Organic Reactions Catalyzed by Enzymes and DNA-Based Hybrid Catalysts
The fundamental understanding of enzyme behaviors in different solvent systems can further guide the use of biocatalysis in many organic reactions. We are particularly interested in understanding the mechanisms of enzyme-catalyzed reactions in non-aqueous media (such as ionic liquids, deep eutectic solvents, and glymes), as well as the preparation of new enzyme-compatible solvent systems. In addition, we are interested in new hybrid catalysts prepared by binding metal complexes with DNA molecules as chiral scaffold. These hybrid catalysts can be widely used in the asymmetric synthesis of Michael addition, Diels-Alder reaction and Friedel-Crafts alkylation.
Synthesis of Polyesters and Their Derivatives via Enzymatic Polymerization
Polyesters, such as polylactides (PLAs) and polylactones, are sustainable and biodegradable polymers with a wide range of applications in packaging, horticultural materials, and biomedical fields. These polyesters can be prepared by various chemical methods such as polycondensation and ring-opening polymerization (ROP). Our group is interested in a more benign approach of using enzymatic ring-opening polymerization (ROP) to synthesize these polyesters and polyester-grafted nanocellulose materials.
Deep Desulfurization of Liquid Fuels by Oxidative Extraction Using Ionic Liquids
Since 2005, more stringent regulations have been enforced to reduce the sulfur content for gasoline and diesel oil to 10-30 ppm level. To meet this ultra-low sulfur limit, the conventional hydrodesulfurization (HDS) method is not always efficient, particularly in removing aromatic sulfur compounds such as benzothiophene (BT), dibenzothiophene (DBT), and their alkyl derivatives. Among many alternative deep desulfurization approaches, oxidative extraction using ionic liquids (ILs) has attracted remarkable attention due to the favorable properties of ILs such as low volatility, high solubility of sulfur compounds, high thermal/chemical stability, and tunable physical properties. Our group plans to synthesize inexpensive task-specific ILs that can efficiently remove aromatic sulfur compounds from fossil fuels.
Biocatalysis for Cellulosic Ethanol and Biodiesel Preparations
Cellulosic ethanol and biodiesel (fatty acid monoester) represent two important categories of renewable biofuels. We are interested in developing inexpensive solvent systems (including ionic liquids) for pretreating cellulosic biomass, and investigating the enzymatic hydrolysis and fermentation of pretreated lignocelluloses. In addition, our group is interested in developing inexpensive and novel deep eutectic solvents as reaction media for the enzymatic preparation of biodiesel from renewable lipid sources such as microalgae. We are also interested in exploring the chemical preparation of biodiesel using inexpensive ‘green’ solvents.
