Oxidative desulfurization (ODS) with hydrogen peroxide (H2O2) is a green and promising method for the chemical abatement of sulfur-containing molecules in heavy fuels that necessarily need to be removed prior to combustion. Group IV (e.g., Ti, Zr, and Hf) and V (e.g., Nb and Ta) metal atoms incorporated into the zeolite *BEA framework activate H2O2 to form pools of superoxide and hydroperoxide intermediates (collectively referred to as M-(O2)) that are active for thiophene oxidation. Kinetic measurements of 2,5-dimethylthiophene (2,5DMT) oxidation as a function of reactant concentrations show that all catalysts reversibly adsorb H2O2 followed by irreversible activation to form pools of M-(O2) which then react with 2,5DMT or H2O2 to form the corresponding oxidation or decomposition product, respectively. Ongoing studies are examining how the activation barriers for thiophene oxidation and hydrogen peroxide decomposition vary with the structure and environment of the catalysts and the resultant design parameters that affect the rates and selectivities for ODS.
University of Illinois at Urbana-Champaign
Dr. David Flaherty
Department of Research Advisor:
Chemical & Biomolecular Engineering
Year of Publication: