Sulfamethazine degradation by heterogeneous photocatalysis with ZnO immobilized on a glass plate using the heat attachment method and its impact on the biodegradability

Abstract

In this paper, the degradation of sulfamethazine (SMT) was performed using of photocatalytic process in the presence of ZnO catalyst immobilized on glass plate (on ZnO/glass plate) under UV light. The ZnO/glass plate was characterized by X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectra; the results of the characterization demonstrated that the properties of ZnO/glass plate were maintained unmodified. The adsorption and the photolysis tests revealed the absence of adsorption of SMT onto ZnO/glass plate and the absence of direct photolysis of SMT. The effect of the initial solution pH, the flow rate and the initial concentration of SMT on the photocatalytic process was studied and optimized by using central composite design (CCD). The model equation obtained led to a classification of these parameters based on their level of significance. The results suggested that the most influential factor was the initial concentration of SMT (x 2 ), which had the strongest effect on the response (-11.6) and the negative sign of the coefficient suggested that the degradation of SMT decreased for increasing initial SMT concentration. It was followed by the flow rate with positive effect on the yield of SMT degradation (+2.06). The model also demonstrated the absence of pH effect in the studied interval and that the strongest interaction was between the pH and the flow rate. The kinetic of degradation of the SMT can be described by a pseudo A c c e p t e d M a n u s c r i p t 2first order kinetic model for 10 and 50 mg/L of SMT; while the kinetic of degradation was described by a pseudo-second-order kinetic model for the highest initial amount, [SMT] 0 =100 mg/L. The optimal values of the solution pH, the flow rate and the initial concentration of SMT were 6, 0.56 L/min and 11 mg/L respectively. Under these conditions the removal efficiency of SMT was 96 % and the BOD 5 /COD ratio increased from 0 to 0.20 after 5h of irradiation time.

Photocatalytic Degradation of Tartrazine and Naphthol Blue Black Binary Mixture with the TiO2 Nanosphere under Visible Light: Box-Behnken Experimental Design Optimization and Salt Effect

“…As shown in Figure 6b, the R 2 (correlation coefficient) values obtained for TTZ concentrations of 2, 5, 8, and 12 ppm were 0.973, 0.976, 0.999, and 0.972, respectively, demonstrating that the pseudo-first-order kinetic model describes the degradation of TTZ by TiO 2 -NS. We also note that k increases inversely with contaminant concentration, as has already been documented in previous studies [54]. For the initial TTZ concentration of 2 ppm, the degradation efficiency reaches 100% after 60 min of visible light irradiation, and then there are no kinetics for modeling after this time.…”

Synthesis and Application of a Fe3O4/Ag3PO4/g-C3N4 Magnetic Composite Photocatalyst for Sulfonamide Antibiotics Degradation

“…Conversely, the introduction of BQ and EDTA-2Na led to a significant decrease in the degradation rate. This data implies that •O 2 − and h + are the primary active species responsible for the degradation of SMZ in the presence of the Fe 3 O 4 /Ag 3 PO 4 /g-C 3 N 4 photocatalyst and under visible light conditions [61]. Drawing from these observations, we propose a detailed mechanism for the photocatalytic degradation of SMZ by the Fe 3 O 4 /Ag 3 PO 4 /g-C 3 N 4 photocatalyst under visible light.…”

The photocatalytic degradation of a binary textile dyes mixture within a new configuration of loop reactor using ZnO thin film-phytotoxicity control

“…The glass plate was selected as substrate for ZnO immobilization in this study. The preference of this support goes to its inertness coupled with its ability to withstand high calcination temperatures, its availability, chemical stability, nontoxicity and low cost [28,29].…”