A novel oxidation–reduction method for efficient synthesizing <i>tert</i> ‐butylhydroquinone based on the combination of microchannel reactors and batch reactors

Abstract Tert ‐butylhydroquinone (TBHQ) is a highly efficient and stable food additive with significant demand. However, traditional synthesis methods are associated with issues such as environmental pollution and low product selectivity. Herein, a novel process for the highly selective synthesis of TBHQ by oxidation–reduction method from 2‐ tert ‐butylphenol (2‐TBP) was proposed. The 2‐ tert ‐butyl‐1,4‐benzoquinone (2‐TBQ) yield was approximately 61.7% obtained within 11.02 min in a microchannel reactor. In the subsequent hydrogenation step, a high TBHQ yield of 98.0% was achieved with a high selectivity of 98.4%, while the selectivity was 77.0% by using the traditional process. Moreover, by introducing the theory of intermolecular hydrogen bonding, it was discovered that the strength of hydrogen bonds was positively correlated with the colour depth of the solutions. CFD simulations results shows that a stirring rate of 600 rpm could provide sufficient vertical momentum for effective gas–liquid–solid mixing and ensure uniform dispersion of catalyst.