Response surface methodology approach of phenol removal study using high-quality activated carbon derived from H3PO4 activation of Acacia mangium wood

This study investigated the efficiency of phenol removal and adsorption capacity of high-quality Acacia mangium wood activated carbon (AMW-AC) (BET surface area, 1767 m2/g) prepared from activation of H3PO4 under optimal conditions of activation temperature (900 °C), activating agent concentration (40 %), and activation time (45 min). A face-centered central composite design (FCCD) of the response surface methodology (RSM) was applied to create a set of experiments for phenol removal. The effects of independent variables, such as solution temperature, contact time, initial phenol concentration, and solution pH, were observed on the phenol removal percentage and the adsorption capacity of AMW-AC. Analysis of variance data suggested quadratic models with significant p-values (<0.0001) for responses (phenol removal percentage and adsorption capacity of AMW-AC). The contact time and the solution pH were significant for the percentage of phenol removal, whereas contact time, initial phenol concentration, and solution pH are highly significant for the adsorption capacity of AMW-AC. The maximum percentage of phenol removal (73 %) with the highest adsorption capacity (53.8 mg/g) obtained through a face-centered central composite design of experiment was at solution temperature 25 °C and contact time 138 min for 150 ppm initial phenol concentration and solution pH 3.0. The statistical data revealed that Acacia mangium wood waste has the potential to be converted into a highly efficient adsorbent (activated carbon through chemical activation with phosphoric acid) for effectively removing phenol from wastewater.