Microstructural modification of diatomite by acid treatment, high-speed shear, and ultrasound

Three modification approaches including acid treatment, high-speed shear and ultrasound on the microstructure of diatomite were developed, in order to enlarge the pore size and decrease the bulk density of diatomite and then make diatomite more suitable to be catalyst carrier. The modification effects were investigated and the results indicated that all three approaches had significant cooperative effects on the modification of diatomite. Acid treatment could remove impurities, mainly metallic oxides, of diatomite due to the acid wash effect. High-speed shear and ultrasound were both able to dredge the clogged pores because of the strong centrifugal force in shear process and cavitation effect in ultrasound process resulting in the improvement of the pore size distribution and the remarkable decrease of the bulk density.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Three modification approaches on the microstructure of diatomite were developed. ► The approaches could improve pore size distribution and decrease the bulk density. ► Corrosion, centrifugal force and cavitation effect were the main mechanism.