POLY 119 |
| High surface area, low density materials for the support of catalytically-active species can be produced using the clay aerogel process developed by the Schiraldi group. The decoration of the clays, used to produce these aerogels, with nanoparticles is accomplished through ethylene glycol reduction of metal acetate tetrahydrates in the presence of clay in a procedure similar to a literature method. The nanoparticles, as synthesized, range from 10-50 nm diameter for the smallest particles up to 100-1000 nanometers for agglomerated particle structures. The particles in the elemental state are deposited on the surface of montmorillonite clay in solution creating an active site at which a hydrogenation and isomerization reactions can occur. When the montmorillonite clay has been decorated with nanoparticle clusters the material it is converted into a hydrogel that is then either frozen in a dry ice-ethanol bath and freeze-dried to form an aerogel or is added drop wise to liquid nitrogen and freeze dried to form aerogel beads 3-5 millimeters in diameter. Once an aerogel is formed it is fired between 850-875 degrees Celsius for one hour to obtain a semi-ridge ceramic medium able to withstand submersion into a liquid. After firing, the ceramic aerogels are placed in a high pressure reaction vessel containing 1-octene and pure hydrogen gas. The reaction is heated to fifty degrees Celsius and the pressure is raised to and maintained at 4.5 atm for 12 hours. After 12 hours an aliquot of solution is taken for sampling and nuclear magnetic resonance spectroscopy is run to quantify the percent conversion of the reaction using a literature method. Comparisons of polymer-free and polymer-modified catalytic clay aerogel systems will be discussed. |
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Undergraduate Research in Polymer Science
6:00 PM-8:00 PM, Sunday, April 6, 2008 Morial Convention Center -- Hall A, Poster
Division of Polymer Chemistry |