Authors:María José Nieves-Remacha and Klavs F. Jensen
Ozonolysis of alkenes in liquid phase is conducted from micro scales to milli scales using a multichannel microreactor, a Corning low-flow reactor (LFR), and a Corning advanced-flow reactor (AFR). For the mass transfer limited test case of ozonolysis of 1-decene, maximum conversions that depend on the ozone availability in the gas phase are achieved regardless of the operating conditions, proving an excellent mass transfer in all three reactors. Ozonolysis of Sudan Red 7B dye provides visualization of the completion of the reaction in the glass-made AFR and LFR. Overall mass transfer coefficients are estimated to be on the order of 1/s in both the LFR and AFR, increasing with both liquid and gas flow rates. These values are within the same range observed in microchannels and one order of magnitude larger than in other conventional contactors.
Authors:Ketan Pimparkar, Bernard Yen, John R. Goodell, Veronique I. Martin, Wen-Hsuan Lee, John A. Porco Jr., Aaron B. Beeler and Klavs F. Jensen
In an effort to utilize microfluidics to enable photochemistry, we have devised a method for fabrication of devices with UV-transmissive glass. The photochemical device is successfully incorporated into a system utilizing high-pressure capillary mercury lamps and cooling system. We have demonstrated the ability to carry out photochemical transformations with substantial rate acceleration. Furthermore, we highlight the ability to carry out analytical-scale reactions on a pulse flow automated system while modulating wavelength and residence time to identify optimal photochemical reaction conditions. The analytical conditions were also successfully converted to continuous-flow preparative scale.