After a four-year submission and review process, Dr. Tracy Benson, a professor of chemical engineering at
Dr. Tracy Benson
Lamar University, and Russell Chianelli, a chemistry professor at the University of Texas-El Paso, have been awarded a patent for a catalyst material to make medium chain alcohols using Fischer – Tropsch reactions.
The catalyst, a combination of potassium and cesium on molybdenum oxide clays, is capable of producing C6 – C8 (hexanol, heptanol, and octanol) from carbon monoxide and hydrogen. According to Benson, the catalyst, referred to as “alkali-promoted MoS2,” produces these alcohols at much lower pressures, which results in production of detergents, fragrances and surfactants affording the fine chemical industry and ultimately the consumer, a cost savings.
The gases required for synthesis are readily available from natural gas waste streams, waste carbon dioxide, or biomass gasification processes. “While Fischer – Tropsch processes have been around for nearly a century, it is often considered uneconomical due to unwanted side reactions and products,” said Benson. “The properties of this unique catalyst material make it very selective in the product formation, adding to its economic benefits.”
The collaborative research effort began in early 2013, when Benson and Chianelli met and realized they had a mutual interest in the subject and the concept of this novel catalyst was forged. Graduate students and post-doctoral fellows aided in the laboratory work, and their intellectual contributions are reflected in their designation as co-inventors on the patent.
“The UTEP and LU teams worked back and forth with each other to develop the “Goldilocks factors” - just the right percentages and combinations of particular metals to target the very specific alcohols - for both the catalysts and the reaction conditions,” said Benson. “Through synthesis and testing of the powdered catalyst material, the right combinations were determined for optimum yield and selectivity of the medium chain alcohols. Additional reaction tests identified the best temperatures, pressures, and ratios (H2/CO) for maximum conversion of the synthesis gas.”
A provisional patent was initially submitted in the summer of 2015.