Ethanol conversion to 1,3-Butadiene

Since its discovery in the late 19th century, synthetic rubber has become a popular replacement for natural rubber. Currently, the world produces and consumes more synthetic rubber than natural rubber. In the first half of 2015, the United States alone produced and consumed 1.5 million tons of synthetic rubber, more than 20% of all synthetic rubber produced in the world at the time. To manufacture synthetic rubber, 1,3butadiene must be produced and polymerized. Presently, steam cracking of petroleum naphtha remains the most popular and costefficient manufacturing process. Alternatives are actively being researched due to the unsustainability of the oil industry. This research focuses on the conversion of ethanol to butadiene. ZrOSiO2 catalysts, produced by wetness impregnation, are studied with TPSR, DRIFTS, and DFT to determine optimal reaction conditions and mechanisms. TPSR data shows that with a 10% ZrO impregnated SiO 2 catalyst and under the presence of acetaldehyde, the conversion occurs at a much lower temperature and yields the most butadiene. DRIFTS data shows that the reaction occurs in neither only the gas phase nor the catalyst surface, and that the reaction only proceeds when the reactants exist at both locations. Finally, DFT data shows that singular and dimer ZrO sites exists on the catalyst surface in 4 and 5 fold coordination to facilitate the reaction. Future research will use DRIFTS to study the steady state conversion of ethanol at temperatures and conditions previously determined by TPSR. DFT will be used to simulate the reaction mechanisms to compare with DRIFTS data and to calculate the reaction's energy barriers.