In this work, fly ash from a Brazilian thermal power plant was employed as a low-cost raw catalyst for Procion red degradation by photo-Fenton process. The ash was characterized by X-ray fluorescence (XRF), X-ray diffraction (XRD), nitrogen adsorption/desorption isotherms (BET), Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) coupled with energy-dispersive X-ray spectrometry (EDX). The material had an iron content of 4.10 wt%, distributed homogeneously on the solid surface. The ash particles showed mainly spherical morphology between 0.5 and 20 µm. The catalyst presented promising activity, reaching 93% of dye decolorization at 60 min of reaction, and 85% of organic load removal at 240 min. The predominant oxidizing species involved on the degradation of dye molecules during the photo-Fenton reaction were the hydroxyl radicals (HO · ). The material showed remarkable stability and reusability after five successive cycles of reuse. The reaction intermediates were identified by LC/MS analysis and a reaction pathway was proposed. Reaction pathway for degradation of an emerging contaminant by photo-Fenton Fly ash was a promising catalyst for the degradation of Procion red The catalytic efficiency was 93.6% decolorization and 85% TOC removal Fly ash presented good stability and low level of deactivation after five uses

中文翻译：

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以粉煤灰为低成本原料催化剂光芬顿氧化降解水中新出现污染物的反应途径研究

在这项工作中，来自巴西热电厂的飞灰被用作通过光芬顿法降解普罗西翁红的低成本原料催化剂。灰分通过 X 射线荧光 (XRF)、X 射线衍射 (XRD)、氮吸附/解吸等温线 (BET)、傅里叶变换红外光谱 (FTIR) 和扫描电子显微镜 (SEM) 与能量色散X 射线光谱法 (EDX)。该材料的铁含量为 4.10 重量％，均匀分布在固体表面上。灰分颗粒主要表现在 0.5 到 20 µm 之间的球形形态。该催化剂表现出良好的活性，在反应 60 分钟时达到 93% 的染料脱色，在 240 分钟时去除 85% 的有机负载。在光芬顿反应过程中，参与染料分子降解的主要氧化物质是羟基自由基（H2O·）。该材料在连续五次重复使用后表现出显着的稳定性和可重复使用性。通过LC/MS分析鉴定反应中间体并提出反应途径。光芬顿粉煤灰降解新兴污染物的反应途径是降解 Procion red 的有前景的催化剂 催化效率为 93.6% 脱色和 85% TOC 去除 粉煤灰在使用五次后表现出良好的稳定性和低水平的失活