(629am) Copper Based Plasmonic Catalyst for Efficient and Selective Epoxidation of Propene

Propylene oxide (PO) is a valuable commodity chemical to produce important products such as paints, cosmetics and adhesives, etc. It is commercially produced using liquid phase chlorohydrin or hydroperoxide routes. Each of these routes has inherent limitations owing to the undesired byproducts and high operating cost. Because of these limitations in the existing processes, the direct epoxidation of propylene to PO using a heterogeneous catalyst is the most desirable in view of environmental friendliness and operating costs, and it has been one of the most challenging tasks in catalysis. Additionally, the increasing energy demand in near future will force us to design chemical synthesis processes using renewable energy resources. Developing catalysts that can make use of renewable energy resources like solar energy to make desired valuable chemicals is of critical importance to meet this requirement.
In this contribution, we demonstrate that copper based catalyst exhibit high selectivity in epoxidation of propylene to form PO. We also demonstrate that copper nanostructure, characterized by strong plasmon resonance peak in the visible region, can be used to efficiently harvest visible light (with intensity on the order of solar intensity) and utilize it to drive propylene epoxidation at significantly lower temperature than the epoxidation under pure thermal conditions. Our current results show that copper can be used as highly selective and energy efficient catalyst for the direct epoxidation of propylene. These results gives an insight to design energy efficient catalytic processes with a significant fraction of energy input provided in the form of sunlight.