N-doped carbon aerogels; pyrolysis; adsorption of metals; termogravimetry

N-doped carbon aerogels show some possibilities as material for sorption of metals. Resorcinol-formaldehyde aerogels (two samples without nitrogen, three sam-ples with addition of nitrogen containing precursors ? 3-hydroxypyridine, 3-aminophenol and melamine) were prepared in three steps: sol-gel polycondensa-tion, subcritical drying and pyrolysis. The aim of this contribution was to study the third step of preparation ? pyrolysis and to find any relation between pyrolysis and properties affecting adsorption. Pyrolysis was studied by non-isothermal TG in nitro-gen with constant heating rate, isothermal step at 500 °C was applied in some cases. Oxidation of organic gels in air was also tested. Besides expected correlation between the mass loss gained from TG and from heating in laboratory furnace, the relationship between the mass loss during pyrolysis and sorption capacities for Pb(II), Ni(II) and Cu(II) ions from aqueous solutions was found.