Abstract Biodiesel effluent demands treatment to enhance their organoleptic properties and to reduce the levels of organic load and toxicity. A step of coagulation-flocculation using 0.50 mmol L−1 Fe(NO3)3 was applied at the natural pH of the effluent (pH 2.9) removing its turbidity and apparent color. A solar/photo-Fenton process was employed to minimize the chemical oxygen demand – COD, when multiple additions of oxalate were done at intervals of 50 kJ m−2 of accumulated UVA radiation, during the photocatalytic reaction. The best results were achieved using 1.0 mmol L−1 of ferrioxalate, allowing reducing in 72% the COD and in 76% the biochemical oxygen demand of the treated effluent, after 602 kJ m−2 of accumulated dose of UVA radiation. Concomitantly, the acute toxicity to Vibrio fischeri was reduced from 70% to 6%. In view of this, this modality of treatment can be a good alternative for decontamination and detoxification of this kind of wastewater, mainly considering that no further step of neutralization is need once that during the treatment the pH increase up to close 7, and that solar energy can be employed, reducing costs related to energy consumption.

中文翻译：

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在基于使用太阳辐射的光芬顿工艺中使用草酸铁强化生物柴油废水处理

摘要 生物柴油流出物需要进行处理以增强其感官特性并降低有机负荷和毒性水平。在流出物的自然 pH 值 (pH 2.9) 下，使用 0.50 mmol L-1 Fe(NO3)3 进行混凝-絮凝步骤，以去除其浊度和表观颜色。当在光催化反应期间以 50 kJ m-2 累积 UVA 辐射的间隔多次添加草酸盐时，采用太阳能/光芬顿工艺来最小化化学需氧量 - COD。使用 1.0 mmol L-1 的草酸铁获得最佳结果，在累积 602 kJ m-2 的 UVA 辐射剂量后，可将处理后的废水的 COD 降低 72%，生化需氧量降低 76%。同时，对费氏弧菌的急性毒性从 70% 降低到 6%。鉴于此，