Textural properties of activated carbons from apricot stones

Chemically activated carbons were prepared from apricot stones. Phosphoric acid (25-75 wt.%) was used as an activating agent at 400-600 °C. Zinc chloride-activated carbon were also prepared at 600 and 700 °C using three different zinc chloride:apricot stone ratios of 0.5, 1.0 and 2.0. Steam-activated carbons were obtained by gasifying un-activated carbon obtained by carbonizing apricot stones, at 900 °C to burn-off 25 and 35%. The textural parameters were determined from the nitrogen adsorption data at 77 K. Different adsorption models were considered for the analysis of the adsorption results. Considerable differences between surface areas and pore volume as obtained by considering the different models, have been observed. However, the method of analysis based on comparing the isotherm determined for a given active carbon with the standard isotherm for a non-porous adsorbent seems to be trustworthy.