Data underlying the publication: Photocatalytic ceramic membrane: Effect of the illumination intensity and distribution

The principles and application of heterogeneous photocatalytic processes have gained wide attention, especially to the effectiveness of the process. In this work, a mono and a multi-LED lamp are used to study the impact of the UV light intensity and distribution on the semiconductor surface during the degradation of organic compounds in water. A well-defined scan of the electromagnetic radiation profile on the surface of the membrane was obtained and evaluated. Comparing two lamp configurations with a total photon flux of 210 W.m^-2 and using a filtration rate of 9.7 L.m^-2.h^-1, resulted in 20 % more degradation for the most homogeneous light distribution. Furthermore, the reaction rate relation to the photon flux was also studied, with a surface reaction model that includes possible mass transfer limitations. The surface reaction constant increased linearly with the irradiation intensity for the complete studied range [50 to 550 W.m^-2] for the most homogeneous illumination distribution. A less uniform distribution resulted in a less than proportional reaction rate constant with respect to the incident photon flux between 100 and 210 W.m^-2. This work adds valuable information to the photocatalysis field to improve the light efficiency in a photoreactor to enhance the degradation of pollutants.

非均相光催化过程（heterogeneous photocatalytic processes）的原理与应用已得到广泛关注，其中该过程的催化效能尤为受到重视。本研究采用单LED灯（Light Emitting Diode，LED）与多LED灯两种光源，探究水体有机污染物降解过程中，紫外光（Ultraviolet，UV）强度及其分布对半导体表面的影响。本研究获取并表征了膜表面电磁辐射分布轮廓的精准扫描结果。在总光子通量（photon flux）设定为210 W·m⁻²、过滤速率为9.7 L·m⁻²·h⁻¹的条件下对比两种灯组配置，结果表明光分布最均匀的配置可使污染物降解率提升20%。此外，本研究还探究了反应速率与光子通量的关联关系，并构建了考虑传质限制的表面反应动力学模型。对于光分布最均匀的工况，在50~550 W·m⁻²的全部研究辐照强度范围内，表面反应速率常数均随辐照强度呈线性增长。而在100~210 W·m⁻²的区间内，光分布均匀性较差的工况下，反应速率常数的增长幅度低于入射光子通量的提升幅度。本研究为光催化领域提供了宝贵的参考数据，有助于优化光反应器（photoreactor）的光利用效率，进而强化污染物降解效果。