Efficient absorption of ibuprofen in aqueous solution using eco-friendly C3N4/soot composite

The removal of ibuprofen (IBP) from wastewater is a hot topic in both academic and industrial fields. Herein, we reported a novel eco-friendly absorbent C3N4/soot composite via a simple one-step pyrolysis process, which had high adsorptive activity for the removal of IBP from wastewater. Adsorption kinetic and isotherm data of the adsorption process were investigated. The adsorption capacity at room temperature for low equilibrium concentration (10 mg/L) was as high as 104 mg/g, which was very similar to the maximum adsorption capacity (148.81 mg/g). The pseudo-first-order, pseudo-second-order, and the intraparticle diffusion models could best describe adsorption kinetics of IBP on 7 wt% C3N4/soot, and adsorption isotherm is well fitted to Langmuir model. Thermodynamic parameters (Delta H, Delta G, and Delta S) indicated that IBP adsorption on C3N4/soot composite was spontaneous and endothermic. Moreover, the potential adsorption mechanism of C3N4/soot composite for the adsorption of IBP was proposed. The 7 wt% C3N4/soot composite exhibited much higher adsorptive activity and still showed a relatively high adsorption stability even after five cycles, which were potentially suitable for high efficiency and low-cost water purification.