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Production of porous silica microparticles by membrane emulsification

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journal contribution
posted on 10.02.2012, 14:27 by Marijana Dragosavac, Goran Vladisavljevic, Richard Holdich, Michael T. Stillwell
A method for the production of near-monodispersed spherical silica particles with controllable porosity based on the formation of uniform emulsion droplets using membrane emulsification is described. A hydrophobic metal membrane with a 15 μm pore size and 200 μm pore spacing was used to produce near-monodispersed droplets, with a mean size that could be controlled between 65 and 240 μm containing acidified sodium silicate solution (with 4 and 6 wt % SiO2) in kerosene. After drying and shrinking, the final silica particles had a mean size in the range between 30 and 70 μm. The coefficient of variation for both the droplets and the particles did not exceed 35%. The most uniform particles had a mean diameter of 40 μm and coefficient of variation of 17%. By altering the pH of the sodium silicate solution and aging the gel particles in water or acetone, the internal structure of the silica particles was successfully modified, and both micro- and mesoporous near-monodispersed spherical particles were produced with an average internal pore size between 1 and 6 nm and an average surface area between 360 and 750 m2 g–1. A material balance and particle size analysis provided identical values for the internal voidage of the particles, when compared to the voidage as determined by BET analysis.

History

School

  • Aeronautical, Automotive, Chemical and Materials Engineering

Department

  • Chemical Engineering

Citation

DRAGOSAVAC, M.M. ... et al., 2012. Production of porous silica microparticles by membrane emulsification. Langmuir, 28 (1), pp. 134 - 143

Publisher

© American Chemical Society

Version

AM (Accepted Manuscript)

Publication date

2012

Notes

This document is the unedited author's version of a Submitted Work that was subsequently accepted for publication in Langmuir, copyright © American Chemical Society after peer review. To access the final edited and published work, see http://pubs.acs.org/doi/abs/10.1021/la202974b

ISSN

0743-7463;1520-5827

Language

en

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