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Nanoparticle suspensions have been extensively applied in microfluidic processes. However, researchers paid little attention to the micromixing performance of this kind of system. In this work, the micromixing performance of nanoparticle suspensions in a micro-sieve dispersion reactor was investigated with the Villermaux/Dushman method. The effects of physical properties (density and viscosity), flow velocity and particle concentration were systematically studied by using two kinds of nanoparticles, SiO 2 and BaSO 4 . The results presented an efficiently enhanced mixing performance by nanoparticles, especially when the segregation index X S was larger than 10 −3 . Compared to the dispersed fluid, a better mixing performance could be achieved to suspend nanoparticles in the continuous fluid. A mathematical model based on Brownian movement of nanoparticles has been established to predict micromixing performance in the micro-sieve dispersion reactor. This study may provide some valuable information for the application of nanoparticle suspensions in microreactors.

In this work, porous glass beads supported with TS-1 particles have been successfully prepared through in situ crystallization. TS-1 particles with uniform size and high crystallization are well dispersed on the surface of porous glass beads. As the support, porous glass beads exhibit the advantages of more manageable surface chemistry, better chemical and thermal stability, and larger specific surface area compared to that of conventional TS-1 films on flat or tubular supports. The experimental results show that the surface chemistry has profound influence on the morphology of TS-1 particles. The catalytic performance of the material was characterized with the reaction of ammoximation of cyclohexanone. Complete conversion was reached after 20 min in a stirred tank reactor with the selectivity of 100%. Compared with the commercial catalyst, the reaction rate was increased by 54 times. The prepared catalysts were packed in a bed reactor, and the effects of space time, content of catalyst, temperature and pressure were investigated. The conversion of 48.1% was reached by the catalyst with TS-1 loading of 0.183 wt.% at 353 K and the space time of only 1.57 min, and 100% recovery in catalytic activity after 5 cycles was demonstrated.