Structural features and adsorption behaviour of mesoporous silica particles formed from droplets generated in a spraying chamber

• Spherical mesoporous particles have been produced by spraying hydrolysed alkoxide solutions containing templating amphiphilic molecules. The modified spray drying method produces up to 10 g/h of spherical non-hollow particles with a size of 1–5 m. Transmission electron microscopy and X-ray diffraction showed that well ordered internal 2D hexagonal mesostructures could be prepared using both nonionic block copolymers and cationic surfactants as the templating molecules. Disordered cubic and well ordered lamellar, onion like, particles were prepared from the block copolymer templates. Nitrogen sorption data and mercury porosimetry show that pore size distribution of the mesoporous particles is very narrow with pore sizes varying from 2.5 to 8.5 nm as a function of templating amphiphiles. We have shown that the mesoscopic pores are accessible after calcination and can be filled with relatively large molecules; the particles adsorbed more than 20% (by weight) of the cationic dye Janus Green B from aqueous solutions.

Keyword

Mesoporous particles

spray drying

adsorption behaviour

Publication and Content Type

ref (subject category)

art (subject category)