Zeolites have directly impacted the production of fuels and chemicals from fossil fuel and renewable feedstocks. Our group has concentrated its focus on the synthesis of zeolites with tunable and/or controllable chemical and physical properties.  This presentation will focus on our efforts to synthesize zeolites to facilitate the conversion of complex biomass-based molecules to fuels and chemicals by 1) synthesizing zeolites containing acid and base sites and 2) synthesizing zeolites containing mesopores.  For zeolites containing acid and base sites, we synthesized and modified various aluminum containing ZSM-5 catalysts through the addition of a cerium source: 1) cerium-exchanged ZSM-5, 2) cerium/ZSM-5 via incipient wetness, and 3) cerium incorporated ZSM-5 using a dry gel synthesis method.1  These catalysts were then studied for the catalytic fast pyrolysis of carbohydrates. Interestingly, the Ce-exchanged and Ce/ZSM-5 incipient wetness catalysts behaved very similarly to their non-cerium containing analogues.  However, the Ce-incorporated catalyst produced lower amounts of BTX and more valuable oxygenated products (ketones, furans, aldehydes).  Overall, it was found that the method of cerium addition greatly affected the properties of the catalyst. Our efforts have since focused on understanding how the Ce-incorporated catalysts alter the selectivity.  Alternatively, we have used dry gel methods to synthesize ZSM-5 with mesopores by controlling the synthesis time and type of swelling agents.2 We have used these materials to determine optimal synthesis conditions to enhance the conversion of lignin model compounds to fuels and chemicals.  We have characterized these materials with a battery of techniques including X-ray diffraction (XRD), N2 physisorption, scanning electron microscopy (SEM), scanning transmission electron microscopy (STEM), transmission electron microscopy (TEM), NH3 temperature-programmed desorption, CO2 TPD, diffuse reflectance FT-IR, and diffuse reflectance UV-Visible spectroscopy.Neumann, G. T.; Hicks, J. C., ACS Catal. 2012 , 642-646.Neumann, G.T.; Hicks, J.C., Cryst. Growth Des., 2013 , 13, 1535�1542.

Synthetic strategies for tuning the selectivity in acid/base ZSM-5 catalysts

247th National Meeting (2014)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.