Green Chemistry and Engineering
Green Chemistry Projects
Objective:
To develop and demonstrate cleaner synthesis for commodity and specialty chemicals through improved catalysis, use of solvent-free or alternative reaction media and raw materials.
Background:
The ability to transform an inert alkane molecule into a valuable chemical commodity has been the subject of intense chemical research for a number of decades. These oxidized products: alcohols, ketones, aldehydes and carboxylic acids are currently derived from processes which use stringent conditions or materials including strong acid mediums, toxic metal catalysts, abrasive oxidants and high temperatures and/or pressures. Additional disadvantages include decreased selectivities to the light oxygenates and by-product formation. As environmental concerns and regulations become more rigorous, the need for a catalytic oxidation process that utilizes mild or ambient conditions (temperature, pressure, oxidant, catalyst and solvent) is heightened
Investigations within our laboratories have focused towards the photochemical activity of semi-conductors as a low-temperature alternative for the oxygenation of alkanes. Titanium dioxide, a low cost and non-toxic material, has been widely utilized in the liquid phase for the mineralization of pollutant hydrocarbons under ambient conditions. The objective of the present NRMRL research is to demonstrate and evaluate the feasibility of light activated titania (TiO2) and molecular oxygen for the activation and subsequent selective oxidation of hydrocarbons.
The objective of this in-house research effort is to design, construct and utilize a heterogeneous gas- and liquid-phase photoreactor for the selective partial oxidation of alkanes and olefins into their corresponding oxygenates. Research currently being conducted includes: investigating the use of multiple reactor configurations, the application of nano-crystalline films of TiO2 on a permeable support and the potential use of additional catalysts, as well as co-catalysts, to increase the conversion, yield, and selectivity of the synthesized oxygenates
Primary Investigators:
Dr. E. Sahle-Demessie
(513) 569-7739
sahle-demessie.endalkachew@epa.gov
Dr. Michael Gonzalez
(513) 569-7998
gonzalez.michael@epa.gov
Dr. Rajender Varma
(513) 487-2701
varma.rajender@epa.gov
26 West Martin Luther King Drive
Mail Stop 443
Cincinnati, Ohio 45268
Fax:(513) 569-7677