Adsorption Properties of Activated Carbons Prepared from Waste CDs and DVDs

Two sets of activated carbons have been prepared from waste CDs and DVDs by carbonization and subsequent activation with either KOH or CO2. The resulting activated carbons had specific surface area in the range of 500 2240 m2 g(-1), total pore volume in the range of 0.18-1.36 cm(3) CI, volume of micropores and small mesopores (w < similar to 2 nm) in the range of 0.17-1.25 cm3 g(-1), and volume of small micropores (w < similar to 1.2 nm) in the range of 0.14-0.71 cm3 g(-1). Both KOH and CO2 activation resulted in 5-4S-fold improvement in the structural properties, depending on the conditions used. The resulting carbons showed good adsorption properties toward carbon dioxide, hydrogen, and benzene. The best uptakes for these adsorptives were 5.8 mmol g(-1) of CO2 at 0 degrees C and 800 mmHg, 3.3 mmol g(-1) of CO2 at 25 degrees C and 850 mmHg, 13.9 mmol g(-1) of H-2 at 196 degrees C and 850 mmHg, and 15.4 mmol CI of C6H6 at 20 degrees C and saturation pressure. The excellent adsorption properties of the prepared carbons render them as potential adsorbents in CO2 capture and storage, VOCs adsorption/separation, and hydrogen storage.