Removal of bisphenol A (BPA) by fermented sludge-derived granular biochar from template-like method: From batch experiment to continuous operation

Endocrine disruptors have biological toxicity and can interfere with the endocrine system of organisms. They widely exist in natural water bodies. Here, the granular biochar was prepared from fermented sludge for the first time by using cationic polyacrylamide as template agent via a template-like method. The as prepared biochar was investigated for the removal of BPA in aqueous media by batch experiment and continuous flow experiment. The pyrolysis temperature and template concentration had a great influence on the properties of residual biochar and BPA capture. The static adsorption results show that when the template concentration was 1% with the pyrolysis temperature of 800 degrees C, the optimal biochar P-1%- 800 achieved the BPA adsorption value up to 84.78 mg/g. Its adsorption behavior, influencing factors, and recycling capability on BPA reduction were evaluated. Kinetics, isotherms and characterization analysis suggested that the adsorption mechanism involved pore filling, electrostatic attraction, pi-pi interactions and hydrogen bonding. Good regeneration performance, low concentration heavy metal leaching and lasting continuous flow stability in fixed-bed device under different water quality background demonstrated that fermented sludge-derived granular biochar P-1%- 800 is a desirable adsorbent for reducing BPA in complex water environment.