Phenol removal using granular activated carbon from dates stones by H3PO4 activation

Granular activated carbon (GAC) was produced from dates stones (DS) by chemical activation using H 3 PO, as activator. The effects of preparation conditions (carbonisation temperature (CT) = 500, 600 and 700 degrees C, carbonisation time (Ct) = I and 3 h and R the ratio of activator to dry dates stones = 0.5 and 2) on the yield, particle size distribution, and phenol removal ability of the produced GAC were explored. A better fitting of the phenol adsorption data was achieved using the Freundlich isotherm equation compared to the Langmuir adsorption equation. The optimum conditions selected based on phenol adsorption are: CT = 600 degrees C, Ct = 3 h and R = 0.5 with maximum adsorption capacity of phenol = 75.32 mg/g. The yield of GAC under these conditions was 49.1% with 80% of the produced GAC particles are between 1.2 to 2.18 mm. Laboratory scale packed bed adsorption experiments could be very well fitted using a dispersed plug flow model especially for the combination of low flow rate and long bed models. Under different conditions, however, deviations from this model were observed at longer operating times where pore diffusion seems to be the controlling mechanism.