Particle characterization- size distribution, pore distribution- of precursor, micronized powder and cataslyst

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This proposal concerns catalyst manufacture, which accounts for $5 billion worth of sales in North America.  On a global basis, products derived from catalysis represent $3 trillion.  Despite the enormous impact of catalysis in our daily lives, there remains significant challenges in developing economic and environmental processes  The difficulty in working in this field relates to the interaction between the three primary phases of matter - solids, liquids and gases.  For example, we often begin with solution chemistry to form crystals (G-L).  The next step in the manufacturing process may include drying followed by micronization where the crystals are pulverized to a sub-micron size in air or liquid (G-S, L-S).  The third step involves granulation or spray drying in order to produce micro-spheres that have mechanical stability - attrition resistance, abrasion resistance, and crush strength - as well as the correct particle morphology - size distribution, shape, surface area, and porosity (L-S, G-L-S).  Finally, powders are employed in physical systems at elevated temperatures (1250 K) and pressures in the gas or liquid phase (G-S, L-S).   Our group is also working on reactor systems where we are seeking solid-solid reactions at elevated temperature (G-S-S). My group works in the general field of catalyst but in particular partial oxidation and dehydration: butane to maleic anhydride over a VPO catalyst, methanol to olefins over proprietary catalysts fabricated by Haldor-Topsoe, as well as Chemical Looping Combustion that requires a solid oxidant.  In each of these programs, particle size, surface area and pore size distribution are critical factors - at the synthesis stage, spray drying, and finally as a tool to examine the attrition rates in the reactors (to be able to distinguish between fractured particles and elutriation of fines).  These standard processes will be accompanied by equipment development in which we will attempt to modify the Particle Size Analyzer in order to be capable of monitoring the growth of crystallites on-line and in real time.  Most research in this area is performed ex-situ with a large variability with respect to the "optimum" residence time for crystal growth.