Effect of Surface Characteristics on Fluidization Behavior of Hyrophilic Silica Nanoparticles

Impact of surface properties on the fluidization quality and Richardson-Zaki (R-Z) exponent of hydrophilic silica nanoparticle agglomerates in fluidized bed was investigated. It was demonstrated that the hydrogen bond plays a vital role in decreasing the interparticle force and, consequently, improves the quality of fluidization of hydrophilic silica. By adding isopropanol (ISP) to nanoparticles, hydrophilic silica behaved like hydrophobic silica and ABF fluidization turned into APF fluidization. ISP is an amphiphilic compound. Hydroxyl groups of ISP bond to the silicasurface and cover it by hydrocarbon groups and make the surface hydrophobe. As a result, the interparticle forces become weaker which leads to enhancement of fluidization quality. The R-Z exponent of nanoparticles in presence and absence of ISP was estimated by linear regression. It wasindicated that the particulate fluidization degree is related to the R-Z exponent. The APF fluidization has a greater R-Z exponent compared to the ABF fluidization.

کلیدواژه ها:

Nanoparticles ، Agglomerate ، Fluidization ، Richardson-Zaki exponent ، Isopropanol