Analysis of Photocatalytic Degradation of Phenol with Exfoliated Graphitic Carbon Nitride and Light-Emitting Diodes Using Response Surface Methodology

Abstract

Response surface methodology (RSM) involving a Box–Benkhen design (BBD) was employed to analyze the photocatalytic degradation of phenol using exfoliated graphitic carbon nitride (g-C3N4) and light-emitting diodes (wavelength = 430 nm). The interaction between three parameters, namely, catalyst concentration (0.25–0.75 g/L), pollutant concentration (20–100 ppm), and pH of the solution (3–10), was examined and modeled. An empirical regression quadratic model was developed to relate the phenol degradation efficiency with these three parameters. Analysis of variance (ANOVA) was then applied to examine the significance of the model; this showed that the model is significant with an insignificant lack of fit and an R2 of 0.96. The statistical analysis demonstrated that, in the studied range, phenol concentration considerably affected phenol degradation. The RSM model shows a significant correlation between predicted and experimental values of photocatalytic degradation of phenol. The model’s accuracy was tested for 50 ppm of phenol under optimal conditions involving a catalyst concentration of 0.4 g/L catalysts and a solution pH of 6.5. The model predicted a degradation efficiency of 88.62%, whereas the experimentally achieved efficiency was 83.75%.

Synthesis of Highly Active Doped Graphitic Carbon Nitride using Acid‐Functionalized Precursors for Efficient Adsorption and Photodegradation of Endocrine‐Disrupting Compounds

“…The FTIR spectra of the doped and undoped g‐C 3 N 4 samples are presented in Figure 1b. The peaks observed between 1650 and 1242 cm −1 can be attributed to the stretching vibration modes of the C−N bond and the aromatic C=N heterocyclic species in repeated units of tri‐s‐triazine [12,15] . Additionally, the sharp peak appearing at 813 cm −1 in the spectra of BCN, OBCN, and SBCN is due to the breathing mode of the s‐triazine ring system.…”

“…Moreover, a minor peak due to the (100) plane is ascribed to repeated units of tri-s-triazine. [11][12] The PXRD peak intensities of BCN and OBCN are almost the same, while in the case of SBCN, the peak intensity is slightly lower. Although no peaks due to phosphorus were observed in PBCN, the intensity of the g-C 3 N 4 PXRD characteristic peaks has decreased, indicating the reduction in the crystallinity of this material.…”

“…g‐C 3 N 4 was prepared using the published procedure involving the thermal decomposition of melamine [12] . Specifically, a muffle furnace kept under a static air atmosphere was used to synthesize g‐C 3 N 4 from melamine (5 g) in a closed crucible.…”

“…The peaks observed between 1650 and 1242 cm À 1 can be attributed to the stretching vibration modes of the CÀ N bond and the aromatic C=N heterocyclic species in repeated units of tri-striazine. [12,15] Additionally, the sharp peak appearing at 813 cm À 1 in the spectra of BCN, OBCN, and SBCN is due to the breathing mode of the s-triazine ring system. Still, this peak was almost absent in the FTIR spectrum of PBCN, which indicates that tri-striazine in this catalyst undergoes a drastic modification.…”

Identification of Active Species in Photodegradation of Aqueous Imidacloprid over g-C3N4/TiO2 Nanocomposites

“…The solution was collected every 30 min to 150 min using a syringe with a microspore filter (0.45 µm). The concentration of IMI was analyzed by UV-Vis spectrophotometry at 268 nm, and the removal efficiency was calculated via Equation (4) [69].…”