(6bq) Preparation of Multimetallic Catalytic Systems By Controlled Surface Reactions for Biomass Upgrading

Supported multimetallic catalysts are an important class of materials owing to their enhanced activity, selectivity and stability that surpasses their monometallic counterparts. The enhanced performance of these multimetallic catalysts can be due to synergistic effects between the constituent metals, achieved when these metals are in close proximity. Moreover, achieving a narrow distribution of structures and compositions during the preparation of these multimetallic catalysts is critical in understanding structure-property relationship of these materials and is important for improving their design and function. Preparing such a multimetallic catalyst has proven to be a challenging task. My experience and skill in preparing such a muticomponent system puts me in a unique position to synthesize novel materials for a variety of contemporary applications, including design of heterogeneous catalysts for upgrading biomass-derived compounds to value added chemicals.

I started working on bimetallic catalysts during my PhD research in the Department of Chemical Engineering, Middle East Technical University (Ankara-Turkey), under the supervision of Prof. Timur Dogu and co-supervision of Prof. Gulsen Dogu of Gazi University (Ankara-Turkey). My thesis was based on the development of active and stable bimetallic catalysts for steam reforming of ethanol for hydrogen production.

As a visiting scholar at the Iowa State University, I worked on a collaborative project between Prof. Brent Shank's Group and Prof. James A. Dumesic's Group. In this collaborative project, I synthesized bifunctional SBA-15 supported catalysts comprising of both acidic and basic sites. In parallel, I also worked on synthesizing a hydrophobic, SBA-15 supported Pt catalyst for the production of hydroxymethylfurfural (HMF) from glucose in a biphasic system.

During my postdoctoral research with Prof. James A. Dumesic, I worked on diverse projects including both homogeneous and heterogeneous catalysis. I worked on understanding the kinetics of dehydration of the hemicellulose fraction of biomass, primarily xylose, using a biomass-derived solvent, gamma-valerolactone (GVL), and I investigated the hydrogenation of furfural to form furfuryl alcohol with copper based catalysts which where stabilized by atomic layer deposition of MgO_x and AlO_x.

During my tenure as a post-doctoral researcher, I developed new methods for synthesizing supported bimetallic catalysts using controlled surface reactions (CSR). I prepared and characterized bimetallic catalysts by a new synthesis protocol developed in our group, and I studied these catalysts for hydrogenolysis of 2-(hydroxymethyl)tetrahydropyran ¹. I also worked on using these well-defined and characterized catalysts to study their improved activity for industrially relevant reactions, including the water gas shift reaction and higher alcohol synthesis from syngas. Currently, I am using the CSR technique for the synthesis of ternary systems.

During my graduate studies in the Department of Chemical Engineering at the Middle East Technical University, I worked extensively as a teaching assistant. I was a teaching assistant for all of the core chemical engineering courses both at the undergraduate and graduate levels (Chemical Process Calculations, Fluid Mechanics, Chemical Reaction Engineering, Thermodynamics, Mass Transfer and Separation Processes, Heat Transfer, Reactor Design, etc.) and chemical engineering laboratory courses (Chemical Engineering Laboratory I-II). I also mentored undergraduate students working in our group for their research projects. During these teaching assistantship experiences, I always enjoyed teaching and simultaneously learning from these enriching experiences.

For my future career, the ultimate goal of my research is to use my experience in synthesis and characterization of heterogeneous catalysts. Developing the CSR technique was important because conventional synthesis methods for the preparation of bimetallic catalysts can complicate the analysis of experimental data to elucidate the nature of the active sites. The procedure is well-suited for extension to ternary systems that can potentially enable us to bring together less compatible components for catalytic property enhancement. These materials are also ideal for comparison with theoretical studies targeted for discovery, development and understanding of supported bimetallic catalysts. Relevant reactions for producing value added chemicals from biomass derived compounds are hydrogenolysis of polyols, hydrodeoxygenation of aromatic alcohols, and reduction of 3-hydroxypropionic acid to 1,3 propanediol.

Reference:

1. Hakim S.H., Sener C., Alba-Rubio A.C., Gostanian T.M., O’Neill B.J., Ribeiro F.H., Miller J.T., Dumesic J.A., “Synthesis of Supported Bimetallic Nanoparticles with Controlled Size and Composition Distributions for Active Site Elucidation”, Journal of Catalysis,328, 75-90 (2015).