Start
Jan 20, 2011 - 16:00
End
Jan 20, 2011 - 17:30
Venue
Creativity Hall (Room No 118)
Event Type
Speaker
Dr. Rahul Nabar Deptt of Chemical and Biological Engineering University of Wisconsin-Madison.
Title
Application of quantum mechanical calculations to selected problems in catalytic petroleum processing.
Abstract: High performance computing (HPC) strategies can today be applied to petroleum-processing problems including those in the domain of heterogeneous catalysis. Advances in ab-initio quantum chemistry codes (i.e. Density Functional Theory) and the ability to parallelize calculations over hundreds of CPUs allow us to evaluate kinetics and thermochemistry for reaction networks of practical interest. The Minimum Energy Pathway can be elucidated and further calculations of vibrational-frequencies pre-exponential-factors and entropies can be combined into a detailed microkinetic model. Fundamental chemical-insights into electronic structure molecular geometry and the identity of transition-states are also obtainable. The talk illustrates this computational approach using two industrially important problems: Fischer Tropsch Synthesis and bimetallic catalyst design. Fischer-Tropsch Synthesis (FTS) is a promising gas-to-liquid (GTL) technology for the production of clean diesel from syngas. In spite of decades of extensive research there is no consensus about mechanistic details and rate-determining-steps on FTS catalysts (Iron and Cobalt). We clarify the confounding issues using a strategic combination of experiments and modelling. Finally we demonstrate how quantum-chemical methods can be used to perform systematic screening of bimetallic alloy-catalysts for the rational design of novel poison-resistant catalysts. In both the problems discussed the synergy between experimental techniques and computational approaches is the dominant theme.