. The current proposal also uses the new HeliScan XCT instrument and its sub-micron resolution to characterize the micron and larger pore network in our samples. Our findings will be integrated with molecular dynamics models conducted by collaborators to provide unique insight into how fluid structure and mobility change as pore surfaces become organo-modified and as the pore H2O content varies. Hypotheses that will be tested include: 1. Increasing the H2O activity of methane increases the rate and fraction of nm-confined methane exchanging between nm-scale pores and larger pore types in both functionalized and unfunctionalized inorganic pores.
2. Tethering of small organic molecules to silica pore surfaces decreases the mean dynamic pore size accessible by methane under wet and dry conditions.
3. Tethering of small organic molecules to silica pore surfaces increases the hydrocarbon exchange rate between nm-scale pores and larger pore types in dry and wet methane.
4. These principles and methods can be applied to understand hydrocarbon adsorption and dynamics in natural porous systems relevant to surface soils and shales.
Project Details
Project type
Exploratory Research
Start Date
2021-12-01
End Date
2022-09-30
Status
Closed
Released Data Link
Team
Principal Investigator
Co-Investigator(s)