Mixing immiscible liquids typically requires the use of auxiliary substances including phase transfer catalysts, microgels, surfactants, complex polymers and nano- particles and/or micromixers. Centrifugally separated immiscible liquids of different densities...

aWith increasing concerns for the environmental impact of chemical manufacturing, reagents and processes that align with the principles of green chemistry are essential. The fundamental oxidation of organic substrates is no exception and in this report three distinct modes of green oxidation are demonstrated in a vortex fluidic device (VFD) under continuous flow: aerobic oxidation, oxidation using chlorine bleach, and oxidation using hydrogen peroxide. The VFD, which is a thin film microfluidic platform, revealed clear advantages in these oxidations in comparison to traditional batch reactor processing: Efficient mass transfer of gases in the dynamic thin film increased the rate of aerobic oxidations, and the intense micromixing allowed multi-phase oxidations to proceed efficiently, obviating the need for organic solvents and phase transfer catalysts. In addition, the rapid dissipation of heat in the VFD also improved the safety profile and stereoselectivity for exothermic oxidations.

Exfoliation or scrolling of hexagonal boron nitride (h-BN) occurs in a vortex fluidic device (VFD) operating under continuous flow, with a tilt angle of À45 relative to the horizontal position. This new VFD processing strategy is effective in avoiding the build-up of material that occurs when the device is operated using the conventional tilt angle of +45 , where the h-BN precursor and scrolls are centrifugally held against the wall of the tube. At a tilt angle of À45 the downward flow aided by gravity facilitates material exiting the tube with the exfoliation of h-BN and formation of h-BN scrolls then optimized by systematically varying the other VFD operating parameters,including flow rate and rotational speed, along with concentration of h-BN and the choice of solvent. Water was the most effective solvent, which enhances the green chemistry metrics of the processing.