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.

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Synthesis of poly (1, 4-phenylene sulfide) (PPS) through oxidative polymerization seems promising to us. Comparing with current commercial method to poly (1, 4-phenylene sulfide) from 1, 4-phenylene sulfide and sodium sulfide (Phillips’ Method), there are many advantages of the oxidative polymerization method. For example, it can synthesize PPS at normal temperature and pressure; the yield of reaction is very high; it provides pure PPS without salt contamination. However, several years have passed away; synthesis of poly (1, 4-phenylene sulfide) through oxidative polymerization has not so far been adopted as the industrial process. Many of us are puzzled, why? Through studying all kinds of reported preparation route to poly (1, 4-phenylene sulfide) through oxidative polymerization compared to Phillips’ Method, a generic polymerization mechanism is achieved for most of them excepting two with obvious shortcomings. We suddenly realize that synthesis of poly (1, 4-phenylene sulfide) through oxidative polymerization seems unsuitable to be used in industrial production recently because of its own limits.

Thermal fragmentation process plays a key role in Fuel Coolant Interaction (FCI) during NPP's severe accidents, which significantly affects the heat transfer and determines the ratio of heat transferred to mechanical energy. Although various thermal fragmentation models have been raised, the phenomenon is not well understood due to its complicated process. Unstable film boiling is one of the mechanisms that lead to thermal fragmentation of the melt. In this paper, thermal fragmentation process induced by unstable film boiling condition is discussed based on theoretical analysis, including a momentum equation for vapor film dynamics, an energy equation for each phase involved and some appropriate boundary conditions. The effects of the initial melt temperature, coolant temperature and ambient pressure on thermal fragmentation process are also investigated. In order to evaluate this fragmentation model, a set of experiments on typical simulant materials are introduced, which give the fragmentation time and the evolution of mixture region. The evaluation shows that the main results calculated from the model are consistent with the experimental data and reflect the fragmentation process well.