ESTONIAN ACADEMY
PUBLISHERS
eesti teaduste
akadeemia kirjastus
PUBLISHED
SINCE 1984
 
Oil Shale cover
Oil Shale
ISSN 1736-7492 (Electronic)
ISSN 0208-189X (Print)
Impact Factor (2022): 1.9
LOW-DENSITY ORGANIC AEROGELS FROM OIL SHALE BY-PRODUCT 5-METHYLRESORCINOL; pp. 348–358
PDF | doi: 10.3176/oil.2008.3.06

Authors
A.-L. PEIKOLAINEN, F. PÉREZ-CABALLERO, M. KOEL
Abstract

The objective of the present work was to prepare organic aerogels using a by-product of oil shale processing as a starting material. Low-density organic aerogels were synthesized via sol-gel polycondensation of formal­dehyde (FA) and either 96% 5-methylresorcinol (MR) or the technical mixture named Honeyol™ (H) containing 59.6% of 5-methylresorcinol among other diphenolic compounds, using supercritical CO2 for drying the gel obtained. Porosity and particle characteristics of MR-FA and H-FA aero­gels can easily be controlled by varying the concentrations of precursors and preparation conditions. Less than 4.5-hour drying resulted in MR-FA aerogel characterized by radial shrinkage 2%, density 0.21 g/cm3 and specific surface area 350 m2/g. At the same molar ratios H-FA aerogel had 29% shrinkage, 302 m2/g specific surface area and the density as low as 0.10 g/cm3.

    The preparation techniques and morphology of MR-FA and H-FA aerogels were compared to resorcinol-formaldehyde, phloroglucinol-formaldehyde and phenol-formaldehyde aerogels.
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