This study investigates the degradation and mineralization of BTEX by heterogeneous electro-Fenton process using GO/MWCNT/Fe₃O₄ as a catalyst and MWCNT-Ce/WO₃/GF as an electrode. The nanoscale MWCNT-Ce/WO₃ composite catalyst was distributed more evenly on GF surface to form a catalyst layer with higher oxygen reduction reaction performance. After optimization of pH and time variables, the Box–Behnken experimental design (BBD) and response surface methodology (RSM) were used to design and optimize the performance of proposed system and energy consumption. Analysis of variance (ANOVA) revealed that the quadratic model was adequately fitted to the experimental data with R² (0.98) and adj-R² (0.97). The significance levels of linear and interaction effects of the reaction parameters on process efficiency were obtained. Then, the optimization of the working conditions for the design of a sustainable treatment system with optimum efficiency was carried out using a response surface methodology. The experiment carried out in the calculated optimal conditions for the electro-Fenton degradation process (current intensity 300 mA, catalyst dosage of 0.6 g, initial BTEX concentration of 100 ppm, and electrode distance of 1 cm) showed a BTEX removal of 73.2% and energy consumption of 12.3 (kWh/m³) close to the theoretical value predicted by the model 73. 2% and 11.8 (kWh/m³), respectively. Furthermore, the reusability test of GO/MWCNT/Fe₃O₄ nanocomposite after several cycles confirmed the high catalytic activities of adsorbent. Comparing the proposed system with conventional GF electrode and Fe²⁺ catalyst showed that modification of cathode and catalyst led to increasing COD removal efficiency by around 36.6 and 31.6%, respectively. The findings of present study revealed that the proposed heterogeneous electro-Fenton process can be utilized as pre-treatment technology to improve the biodegradability and reduce the organic load of wastewater by combine oxidation and coagulation.

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本研究以GO / MWCNT / Fe ₃ O ₄为催化剂，MWCNT-Ce / WO ₃ / GF为电极，通过非均相电Fenton工艺研究了BTEX的降解和矿化作用。纳米级MWCNT-Ce / WO ₃复合催化剂更均匀地分布在GF表面，形成了具有较高氧还原反应性能的催化剂层。在优化pH和时间变量之后，使用Box–Behnken实验设计（BBD）和响应面方法（RSM）来设计和优化所建议系统的性能和能耗。方差分析（ANOVA）表明，二次模型与R ²（0.98）和adj-R ²（0.97）。获得了反应参数对过程效率的线性和相互作用影响的显着性水平。然后，使用响应面方法对设计最佳效率的可持续处理系统的工作条件进行了优化。在计算得出的电芬顿降解过程的最佳条件下进行的实验（电流强度300 mA，催化剂用量为0.6 g，初始BTEX浓度为100 ppm，电极距离为1 cm）显示BTEX去除率为73.2％，能耗为12.3（kWh / m ³），接近模型73预测的理论值。分别为2％和11.8（kWh / m ³）。此外，GO / MWCNT / Fe ₃的可重复使用性测试几次循环后的O ₄纳米复合材料证实了吸附剂的高催化活性。将所建议的系统与常规GF电极和Fe ²⁺催化剂进行比较表明，阴极和催化剂的改性分别使COD去除效率提高了约36.6和31.6％。本研究的发现表明，所提出的非均相电芬顿法可以作为预处理技术，通过结合氧化和混凝来提高生物降解性并降低废水的有机负荷。

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