Electro-Fenton (EF) process is a significant water treatment method for the degradation of dissolved organic matter (DOM) in water and has been widely studied and applied in the past decade to degrade various dissolved organics. During water treatment, in order to monitor the degradation efficiency, it is in dire need to develop rapid and accurate methods that are favorable to assay on-line and on-site to provide feedback in a timely manner. UV–Visible absorption spectroscopy and Excitation-Emission Matrix (EEM) fluorescence spectroscopy techniques are most potential to realize on-line DOM measurement, but the measurement accuracy is unsatisfactory because of the obligatory involvement of iron-containing interferents. This study aims to simplify the measurement system complexity while overcoming the effect of iron-containing interferents during the measurement. An intrinsic relationship between the measured DOM concentration and the ultraviolet absorption at ${\mathrm{\lambda }}_1$ and the light intensities of the fluorescence emission at ${\mathrm{\lambda }}_2$ is derived theoretically and proved, based on which the influence of iron ions and their complexes on the spectrum can be eliminated, thus the content of DOM in the Electro-Fenton process is accurately determined. The proposed dual wavelength analysis with combination of fluorescence emission and ultraviolet absorption spectroscopy can achieve high precision ($R^2=0.9882$, $RMSE=0.0131mg/L$). Furthermore, the on-line measurement design, called ultraviolet absorption-fluorescence emission dual wavelength analyzer, only includes one ultraviolet LED and two photodetectors. Its structure is simple and suitable for on-line monitoring DOM in EF process.

电芬顿 (EF) 工艺是一种重要的水处理方法，用于降解水中的溶解有机物 (DOM)，在过去十年中被广泛研究和应用以降解各种溶解有机物。在水处理过程中，为了监测降解效率，迫切需要开发快速、准确的方法，有利于在线和现场检测，及时提供反馈。紫外可见吸收光谱和激发发射矩阵 (EEM) 荧光光谱技术最有可能实现在线 DOM 测量，但由于含铁干扰物的强制性参与，测量精度并不令人满意。本研究旨在简化测量系统的复杂性，同时克服测量过程中含铁干扰物的影响。测得的 DOM 浓度与紫外线吸收之间的内在关系${\mathrm{\lambda }}_1$ 和荧光发射的光强度 ${\mathrm{\lambda }}_2$理论推导和证明，在此基础上可以消除铁离子及其配合物对光谱的影响，从而准确测定电芬顿过程中DOM的含量。所提出的结合荧光发射和紫外吸收光谱的双波长分析可以实现高精度（${\mathrm{电阻}}^2=0.9882$, $\mathrm{电阻}米秒乙=0.0131米G/升$）。此外，在线测量设计，称为紫外吸收-荧光发射双波长分析仪，仅包括一个紫外LED和两个光电探测器。其结构简单，适用于EF过程中在线监控DOM。