Optimized preparation of Phragmites australis activated carbon using the Box-Behnken method and desirability function to remove hydroquinone

Abstract

In this study, preparation of Phragmites australis activated carbon (PAAC) was optimized and applied for the removal of hydroquinone from aqueous solution. The Box-Behnken surface design (33) was used to statistically visualize the interactions among microwave power (A), microwave radiation time (B) and the ingredient ratio (C) (H3PO4: P. australis powder, in g). The desirability function was utilized to simultaneously optimize the multi-response indicators. A regression analysis showed that the experimental data of BBD optimization experimental results fit well to a quadratic model. PAAC was characterized according to its morphology, structure and composition. Dynamic adsorption data showed that the best fit was obtained by a pseudo-second-order model and the Freundlich isotherm model. The maximum adsorption capacity for hydroquinone adsorption onto PAAC was 156.25 mg/g at 30 ℃ and the adsorption mechanism may be attributed to multi-layer surface and chemisorption via donor-acceptor and coupling interaction of the electron. The present study showed that PAAC has the potential for use as a biosorbent for the adsorption treatment of water pollutants.