In this work, an RF-Carbon Aerogel/Surface-grown 2D layered g-C3N4 heterojunction (CA/CN) was prepared using carbon aerogel (CA) and urea and was then utilized to remediate an aqueous medium polluted with ibuprofen. g-C3N4 (CN), carbon aerogel, and their composite were characterized by XRD, FTIR, TEM, N2 ads-des isotherm, DRS, PL, and zeta potential. The results revealed nanolayers of g-C3N4 grown in cluster form on the CA surface, transforming its nitrogen physisorption isotherm to type I, while CA and CN had type IV and V, respectively. Besides, due to the effective heterojunction formation of g-C3N4 with carbon aerogel, the CA/CN band gap was reduced from 2.8 eV (for CN) to 2.61 eV. CA/CN showed 14-fold higher activity toward the elimination of ibuprofen compared to CA and CN materials. Furthermore, optimization of process variables (pH, ibuprofen initial concentration, and photocatalyst dosage) was accomplished using Design-Expert software. Based on the results, a second-order nonlinear model was fitted using the response surface method (central composite design), and pH was identified as the most effective variable based on variance analysis. In optimal operating conditions, with pH = 4.6 ± 0.5, photocatalyst dosage of 1.64 g/L, and pollutant concentration of 8 mg/L, 97 % ibuprofen and 59 % TOC removal efficiency was achieved.

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