# Electrodegradation of Selected Water Contaminants: Efficacy and Transformation Products
## 4 Conclusions  
The removal efficiency and kinetic analysis of the EO of Triton X-100 (t-OPPE) and DBP in different supporting electrolytes confirmed the effectiveness of BDD anodes for the treatment of wastewater contaminated with emerging organic pollutants. For DBP, the second-order kinetic model provided the best fit in all tested electrolytes (NaCl, Na\({}_{2}\)SO\({}_{4}\), and H\({}_{2}\)SO\({}_{4}\)) with the highest degradation rate and shortest half-life observed in sulphuric acid, most likely due to the formation of highly reactive persulphate radicals. Similarly, slower but considerable degradation was observed in Na\({}_{2}\)SO\({}_{4}\) media. From an environmental engineering perspective, Na\({}_{2}\)SO\({}_{4}\) offers a practical and scalable choice for EO applications, balancing slightly lower oxidative power with greater operational safety, stability, and sustainability. In NaCl, indirect oxidation via chlorine-based species contributed to the degradation process, although with slower kinetics and with higher energy consumption. These findings highlight the significant influence of the electrolyte type on degradation kinetics, energy efficiency, and dominant oxidative pathways. Transformation products were studied only in the sulphate media and several oxidation products were identified, but no evidence of progressive degradation was seen, e.g., ring-opening products. The reasons are shorter EO treatment time and possibly a lack of identification due to unsuitable analytical methods for the detection of more polar TPs. Triton X-100 degradation was studied only in sodium sulphate, based on the experience with BTA and DBP. Removal followed first-order kinetics indicating that the rate of degradation was directly proportional to the contaminant concentration. In contrast, the second-order model provided a poorer fit, suggesting that reactive intermediates did not play a dominant role in the Triton X-100 oxidation mechanism. Additionally, the degradation of the transformation product, t-OP, also conformed to a first-order model, confirming the consistency of kinetic behaviour within this non-ionic surfactant family. The monitoring of the transformation products revealed some oxidative intermediates in the reaction pathway of Triton X-100 transformation to t-OP, while the latter further degraded and some ring-opening TPs were detected, such as simple dicarboxylic acids. For BTA, oxidated and chlorinated TPs were identified in sulphate and chloride media, respectively. The duration of electrooxidation (120 min for DBP and t-OPPE, or 150 min for BTA) did not allow for any significant mineralization as evidenced by the detectable concentrations of complex TPs still present at the end of experiments. Thus, the mineralization of the contaminants was very low or negligible and prolonged treatment should be applied to achieve it. Nevertheless, these results collectively demonstrate that BDD-based electrochemical oxidation is a robust and versatile method for the efficient removal of structurally diverse organic contaminants, making it a promising candidate for advanced water treatment technologies aimed at emerging pollutant control. The following supporting information can be downloaded at [[https://www.mdpi.com/article/10.3390/app15158434/s1](https://www.mdpi.com/article/10.3390/app15158434/s1)]([https://www.mdpi.com/article/10.3390/app15158434/s1](https://www.mdpi.com/article/10.3390/app15158434/s1)): S1--Literature review of research for emerging contaminants removal by electrodeposition. Table S1a. Literature review of research on dibuty1 phthalate removal by electrodeposition. Table S1b. Literature review of research on 1\(H\)-benzotriazole removal by electrodeposition. Table S1c. Literature review of research on Triton X-100 (t-OPPE) removal by electrodeposition. S2. Kinetics. Figure S2a. Comparison of experimental data with first- and second-order kinetic models for t-OP degradation. Figure S2b.