Lu Tongbin, Zhao Hui, Jian Liang, Ji Rong, Pan Chengsi, Wang Guangli, Dong Yuming, Zhu Yongfa
International Joint Research Center for Photo-responsive Molecules and Materials, School of Chemical and Material Engineering, Jiangnan University, Wuxi, 214122, China.
International Joint Research Center for Photo-responsive Molecules and Materials, School of Chemical and Material Engineering, Jiangnan University, Wuxi, 214122, China.
Environ Res. 2023 Apr 1;222:115361. doi: 10.1016/j.envres.2023.115361. Epub 2023 Jan 28.
The Fenton process is a widely used to remedy organic wastewaters, but it has problems of adding HO, low utilization efficiency of HO and low mineralization efficiency. Here, a new photocatalysis-self-Fenton process was exploited for the removal of persistent 4-chlorophenol (4-CP) pollutant through coupling the photocatalysis of 4-carboxyphenylboronic acid edge covalently modified g-CN (CPBA-CN) with Fenton. In this process, HO was in situ generated via photocatalysis over CPBA-CN, the photogenerated electrons assisted the accelerated regeneration of Fe to improve the utilization efficiency of HO, and the photogenerated holes facilitated the enhancement of 4-CP mineralization. Under the conjugation of CPBA, the electronic structure of CN was optimized and the molecular dipole was enhanced, resulting in the deepening valence band position, accelerated electron-hole pair separation, and improved O adsorption-activation. Therefore, the incremental 4-CP degradation rate in the CPBA-CN photocatalysis-self-Fenton process was approaching 0.099 min, by a factor of 3.1 times compared with photocatalysis. The parallel mineralization efficiency increased to 74.6% that was 2.1 and 2.6 times than photocatalysis and Fenton, respectively. In addition, this system maintained an excellent stability in the recycle experiment and can be potentially applied in a wide range of pHs and under the coexistence of various ions. This study would provide new insights for improving Fenton process and promote further development of Fenton in organic wastewater purification.
芬顿法被广泛用于处理有机废水，但其存在添加羟基自由基（HO·）的问题，HO·的利用效率低且矿化效率低。在此，通过将4-羧基苯硼酸边缘共价修饰的石墨相氮化碳（CPBA-CN）的光催化与芬顿反应耦合，开发了一种新的光催化-自芬顿法来去除持久性4-氯苯酚（4-CP）污染物。在该过程中，HO·通过CPBA-CN上的光催化原位生成，光生电子辅助加速铁的再生以提高HO·的利用效率，光生空穴促进4-CP矿化的增强。在CPBA的共轭作用下，CN的电子结构得到优化，分子偶极增强，导致价带位置加深，电子-空穴对分离加速，氧吸附-活化改善。因此，CPBA-CN光催化-自芬顿过程中4-CP降解速率的增量接近0.099 min⁻¹，与光催化相比提高了3.1倍。平行矿化效率提高到74.6%，分别是光催化和芬顿法的2.1倍和2.6倍。此外，该系统在循环实验中保持了优异的稳定性，并且在广泛的pH值和各种离子共存的情况下都具有潜在的应用价值。本研究将为改进芬顿法提供新的见解，并促进芬顿法在有机废水净化中的进一步发展。
