Fluidization of mixed SiO2 and ZnO nanoparticles by adding coarse particles

•The behavior of mixed nanoparticles can be improved by adding coarse particles.•The minimum fluidization velocities can be decreased by adding coarse particles.•The R–Z exponents can characterize the fluidization behavior of binary mixtures.

Fluidization behavior of binary mixed SiO2 and ZnO nanoparticles by adding 3 different fluid catalytic cracking (FCC) or Al2O3 coarse particles was studied. The Richardson–Zaki exponents of the single and binary mixtures were calculated by using linear regression. The results showed that the improvement of the fluidization behavior of mixed nanoparticles by adding Al2O3 coarse particles was not obvious. Fluidization behavior of mixed nanoparticles can be improved significantly by adding FCC coarse particles. However, the effect of adding FCC2 (61–90 μm) and FCC3(38–61 μm) coarse particles is better than that of adding FCC1(90–109 μm) coarse particles. The order of degree of agglomerate particulate fluidization of beds by adding the same amount of FCC coarse particles is pure SiO2, 70% SiO2 and 30% ZnO, 50% SiO2 and 50% ZnO, 30% SiO2 and 70% ZnO and pure ZnO nanoparticles.

Graphical abstractFig. 12 Agglomerate sizes of mixed nanoparticles by adding FCC coarse particles. (The ratio in the fig is mass ratio.).Figure optionsDownload full-size imageDownload as PowerPoint slide