Professor Friederike Jentoft of the Chemical Engineering Department has received a $330,000 grant from the National Science Foundation (NSF) to study new catalysis methods that make chemical processes more environmentally friendly by reducing chemical waste.
Jentoft’s NSF project is titled “Steering Selectivity in Aldol Reactions by Control of Relative Effective Reaction Rates in Porous Catalysts.”
Jentoft’s UMass research laboratory focuses on catalysis. As she explains, “Catalysts facilitate chemical reactions and enable the efficient industrial production of chemicals and fuels. Our goal is to understand how catalytic reactions proceed and how performance of a catalyst is linked to its composition and structure.”
Jentoft adds that “With this knowledge, we seek to design novel, more effective catalysts. Key competences of our laboratory are in the areas of catalyst preparation, structural and surface characterization, kinetics analysis, and spectroscopic monitoring of the adsorption and reaction of molecules on surfaces.”
Jentoft’s collaboration on the NSF grant with Assistant Professor Oz M. Gazit of the Wolfson Department of Chemical Engineering at the Technion-Israel Institute of Technology resulted from a series of synchronous events. In 2017 Jentoft traveled to the 8th Eastern Mediterranean Chemical Engineering Conference in Haifa, Israel, as supported by an NSF travel grant obtained by Steven Cramer of Rensselaer Polytechnic Institute. Jentoft was part of the U.S. delegation as a representative for the field of catalysis, and during the visit she learned about Gazit and his interest in aldol condensation.
Aldol condensation is an essential reaction in many syntheses of bulk, fine, and specialty chemicals, says Jentoft, and shows promise for upgrading biomass-derived feedstocks to fuels or chemicals.
As Jentoft says, the objective of the current NSF research “is to steer this chemical reaction to give the desired product without generating a multitude of side products. The approach is to develop new solid catalysts and, by varying their surface chemical composition and pore morphology, tune their chemical and physical properties for optimal performance.”
Jentoft says that the new knowledge and fundamental understanding emerging from this collaborative work between UMass Amherst and the Technion-Israel Institute of Technology will serve to direct aldol condensations and other similarly complex and pivotal chemical reactions. In addition, the project will contribute to U.S. competitiveness in chemical manufacturing of bio-renewable products and will promote training of a diverse workforce skilled in biomass processing.
As Jentoft writes, “Aldol reactions consist of two sequential steps, addition and subsequent dehydration. Cross aldol condensations, particularly those involving unsymmetrical ketones, can lead to a multitude of primary and secondary products. The central hypothesis of this project is that selectivity in aldol reactions, which is governed by relative effective reaction rates, can be tuned by tailoring the active surface sites and effectiveness factors.”
While theory on the influence of transport limitations on the selectivity in parallel and sequential reactions has been outlined long ago, according to Jentoft, there are few realizations of these concepts in complex liquid phase reactions.
“This research project rigorously tests the practical viability of these concepts by manipulating surface chemistry and pore structure of the catalysts,” says Jentoft.
Jentoft also explains that “The main catalyst platform is layered double hydroxides, because they allow for a wide and independent variation of chemical and physical properties; that is, acid-base and pore characteristics can be tailored. Porous model materials serve to independently investigate transport limitations. Reactant complexity and reaction conditions are varied to ensure broad validity of the findings.” (July 2019)