Thermochimica Acta, Vol.614, 45-51, 2015
Effect of pyrolysis temperature and thermal oxidation on the adsorption properties of carbon cryogels
The effect of pyrolysis temperature (500 degrees C and 930 degrees C) and partial oxidation by oxygen (250 degrees C-450 degrees C) of resorcinol-formaldehyde cryogels (RF) and their graphene derivatives (RFGO) on adsorption capacity for Pb(II) and methylene blue were investigated. Increasing temperature of partial oxidation causes increase in adsorption capacity for Pb(II) from 0.09 to 0.20 (RF) and 0.10 to 0.29 mmol g(-1) (RFGO) for samples pyrolysed at 500 degrees C resp. from 0.20 to 0.23 (RF) and 0.16 to 0.27 mmol g(-1) (RFGO) for samples pyrolysed at 930 degrees C. Partial oxidation does not affect adsorption capacity for methylene blue. The adsorption capacity of carbon cryogels for both adsorbates increased with higher pyrolysis temperature about 90% for RF and 60% for RFGO. The presence of graphene in the structure does not improve the adsorption properties of prepared carbon cryogels. (C) 2015 Elsevier B.V. All rights reserved.