Analysis of Acid Catalyzed Reaction using Isotopic Transient Kinetics

University Of Pittsburgh, Pittsburgh PA

Investigators

Abstract

Abstract Proposal Title: Analysis of Acid Catalyzed Reactions Using Isotopic Transient Kinetics Proposal Number: CTS-9988412 Principal Investigator: James Goodwin Institution: University of Pittsburgh The objective of this project is to use isotopic transient kinetic analysis (ITKA) to obtain in situ information on kinetic parameters for solid acid catalysts. The work will focus on determining the nature of the high activity and selectivity of sulfated zirconia (SZ) catalysts for butane isomerization, a model reaction. Parameters studied will include average residence time and concentration of active surface intermediates leading to iso-butane during n-butane isomerization on SZ and persulfated zirconia catalysts. Analytical techniques such as XPS, FTIR, NMR, and microcalorimetry will complement ITKA studies. An overall goal of this work is to understand the nature of active sites such that the sites on future catalysts might be more precisely tailored. Several specific questions need to be answered about SZ catalysts before more rational design can proceed. It is unclear why persulfated zirconia, containing a lower concentration of sulfate, gives higher activity for n-butane isomerization. It is also unclear why alumina-promoted catalysts promote coke formation but also have better catalyst stability. A successful solid-acid catalyst would replace liquid-acid catalysts, which lead to corrosion, catalyst separation, and environmental problems from acid recycle and disposal.