Methanol Clustering Work Accepted!

Our latest work has been accepted in the Journal of Physical – Chemistry B. In it, we characterize and model the clustering of methanol in supercritical CO2! It will help improve nuclear fuel reprocessing strategies!

Abstract

Co-solvent clustering in complex fluids is fundamental to solution phase processes, influencing speciation, reactivity, and transport. Herein, methanol (MeOH) clustering in supercritical carbon dioxide is explored with pulsed field gradient, diffusion-ordered nuclear magnetic resonance spectroscopy (DOSY-NMR) and molecular dynamics (MD) simulations. Refinements on the application of self-association models to DOSY-NMR experiments on clustering species are presented. Network analysis of MD simulations reveals an elevated stability of cyclic tetrameric clusters across MeOH concentrations that is consistent with experimental DOSY-NMR molecular cluster distributions calculated with self-association models that include both cooperative cluster assembly and entropic penalties for the formation of large clusters. Simulations also detail the emergence of cluster-assembly and -disassembly reactions that deviate from stepwise, monomer addition or removal. This unique combination of experiment, simulation, and novel analyses facilitates refinement of models that describe co-solvent aggregation with far-reaching impact on the prediction of solution phase properties of complex fluids.

Link

https://doi.org/10.1021/acs.jpcb.9b02305

Funding

Collaborators

Aurora Clark – WSU Chemistry
Sue Clark – WSU Chemistry, PNNL