Multiscale Investigations of Species Capture from Dilute Solution

Tulane University, New Orleans LA

Investigators

Abstract

In the conversion of biomass to renewable biofuels, an important intermediate step is the recovery of dilute organic molecules that will serve as the fuel from an oil-water mixture. This separation must be done with utmost energy efficiency, to maximize the net energy recovered from the process. Similarly, very little of the organics must be left in the water, to maximize the amount of biofuels produced. Purification of the water would enable the energy sector to reuse the water. This proposal will use low-energy adsorption on functional surfaces to efficiently remove organics from oil-water mixtures by developing fundamental insights into how the chemical composition of functional surfaces impacts recovery. This project will couple molecular simulations and experimental studies to probe the molecular mechanisms for adsorption of acetic acid and guaiacol from water, two organics which serve as models for the complex mixture in conversion of biomass to biofuels. These model compounds were chosen to specifically probe short versus long range molecular interactions. In addition to standard adsorption and chromatographic methods, NMR spectroscopy will monitor the dynamics of binding and diffusion. Molecular simulations will be validated by the experimental measurements, and then used to examine the roles of electrostatic and hydrophobic interactions on selective adsorption. The outcome will be to develop predictive design rules to create novel hybrid functionalized materials. Outreach efforts will support and expand the pipeline of K-12 and undergraduate students to pursue careers in the STEM workforce. Strategies to recover dilute biologically derived organics from water will impact the energy, agriculture, and environmental sectors, with students trained to lead scientific solutions to energy-water challenges.