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 (x₂), 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-first 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 concentration, [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. Under these conditions the removal efficiency of SMT was 96% and the BOD₅/COD ratio increased from 0 to 0.20 after 5 h of irradiation time.

在本文中，在光固定在玻璃板上（ZnO /玻璃板上）的ZnO催化剂存在下，在紫外光下，采用光催化工艺进行了磺胺二甲嗪（SMT）的降解。ZnO /玻璃板通过X射线衍射（XRD）和傅里叶变换红外（FTIR）光谱进行表征。表征结果表明，ZnO /玻璃板的性能保持不变。吸附和光解试验表明，不存在SMT在ZnO /玻璃板上的吸附，也不存在SMT的直接光解。研究了初始溶液的pH值，流速和表面活性剂的初始浓度对光催化过程的影响，并采用中心复合设计（CCD）进行了优化。获得的模型方程式根据这些参数的显着性等级对这些参数进行了分类。结果表明，影响最大的因素是SMT的初始浓度（x₂）对响应的影响最大（-11.6），系数的负号表明SMT的降解随初始SMT浓度的增加而降低。紧随其后的是流速，对SMT降解的收率产生积极影响（+ 2.06）。该模型还证明了在研究的时间间隔内没有pH效应，并且最强的相互作用是在pH和流速之间。SMT降解的动力学可以通过10和50 mg / L SMT的拟一级动力学模型来描述。而降解的动力学用最高初始浓度[SMT] ₀的拟二级动力学模型描述。 = 100毫克/升。溶液pH，流速和SMT初始浓度的最佳值为6、0.56 L / min和11 mg / L。在这些条件下，SMT的去除效率为96％，BOD ₅ / COD比在照射5小时后从0增加到0.20。