Multi-injection microstructured reactor for intensification of fast exothermic reactions: proof of concept

• Main Authors: Haber Julien, Jiang Bo, Maeder Thomas, Renken Albert, Kiwi-Minsker Lioubov
• Format: Article
• Language: English
• Published: De Gruyter 2013-10-01
• Series: Green Processing and Synthesis
• Subjects: exothermic; microstructured reactor; multi-injection; pseudoionone; temperature
• Online Access: https://doi.org/10.1515/gps-2013-0060

Quasi-instantaneous exothermic reactions lead to the formation of unwanted hot spots even when carried out in conventional microstructured reactors (MSR) with tube diameter of 100–1000 μm. For this reason, alternative MSR designs are warranted to enable process intensification of fast reactions with characteristic reaction times <1 s. The continuous multi-injection MSR, where one of the reactants is successively added to the main flow of reactants along reactor length, may improve temperature control. The latter was studied first theoretically using numerical simulations and then experimentally with the cyclisation of pseudoionone to α- and β-ionones as a model reaction. The multi-injection MSR made of low temperature co-fired ceramics (LTCC) led to a yield of α-ionone and β-ionone >0.98 reaching a 500-fold process intensification as compared to the conventional semi-batch process. The temperature profiles monitored by quantitative infrared thermal imaging confirmed an 8-fold reduced temperature rise compared to adiabatic temperature rise, which was achieved by injecting the reactants at three different injection points.