Carbon Aerogels as Catalyst Supports
M. Stolarski, K. Brodzik, J. Walendziewski, R. LuВїny and E. Broniek
Wroclaw University of Technology, Faculty of Chemistry,
Department of Fuels Chemistry and Technology, Ul. Gdañska 7/9, 50-344 Wroclaw (Poland)
E-mail: jerzy.walendziewski@pwr.wroc.pl
Аннотация
Influence of the process parameters on porous structure of monolithic and spherical resorcinol-formaldehyde (RF) carbon aerogels prepared by supercritical acetone and carbon dioxide drying of alcogels, followed by carbonization is presented. The prepared organic RF aerogels were carbonized at 600 oC to form carbon aerogels and their porous structure was characterized by nitrogen adsorption. It was stated that synthesis parameters of RF organic aerogels (catalyst type, gel curing time, R/C ratio, resorcinol concentration in water) and drying method (low- or high-temperature supercritical drying) strongly influence textural parameters of the final carbon aerogels. Application of KOH in RF aerogel preparation allows obtaining carbon aerogels of the most advantageous parameters irrespective of the used drying method. Elongation of curing time of RF gels results in an increase in specific surface area and total pore volume of the carbon aerogels obtained both in the course of low- and high-temperature drying. Low-temperature supercritical drying of RF aerogels gives carbon materials of more advantageous texture parameters in comparison to carbon aerogels obtained in high-temperature supercritical drying.
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