A Novel Nebulizer-Based Continuous Flow Reactor: Introducing the Use of Pneumatically Generated Aerosols for Highly Productive Photooxidations

A very effective and highly innovative continuous flow reactor (CFR) for undertaking important large-scale photooxidations is presented. Until now, two major issues have obstructed the widespread use of photooxidation CFRs: 1) the detrimental effect of poor oxygen solubility on the rate of biphasic gas–liquid reactions and 2) the rapid attenuation of light by solutions which severely limits dimension-enlarging opportunities. Both problems are nullified by this novel and yet extremely simple reactor design. The reactor operates by nebulizing a photooxidation solution inside a cylindrical chamber surrounded by a low-energy LED strip. Thus, the interfacial area between the two phases is maximized, leading to greatly improved reaction rates and excellent light penetration. This pneumatic nebulizer-based photooxygenation system (NebPhotOX) can use air (as the oxygen source) and very concentrated photooxidation solutions. NebPhotOX has very high productivity and could potentially be scaled up easily to work in an industrial setting.