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Granular activated carbons (>0.5 mm) have been prepared by KOH activation at 800 °C of cokes, size fraction of 0.63–1.25 mm, from high volatile bituminous coals. The most suitable coal is distinctive by the volatile matter content of about 33 wt.% and negative dilatation in the Audibert–Arnu test. The highest mechanical strength of granules is found for the activated carbons from cokes produced at 800–850 °C. They are microporous materials with porous texture parameters decreasing as the KOH/coke ratio varies from 4:1 to 2:1 in the range: surface area SBET 1800–1200 m2 g−1, micropore volume VDR 0.71–0.48 cm3 g−1 and mean micropore size L0 1.12–0.76 nm. The granular activated carbons represent interesting properties for gas adsorption application. CO2 uptake measured at 273 K amounts to 140 cm3 g−1 under atmospheric pressure and 370 cm3 g−1 under 3.5 MPa, corresponding to 6.2 and 15.7 mmol g−1, respectively. |
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