Continuous flow synthesis of zeolite FAU in an oscillatory baffled reactor

Abstract

In this work, we report, for the first time, the continuous flow synthesis of zeolite NaX successfully accomplished in a pilot-scale (up to 100 L/h) continuous oscillatory baffled reactor (COBR). The continuous synthesis was achieved by combining the seed-assisted method, in-line mixing of reactants at high temperature and COBR. The use of a COBR not only allowed the same residence time as the batch system, but also a controlled temperature profile, thanks to the plug flow behavior and effective heat transfer. A stable continuous operation was maintained during 5 hours owing to an effective mixing, preventing any hydrodynamic failure caused by the sedimentation of zeolite crystals. The results showed that zeolite NaX was obtained after 99 minutes and crystals between 0.6 and 0.7 μm were observed by scanning electron microscopy. The effect of frequency and amplitude on crystal properties was assessed. Sampling at three points along the COBR allowed the study of steady states of the zeolite concentration in temporal and spatial domains.continuous oscillatory baffled reactor, continuous zeolite synthesis, NaX zeolite, reactive heating crystallization

Special issue covering the Second International Process Intensification Conference (IPIC2)

“…The production on the lab and on the mini‐pilot scale are assessed, and the analysis revealed that the obtained yield in the cycloaddition step is the major factor influencing the environmental impact and cost of production. Lutz et al 8 employed an oscillatory baffled reactor for the continuous synthesis of zeolites, which enabled pilot‐scale production with a throughput of up to 100 L/h. The use of the oscillatory baffled reactor also prevented the sedimentation of the crystals, thus enabling stable long‐term continuous operation.…”