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  • Meet the CBR Faculty

 

 

Rolf Jentoft

 

Education and Professional

Current
Research Associate,
Affiliate Assistant Professor
School of Chemical, Biological and Materials Engineering

Education
PhD University of California at Davis, 1999 B.S. San José State University, 1991

Experience and Awards
Thermal Analysis Technology Leader, Johnson Matthey Catalysts, Billingham, UK (2006-2008) Scientist, Fritz Haber Institute, Max Planck Society, Berlin (1999-2006) Analyst II, OHM Corporation, Santa Rosa, CA (1988-1990) Chemist, Multi-Tech Environmental Testing Laboratory, Santa Rosa, CA (1984-1988)

CONTACT
Dr. Rolf Jentoft
Research Associate

Affiliate Assistant Professor

School of Chemical, Biological and Materials Engineering
University of Oklahoma
100 East Boyd, Sarkeys Engergy Center,
Norman, Oklahoma
73019-1004, USA

Email:rejentoft@ou.edu
Ph. office (405) 325 0465

Fax office (405) 325-5813

 

Rolf Jentoft

Research Interests

In order to utilize sustainable fuel sources such as biomass derived oils, these materials must undergo multiple processing steps. Catalysts can accelerate and direct the necessary reaction steps and can have a large impact on the viability of the refining process. My research is in the testing and characterization of catalysts and related materials used in the processing of hydrocarbons and oxygenates.

The most direct characterization of a catalyst is to measure its activity. Combining activity information with knowledge of the active surface can be used to direct improvement of the catalyst, and may lead to a fundamental understanding of how a catalyst works. However, because a catalyst at room temperature and exposed to air does not have the same structure as the same material under reaction conditions (usually increased temperature and reactant atmosphere), it is useful to characterize the catalyst under reaction conditions. X-ray absorption spectroscopy is an element specific spectroscopic technique that gives information on the local environment (within about 5 Ǻ) as well as information on the average valence. We have designed and constructed measurement cells for transmission and fluorescence mode measurements of catalyst under reaction conditions.

The synthesis of catalysts usually requires several thermal treatments such as drying, calcination, and activation. Optimization of these steps can enhance the activity of the catalyst. To efficiently optimize thermal treatment it is useful to understand the kinetics of the transformations occurring during treatment. Kinetic information can be obtained through measurement of changes in weight (Thermo Gravimetric Analysis), gas products analysis, and measurement of heat effects occurring during heating in a controlled atmosphere. Temperature programmed desorption, reduction, or oxidation can also be used to characterize acid/base properties, oxidation state, reactivity, and to optimize regeneration parameters for catalysts.

Patent

EP1834939 (A1) “Hydrogenation process using catalyst comprising ordered intermetallic compound” R. Giedigkeit, M. Armbrüster, K. Kovnir, J. Grin, R. Schlögl, J. Osswald, T. Ressler, R. E. Jentoft

Selected publications

Jentoft R.E., Hahn, A.H.P., Jentoft F.C., Ressler T. In-situ XANES study of Mn in promoted sulfated zirconia catalysts, Physical Chemistry Chemical Physics. 7(14): 2830-2838 (2005)

Jentoft R.E., Hahn A.H.P., Jentoft F.C., Ressler T. XAS in situ cell for measurements of Mn and Fe promoted sulfated zirconia catalysts Physica Scripta T115: 794-797 (2005)

Jentoft R.E., Deutsch S.E., Gates B.C. Low-cost, heated, and/or cooled flow-through cell for transmission x-ray absorption spectroscopy Review of Scientific Instruments 67(6): 2111-2112 (1996)

Jentoft F.C., Hahn A.H.P., Kröhnert J., Lorenz G., Jentoft R.E., Ressler T., Wild U., Schlögl R., Hässner C., Köhler K. Incorporation of manganese and iron into the zirconia lattice in promoted sulfated zirconia catalysts Journal of Catalysis 224(1): 124-137 (2004)

Jentoft R.E., Tsapatsis M., Davis M.E., Gates B.C. Platinum clusters supported in zeolite LTL: Influence of catalyst morphology on performance in n-hexane reforming Journal of Catalysis 179(2): 565-580 (1998)

Müller J.-O., Su D.S., Jentoft R.E., Wild U., Schlögl R. Diesel engine exhaust emission: Oxidative behavior and microstructure of black smoke soot particulate Environmental Science and Technology 40: 1231-1236 (2006)

Müller J.-O., Su D.S., Jentoft R.E., Kröhnert J., Jentoft F.C., Schlögl R. Morphology controlled reactivity of carbonaceous materials towards oxidation Catalysis Today 102: 259-265 (2005)

Purnama H., Ressler T., Jentoft R.E., Soerijanto H., Schlögl R., Schomäcker R. CO formation/selectivity for steam reforming of methanol with a commercial CuO/ZnO/Al2O3 catalyst Applied Catalysis A - General 259(1): 83-94 (2004)

Günter M.M., Ressler T., Jentoft R.E., Bems, B. Redox behavior of copper oxide/zinc oxide catalysts in the steam reforming of methanol studied by in situ X-ray diffraction and absorption spectroscopy Journal of Catalysis 203(1): 133-149 (2001)