Journal of Sol-Gel Science and Technology

, Volume 89, Issue 2, pp 458–472 | Cite as

Effects of different parameters on the synthesis of silica aerogel microspheres in supercritical CO2 and their potential use as an adsorbent

  • Ersin Başaran
  • Tuğba Alp Arıcı
  • Adnan Özcan
  • Özer Gök
  • A. Safa ÖzcanEmail author
Original Paper: Nano- and macroporous materials (aerogels, xerogels, cryogels, etc.)


Synthesis of metal oxide microspheres in supercritical carbon dioxide (SCO2) is very attractive for a wide range of applications such as catalysis, controlled release, and separation science due to their identical properties. The aim of this study is the synthesis of silica microspheres (SM) in SCO2 by sol–gel method. The effects of temperature, pressure, flow rate, time, co-solvent and its ratio on the synthesis of silica microspheres in SCO2 were investigated. The synthesized microspheres were characterized by several techniques including field emission scanning electron microscopy (FE-SEM), Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), dynamic light scattering (DLS), and surface area analysis. The results indicated that the optimum condition for the synthesis of SM was determined at 150 bar, 80 °C, and 2.5 mL min−1 of SCO2 flow rate. The usability of SM as an adsorbent for the removal of dyes and heavy metals from aqueous solutions was also examined. Kinetic and isotherm studies for the adsorption of Pb(II) ions and Acid Blue 260 (AB260) onto SM were carried out.


Silica Microspheres Supercritical CO2 Characterization Adsorption 



The authors gratefully acknowledge the financial support provided by Anadolu University for the Scientific Research Projects (Project Nos.: 1306F256 and 1401F011).

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.


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Authors and Affiliations

  • Ersin Başaran
    • 1
  • Tuğba Alp Arıcı
    • 2
  • Adnan Özcan
    • 1
    • 3
  • Özer Gök
    • 1
    • 3
  • A. Safa Özcan
    • 1
    • 3
    Email author
  1. 1.Department of Chemistry, Faculty of ScienceEskişehir Technical UniversityEskişehirTurkey
  2. 2.Department of Chemical Technology, Emet Vocational SchoolKütahya Dumlupınar UniversityKütahyaTurkey
  3. 3.Department of Chemistry, Faculty of ScienceAnadolu University26470 EskişehirTurkey

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