Investigation of Pyridine Synthesis in a Fast Fluidized Bed Reactor

Pyridine has been generally synthesized by aldehydes and ammonia in a turbulent fluidized bed reactor. In this paper, a fast fluidized bed reactor was proposed for pyridine synthesis. Experiment results show that the yields of pyridine and 3-picoline decrease while the selectivity of pyridine over 3-picoline is increased. A model was proposed to predict the performance of the fast fluidized bed reactor; the average prediction deviation is 6%. The influence of mass transfer, heat transfer, and backmixing of the gas phase is represented by a modification factor, and the mean value of this modification factor is 0.75 within the experimental operating conditions. By model prediction, the reaction should be terminated when the critical point of R2 is reached to avoid over-reaction. To optimize the pyridine and 3-picoline product yield and minimize coke product yield, the reaction temperature should be kept around 723 K.