Microstructure and Properties of Nano-Silica Prepared from Diatomite
ZHAN Feng
LIAO Zhehui
LI Zhongjing
CHEN Nanchun
Abstract：A Na2SiO3 precursor solution is formed through low-temperature hydrothermal dissolution with NaOH,using natural inorganic mineral diatomite as the silicon source.Under varying concentrations of Na2SO4,nano-silica is prepared via sulfuric acid precipitation and acidification.The microstructure and properties of the synthesized nano-silica are analyzed comparatively using X-ray diffraction(XRD),scanning electron microscopy(SEM),infrared spectroscopy(FTIR)and BET analysis of the specific surface area.The results reveal that the prepared silica exhibits abundant surface hydroxyl groups,indicating the structural characteristics of centric diatoms have disappeared.Optimal performance is achieved at a Na2SO4 concentration of 0.14 mol/L,where the primary particles have an average diameter of 9.506 nm and a BET specific surface area of 211.39 m2/g.The DBP absorption value is 2.647 cm3/g.These properties meet the performance criteria for Class A nano-silica products as defined by China's chemical industry standard(HG/T3061-1999).
Keywords：Diatomiteprecipitated silicamicrostructure
Publication Date：2025-12-30
Online Publishing Date：2026-01-17(First online date of this platform, not the publication date of the document)
Pages：6( 24-29 )