Preparation and characterization of activated carbon from date stones by physical activation with steam

Activated carbons are produced from wastes of Algerian date stones by pyrolysis and physical activation in the presence of water vapor into a heated fixed-bed reactor. The effect of pyrolysis temperature and activation hold time on textural and chemical surface properties of raw date stones and carbon materials produced are studied. As expected, the percentage yield decreases with increase of activation temperature and hold time. The characterization of carbon materials is performed by scanning electron microscopy (SEM). X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and nitrogen adsorption (BET). Results show the presence of cellulose and hemicellulose in the raw material, and the predominance of carbon and graphite after pyrolysis. Different oxygen-containing functional groups are found in the raw material while aromatic structures are developed after pyrolysis and activation. The best specific surface area (635 m² g⁻¹) and microporous volume (0.716 cm³ g⁻¹) are obtained when the date stones are grinded, pyrolysed at 700 °C under a 100 cm³ min⁻¹ nitrogen flow and then activated under water vapor at 700 °C for 6 h.