This work investigates the online monitoring of fluoride ion concentration in proton exchange membrane water electrolysers (PEMWE) effluent water using an automated ion chromatography (IC) setup. Prototype catalyst coated membranes (CCMs) with different thicknesses have been tested and fluoride measurements under different operating conditions at both single cell and stack level have been carried out. The study reports the impact of both current density and temperature on the cathodic fluoride concentrations showing a maximum at low current densities, at around 0.4 A/cm² for the single cells, and at 0.2–0.4 A/cm² for the short stack. It is also reported that higher PEMWE working temperature has an adverse effect on the membrane stability, resulting in a significant increase of the fluoride release at the cathode outlet. Noticeably, CCMs with reduced membrane thickness exhibited lower values of area-specific fluoride release rates with respect to thicker CCMs. Finally, the study also reports that fluoride concentrations and water conductivity are very well correlated, displaying a linear correlation. This new finding could represent a low cost and straightforward method to obtain quantitative information about membrane degradation rates in larger commercial PEMWE systems.

这项工作调查了使用自动离子色谱（IC）装置在线监测质子交换膜水电解槽（PEMWE）废水中氟离子浓度的情况。已经测试了具有不同厚度的原型催化剂涂覆的膜（CCM），并且已经在单电池和堆叠水平下在不同操作条件下进行了氟化物测量。该研究报告了电流密度和温度对阴极氟化物浓度的影响，在低电流密度下显示最大，单个电池约为0.4 A / cm ²，而在0.2–0.4 A / cm ^2时对于短筹码。还据报道，较高的PEMWE工作温度对膜稳定性有不利影响，导致阴极出口处氟化物释放的显着增加。值得注意的是，与较厚的CCM相比，膜厚度减小的CCM的单位面积氟化物释放速率值较低。最后，该研究还报告说，氟化物浓度与水的电导率具有很好的相关性，呈线性关系。这一新发现可能代表一种低成本，简单的方法，可用于获得有关大型商用PEMWE系统中膜降解速率的定量信息。