Nanoscale dispersion of palygorskite bundles by a facile mechanical/chemical approach

Abstract

In this paper, we developed a simple mechanical/chemical process to efficiently disperse palygorskite (PAL) crystal bundles into individual nanorods. The “cavity effect” of high-pressure homogenization process generated many “Miniature bombs” in the interior gap of crystal bundles, which may mildly “blast” and effectively burst through the hugged PAL rod crystals without losing their original aspect ratio. Sodium metaaluminate (SM) was simultaneously introduced in the high-pressure homogenization process to promote the dispersion of crystal bundles and restrain the re-aggregation of dispersed nanorods. The dispersion degree and surface charge of PAL nanorods were greatly improved, and the colloidal viscosity of aqueous suspension of highly dispersed PAL rods greatly enhanced by 148% in contrast to raw PAL aggregates. Also, the colloidal stability and rheological properties of PAL were clearly improved after dispersion. As a whole, this process can produce PAL nanorods in an industrial scale, which opens a new avenue to extend the application of PAL in many industrial areas such as fine chemicals, functional carriers and nanocomposites. Copyright © 2018 VBRI Press.