Synergistic mechanisms for the superior sorptive removal of aquatic pollutants via functionalized biochar-clay composite

This study investigated the successful synthesis of functionalized algal biochar-clay composite (FBKC). Subsequently, the sorption performance of FBKC towards norfloxacin (NFX) antibiotic and crystal violet dye (CVD) from water was extensively assessed in both batch and continuous flow systems. A series of characterization techniques were carried out for FBKC and the utilized precursors, indicating that the surface area of FBKC was increased thirtyfold with a well-developed pore structure compared to the original precursors. FBKC demonstrated a maximum sorption capacity of 192.80 and 281.24 mg/g for NFX and CVD, respectively. The suited fitting of the experimental data to Freundlich and Clark models suggested multi-layer sorption of NFX/CVD molecules. The mechanistic studies of NFX/CVD sorption onto FBKC unveiled multiple mechanisms, including & pi;-& pi; interaction, hydrogen bonding, electrostatic attraction, and surface/pore filling effect. The estimated cost of 5.72 euro/kg and superior sorption capacity makes FBKC an efficient low-cost sorbent for emergent water pollutants.

Automated summary

This study successfully synthesized functionalized algal biochar-clay composite (FBKC) and extensively evaluated its sorption performance towards norfloxacin (NFX) antibiotic and crystal violet dye (CVD) in both batch and continuous flow systems. Characterization techniques showed that FBKC had a significantly increased surface area and well-developed pore structure compared to the precursors. FBKC exhibited a high maximum sorption capacity for both NFX and CVD, and the fitting of experimental data to Freundlich and Clark models suggested multi-layer sorption of NFX/CVD molecules. Mechanistic studies revealed multiple mechanisms involved in NFX/CVD sorption onto FBKC, and the estimated low cost and superior sorption capacity make FBKC an efficient sorbent for emergent water pollutants.