Powerful scalable photochemistry: the efficient use of light

corresponding

GUILLAUME GAURON*, JIE AO, SYLVAIN GREMETZ, CLEMENS R. HORN
*Corresponding author
Corning S.A.S., Corning European Technology Center, Avon Cedex, France

Abstract

Photo flow chemistry has become a very popular field of research. This work demonstrates that the recognized mass transfer and heat management of microreactors are superior to simple-tubular reactors commonly used in photo chemical research. Additionally, the benefit of using Light Emitting Diodes (LED) as a clean and efficient light source is shown by demonstrating the effect of two different light wavelengths on a reaction. The combination of a structured flow reactor and LED light source provides an efficient flow reactor that can also be scaled up.


INTRODUCTION

Flow Chemistry is now a well-understood technology in many parts of the chemical industry (1, 2). Major sectors such as agrochemicals, fine chemicals, and pharmaceuticals have started the shift from batch to continuous processing. Among the factors driving the change are the need for safer and “greener” chemical processes, the need to accelerate and shorten the development-to-production cycle, and the need for cost-efficient processes. Despite these compelling drivers, the shift from batch to flow was difficult for the early-adopters. But that has changed. Flow chemistry technology and implementation have improved sufficiently that flow processes are now competitive with well established, low-cost batch facilities.

The Booker-Milburn (3) paper led to a renaissance in photo chemistry research (4, 5, 6). The authors demonstrated that wrapping a plastic tube around a light source was a simple and rapid way to create a flow reactor. Simplicity, however, has its drawbacks. The benefits of state-of-the-art micro reactor technology are less exploitable in those simple reactors. For example, the mass transfer is limited when one us ...