Process optimisation of porous carbon preparation from date palm pits and adsorption kinetics of methylene blue

The present study focuses on the process optimisation of porous carbon preparation from date seed pits. The response surface methodology (RSM) technique with Box-Behnken method (BBM) was utilised with the response variables being the yield and BET surface area. The influencing parameters selected were activation temperature, impregnation ratio (IR) and activation time. The optimum conditions were identified to be an activation temperature of 500°C, IR of 2 and activation time of 75min, with the resulting yield and BET surface area being 46% and 838m²/g. The average pore volume and average pore diameter were 1.07cm³/g and 1.69nm, respectively. In order to assess the suitability of the carbon for adsorption of macromolecules, the kinetics of methylene blue (MB) adsorption were assessed by varying the initial concentration and the adsorption temperature. The kinetic parameters were evaluated applying the pseudo-second-order kinetic model by minimising the error between the experimental data and the model prediction; it was found to represent the experimental data more aptly.