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.
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