Get access

Liquid Desiccant Solvent Extraction of Alumina-Filled Thermoreversible Gels

Authors

  • N. O. Shanti,

    1. Department of Materials Science and Engineering, Robert R. McCormick School of Engineering and Applied Science, Northwestern University, Evanston, Illinois
    Current affiliation:
    1. Member, The American Ceramic Society.

    Search for more papers by this author
  • G. C. DeNolf,

    1. Department of Materials Science and Engineering, Robert R. McCormick School of Engineering and Applied Science, Northwestern University, Evanston, Illinois
    Search for more papers by this author
  • K. R. Shull,

    1. Department of Materials Science and Engineering, Robert R. McCormick School of Engineering and Applied Science, Northwestern University, Evanston, Illinois
    Search for more papers by this author
  • K. T. Faber

    Corresponding authorCurrent affiliation:
    1. 3M Company, Maplewood, Minnesota
    • Department of Materials Science and Engineering, Robert R. McCormick School of Engineering and Applied Science, Northwestern University, Evanston, Illinois
    Search for more papers by this author

  • Member, The American Ceramic Society.
  • This work is supported by the MRSEC program of the National Science Foundation (DMR-0520513) at the Materials Research Center of Northwestern University. Portions of this work were performed in the Keck-II facility of the NUANCE Center and the Optical Microscopy and Metallography facility at Northwestern University, supported by NSF-NSEC, NSF-MRSEC, Keck Foundation, the State of Illinois, and Northwestern University.

Author to whom correspondence should be addressed. e-mail: k-faber@northwestern.edu

Abstract

A liquid desiccant solvent extraction technique is introduced to significantly reduce the amount of warping during drying in thermoreversibly gelcast alumina samples by eliminating capillary stresses during the initial solvent removal stage. This process is combined with a secondary drying step in a vacuum oven with an in-line solvent trap, allowing for the complete recovery of the alcohol solvent used in producing gels. Optimal concentrations and immersion times for poly(tert-butyl acrylate)-based and water-based liquid desiccants are determined, along with the osmotic stresses and equilibrium solvent concentrations of gels immersed in these desiccants. Solvent loss during the liquid desiccant solvent extraction step, volumetric shrinkage during drying and sintering, and sintered porosity are measured. It is determined that a ~10 wt% poly(tert-butyl acrylate)/90 wt% isopropyl alcohol liquid desiccant is optimal.

Ancillary