Chemical Engineering

Professor Liberatore: Rheology research

Rheology research projects cover topics from renewable energy to polishing. The work of our research team has led to the Rudolf Hering Medal from the American Society of Civil Engineers for the best paper in environmental engineering as well as more than 10 paper and poster awards earned by undergraduate and graduate students. Publications are available at this link.

Wood chips after being compressed

Biomass materials

High solids biomass slurries of corn stover, granular wood chips materials, and algae suspensions all exhibit interesting rheology. Understanding the flow of concentrated slurries and granular materials is critical to scaling up the production of biofuels and biobased chemicals. 

Fuel cell anion exchange membrane.

Anion exchange membranes And Polymer materials

Linking the mechanical properties  under controlled temperature and humidity conditions with conductivity and processing should produce an optimized membrane for a fuel cell. Other polymer composites and nanomaterials are also studied.

Fumed silica slurry in a test tube (looks like milk).

Shear thickening slurries

Fumed silica suspensions are important in toothpaste, cosmetics, and chemical mechanical polishing. Shear thickening is an increase in viscosity with increasing shear or flow that can be either beneficial (stopping bullets) or detrimental (scratch wafers for computer chips).

black oily liquid with hydrates inside pressure rheometer cell

Clathrate hydrates

High pressure rheology allows the study of methane hydrates as these ice-like structures form, grow, aggregate, rearrange, and dissociate.

Alaska heavy oil between plates on a rheometer

Alaska heavy oil

Relating chemistry with ambient and high pressure rheology could lead to improved heavy oil recovery and production, such as for North Slope Alaska Ugnu heavy crude oils.

Crystals in test tube of fatty acid methyl esters (chemicals found in biodiesel fuel)

Waxy oils and shear-induced phase changes

Examining wax appearance temperature as a function of shear could help improve flow assurance operations, and flow alters phase changes in materials such as fatty acid methyl esters found in biodiesel.

creams and lipsticks arranged in a circle


From emulsions to lipsticks, flow and rheology, formulation, and function of complex fluids and materials related to cosmetics and personal care products are being studied.

Alaska heavy oil between plates on a rheometer

Surfactants and adhesives

Wormlike micelles form interesting viscoelastic fluids, and polyelectrolyte complexes form gel-like adhesives that can work under water.

Green polymer filaments in a channel of water

Polyelectrolytes and drag reducing polymers

From xanthan gum and polyacrylamides, entangled polyelectrolyte rheology can be altered using concentration and salt.

Last Updated: 6/27/22