混合纳米SiO2和纳米TiO2颗粒在添加FCC的流态化研究

混合纳米颗粒作为催化剂已经被应用于各工业领域。然而由于纳米颗粒的流态化性能较差,需要研究改善混合纳米颗粒流态化性能的方法。现阶段,国内外的研究大多集中在对单一纳米颗粒添加组分的流态化与混合纳米颗粒在外力场中的流态化,对混合颗粒添加组分的流态化未见报道。试验研究了纳米SiO2和纳米TiO2的混合组分在添加3种不同的FCC颗粒的流态化,为研究混合组分流化床中颗粒的碰撞、团聚和破碎机制提供实验基础。研究发现单纯的混合纳米颗粒难以流态化,添加FCC颗粒后其流态化性能有所提高,FCC颗粒对混合纳米颗粒流化性能的改善能力与其粒径和添加量有关。另外FCC2和FCC3颗粒对混合纳米颗粒的流化性能改善能力优于FCC1颗粒。相同添加量下,纯的SiO2流化性能最好,其余按由好到坏的顺序分别是w(SiO2):w(TiO2)=7:3,w(SiO2):w(TiO2)=5:5,w(SiO2):w(TiO2)=3:7以及纯的TiO2纳米颗粒。

Fluidization Behavior of Mixed SiO2 and TiO2 Nanoparticles with FCC Particles

Hybrid nanoparticles as catalyst are applied in various industrial fields. However, nano particle fluidization performance is poor, it is needed to study the improving method. At present, the research at home and abroad focuses mostly on fluidization of single nanoparticles by adding coarse particles and the fluidization of mixed nanoparticles in extra force fields, and there is no the report about fluidization of mixed nanoparticles with adding particles. Investigated the fluidization behavior of the mixture of SiO2 and TiO2 nanoparticles by adding 3 kinds of FCC coarse particles, and provided experimental basis for studying the mechanism of crashing, agglomerating and breaking among mixed nanoparticles. Found that the simple hybrid nanoparticles were difficult to be fluidized, and with adding coarse FCC particles, the fluidization behavior were obviously improved. The improving fluidization behavior of hybrid nanoparticles is related to the size and adding amount of FCC particles. In addition the fluidization effect of adding FCC2 and FCC3 coarse particles is better than that of adding FCC1 coarse particles. Under the same amount adding, the fluidization of pure SiO2 is best and the fluidization sequence from good to bad is w（SiO2）： w（TiO2）=7：3,w（SiO2）： w（TiO2）=5：5, w（SiO2）：w（TiO2）=3：7 and pure TiO2 nanoparticles.