Abstract: In response to the growing need for effective organic dye treatment, this study constructed a supported titanium dioxide (TiO2) photocatalytic degradation system utilizing a spinning disc reactor (SDR). High-quality anatase TiO2 films exhibiting superior catalytic activity were optimized and fabricated onto the disc surface via advanced magnetron sputtering technology. The research systematically investigated the influence of critical operational parameters—specifically disc rotational speed, feed flow rate, initial methylene blue (MB) concentration, and liquid feeding mode—on the degradation performance of MB as a model pollutant. Experimental results demonstrated that the reactor achieved optimal mass transfer and reaction efficiency at a rotational speed of 200 r/min and a feed flow rate of 2.0 L/min. It was observed that excessive rotational speeds (exceeding 200 r/min) had a detrimental effect, inhibiting the degradation reaction. This phenomenon was attributed to liquid film slippage and enhanced light scattering, which collectively reduced photon absorption efficiency. Furthermore, a detailed kinetic analysis revealed distinct response mechanisms for the volumetric reaction rate constant (kappv) and the surface reaction rate constant (kapps). Notably, kapps decreased significantly with the increase in Reynolds number ratio (α), a competitive effect between the inlet scouring effect and disk shear. The substrate renewal induced by inlet scouring effect dominated the mass transfer enhancement. Conversely, kappv was found to be constrained by the dilution effect caused by the increased volume of the liquid film. Based on dimensionless analysis, a robust predictive correlation for the surface reaction rate constant was developed, incorporating both Rein and the rotational Reynolds number (Reω). The model demonstrated high accuracy, with a predictive deviation strictly controlled within ±16%. Ultimately, this study elucidates the complex structure-activity relationships involving liquid film thickness, residence time, wall shear rate, Reynolds number ratio, and photocatalytic efficiency within the SDR. These comprehensive findings provide important theoretical foundations and essential engineering parameters for the intensification of photocatalytic processes in environmental applications.

Key words: spinning disc reactor, photocatalysis, methylene blue degradation, reaction kinetics

摘要： 本研究针对有机染料处理，构建了基于转盘反应器(SDR)的负载型TiO2光催化降解体系。利用磁控溅射技术制备了具有高催化活性的锐钛矿型TiO2薄膜，并系统探究了转盘转速、流量、初始亚甲基蓝(MB)浓度及进液方式对MB降解性能的影响规律。实验结果表明，在转速为200 r/min、流量为2.0 L/min时，反应器达到最佳传质与反应效率；过高的转速(>200 r/min)会导致液膜滑移和光散射增强，从而抑制降解反应。动力学分析揭示了体积反应速率常数(kappv)与表面反应速率常数(kapps)的差异化响应机制：kapps随雷诺数比α升高显著降低，表明进口冲刷效应与转盘剪切存在竞争效应，进口冲刷引发的底物界面更新在传质强化中占据主导；而kappv则受液膜体积增大的稀释效应制约。基于无量纲分析，建立了包含Rein和周向雷诺数(Reω)的表面反应速率常数预测关联式，预测偏差控制在±16%以内。本研究阐明了SDR中液膜厚度、停留时间、壁面剪切率、雷诺数比与光催化效率的构效关系，为强化光催化过程提供了理论依据和工程参数。

关键词: 转盘反应器, 光催化, 亚甲基蓝降解, 反应动力学