高铁-光催化氧化协同去除藻毒素的研究

Efficiency of Microcystin-LR Removal by Photocatalysis Combined with Ferrate Oxidation

研究了高铁 光催化氧化体系去除水中藻毒素的效能 .结果表明 ,通过投加 1 0mg/L的高铁到光催化体系中 ,由于高铁的强氧化性及其还原产物可作为电子捕获剂的特点 ,可将光催化效率从 6 3%提高到 1 0 0 % ,实现快速完全去除藻毒素的目的 .同时对照研究了高铁、光催化、Fe3 + 光催化、高铁 光催化 4种不同反应体系对藻毒素去除的效能 .结果显示 ,单纯的高铁或光催化都可以降解一部分藻毒素 ,但去除率低 ,分别为 5 4 %和 6 3% ,且需大剂量的高铁投加或大大延长光照时间 .而在Fe3 + 光催化、高铁 光催化体系中 ,只需投加 1 0mg/L的三价铁或高铁 ,就可以将藻毒素去除率提高到 73%和 1 0 0 % ,但采用高铁协同光催化体系比三价铁协同光催化体系更有效 .也就是说在本体系中 ,高铁具有十分重要的作用 ,明显存在着高铁与TiO2

This study focused on enhancing photocatalytic degradation of microcystin LR following the addition of ferrate to the process. The degradation efficiency of ferrate and the photocatalysis was 54% and 63% respectively. However, when ferric or ferrate was added to the photocatalytic process, a significant enhancement in the rate of the photocatalytic degradation was observed and the efficiency can be increased to 73% or 100%. The results demonstrate that relatively low ferrate doses (10 mg/L) are sufficient not only for pre degradating amount of toxin but also for supplying the Fe 3+ enhance the rates of photocatalytic process to destroy the toxin further. At the same time, it indicates the advantage of using ferrate with the photocatalytic system comparing with ferric.