Discipline: Biological Sciences
Subcategory: Climate Change
Angel Noel Santiago Colon - University of Puerto Rico- Mayaguez
Co-Author(s): Siddarth Krishna, University of Wisconsin-Madison, Wisconsin Paolo Cuello, University of Wisconsin-Madison, Wisconsin James A Dumesic, University of Wisconsin-Madison, Wisconsin George W Huber, University of Wisconsin-Madison, Wisconsin
Biomass-platform molecules, such as Levoglucosenone (LGO), have been researched for practical purposes to produce highly valued chemicals. LGO can be hydrogenated into Cyrene (dihydrolevoglucosenone), a non-toxic solvent with similar properties to environmentally harmful solvents such as N-methylpyrrolidone . Stereoselectivity in the bio renewable Cyrene hydrogenation over supported Palladium catalyst have been studied but has not been completely understood. Practical motivation to studying stereoselectivity in this reaction is that It affects stereoselectivity of downstream valuable products such as 1,2,5,6-hexanetetrol. This work focuses on stereoselectivity of Cyrene hydrogenation to levoglucosanol (Lgol) over Pd/C and Pd/Al2O3 catalyst observing multiple factors in order to control the selectivity of Lgol diastereoisomers. A chiral modifier, cinchonidine, and different feed concentrations were used to control and understand the stereoselectivity in this reaction. Hydrogenation reactions were carried out in a batch reactor while the analysis was done using a Gas Chromatography method. The cinchonidine modifier was observed to produce an increase in diastereoisomeric excess at dilute conditions on Pd/C catalyst, while on Pd/Al2O3 no promotional effect was observed. Increase in feed concentration was determined to affect the catalyst stability and activity properties as it was found that the Pd/Al2O3 catalyst suffers severe deactivation with these conditions. Catalyst deactivation characterization was done to understand the source of this result. Catalyst deactivation and modifiers mechanism are to be studied more thoroughly in order to obtain a practical method to produce Lgol and its downstream products with the chemical properties of interest.
: 1. Krishna, S.; McClelland, D.; Rashke, Q.; Dumesic, J.; Huber, G. Green Chem. Hydrogenation of levoglucosenone to renewable chemicals. (2017), 19, 1278.
Funder Acknowledgement(s): This material is based upon work supported by: -3M -Department of Energy. Would like to acknowledge Huber's research group, Summer Undergraduate Research Experience (SURE) program, and University of Wisconsin-Madison Graduate School.
Faculty Advisor: George W. Huber, firstname.lastname@example.org
Role: Throughout this research I was involved in its multiple phases. I was in charge of doing literature review to provide the correct experimental design. In addition, I carried out all reactions and analysis while reporting the results and conclusions to graduate students and lab's professor. At the end of the summer, I passed the project to another graduate student that will continue the research in this topic for his graduate projects.