University of Toledo : Chemical and Environmental Engineering

Ph.D. in Chemical Engineering, Rutgers University, New Brunswick, NJ
M.S. in Chemical Engineering, Rutgers University, New Brunswick, NJ
B.S. in Chemical Engineering, Cornell University, Ithaca, NY

Current research is focused in the area of separations, particularly crystallization and precipitation processes and biofuels production.

In the area of bioseparations, we are focusing on protein crystallization with application to single crystal growth for structure determination and industrial crystallization for protein purification. Projects include impurity partitioning and defect formation, fundamental studies of nucleation kinetics, and optimization of cryogenic cooling of protein crystals.

In the biofuels area, we are developing a pretreatment method for lignocellulose using the unique solvation properties of ionic liquids. This is a collaborative project with Sasidhar Varanasi (Chemical Engineering Dept., UT) and Jared Anderson (Chemistry Dept, UT). Cellulose, a polymer of glucose, is the most abundant renewable resource in the world. However, its potential as a source of raw materials is limited by the strong hydrogen bonding network in its highly crystalline natural form. Disruption of this structure allows effective chemical modification or hydrolysis of cellulose into its glucose subunits. Ionic liquids (ILs) are non-derivitizing solvents of cellulose that efficiently disrupt its structure without production of fermentation inhibitors. In our process, cellulose is pretreated with an IL forming an easily modified amorphous structure. The amorphous cellulose substrate treated with IL can be enzymatically hydrolyzed into its glucose subunits at rates almost two orders of magnitude greater than untreated cellulose.

Dadi, A., C.A. Schall, S.Varanasi, (2007) Mitigation of cellulose recalcitrance to enzymatic hydrolysis by ionic liquid pretreatment, Applied Biochemistry and Biotechnology, 136-140, 407-421.

Dadi, A. P., S. Varanasi, C. A. Schall (2006) Enhancement of cellulose saccharification Kinetics using an ionic liquid pretreatment step, Biotechnology and Bioengineering, 95(5), 904-910.

Izaac, A., C.A. Schall and T. C. Mueser (2006) Assessment of a preliminary solubility screen to improve crystallization trials: uncoupling crystal condition searches, Acta Crystallographica Section D: Biological Crystallography D62, 833-842.

Chinte, U.; B, Shah,Yu Sheng Chen, Yu Sheng; A. A. Pinkerton, C. A. Schall, B. L. Hanson, Cryogenic (<20 K) helium cooling mitigates radiation damage to protein crystals. Acta Crystallographica, Section D: Biological Crystallography (2007), D63(4), 486-492.

Shah, B., C.A. Schall, (2006) Measurement and modeling of the glass transition temperatures of multi-component solutions, Thermochimica Acta, 443, 78-86.

Bhamidi, V.; S. Varanasi; C.A. Schall, (2005). Protein crystal nucleation: Is the pair interaction potential the primary determinant of kinetics? Langmuir, 21(20), 9044-9050.

Chinte, U., B. Shah, K. DeWitt, K.K. Kirschbaum, A.A. Pinkerton, C.Schall, (2005), Sample size: an important parameter in flash-cooling macromolecular crystallization solutions, J. Applied Crystallography, 38(3), 412-419.

Bhamidi, V.; S. Varanasi; C.A . Schall, (2002) Measurement and modeling of protein crystal nucleation kinetics, Crystal Growth & Design, 2(5), 395-400

Young, P.; C.A. Schall, (2001) Cycloalkane solubility determination through differential scanning calorimetry, Thermochimica Acta 367-368, 387-392.

Bhamidi, V.; E. Skrzypczak-Jankun, C.A. Schall, (2001) Dependence of nucleation kinetics and crystal morphology of a model protein system on ionic strength, J. of Crystal Growth, 232, 77-85.

Cordoba, A.J.; C.A. Schall, (2001) Application of a heat transfer method to determine wax deposition in a hydrocarbon mixture, Fuel 80, 1285-1291.

Cordoba, A.J.; C.A. Schall, (2001) Solvent migration in a paraffin deposit, Fuel 80, 1279-1284.

Schall, C.A., J.M. Wiencek. Chapter 8: Product Recovery and Purification via Precipitation and Crystallization, Handbook of Downstream Processing, (1997) E. Goldberg, ed., Chapman & Hall.