Aerobic oxidation of 2‐tert‐butyl phenol within gas–liquid segmented flow: Mass transfer characteristics and scale‐up

Abstract Quantifying the mass transfer of gas–liquid segmented flow in practical reactions is of significant for the scale‐up design. However, there is a lack of theoretical guidance to predict operational conditions to meet required the mass transfer in a selective dimension‐enlarged microreactor. Herein, the oxidation of 2‐ tert ‐butyl phenol (2‐TBP) was performed in a selective dimension‐enlarged capillary microreactor of 4.35 mm i.d. and optimal operation conditions were obtained. A high 2‐ tert ‐butyl‐1,4‐benzoquinone (2‐TBQ) yield of 73% was achieved within 6 min. Moreover, a quantitative method to assess the mass transfer of gas–liquid segmented flow in practical reaction was developed by introducing a circulation frequency, f cir , which could provide theoretical guidance to predict operating conditions for the scale‐up production. The 2‐TBQ productivity is significantly increased from 0.0061 to 0.5068 kg/h, that is, an increase of 83 times, by selective dimension enlarging from 2 mm to 4.35 mm with predicted operating conditions.