Azo dyes are the most widely used dyes in the textile industry due to their stability, but their redundancy to degradation is of significant concern, particularly to aquatic ecosystems. In the present study, a lab-scale aerobic sequential batch reactor (SBR) was operated to analyze the degradation of mixed reactive azo dyes at a concentration of 100–1000 mg/L. The chemical oxygen demand (COD) removal increased from 34% to 61.15% and then dropped to 21.16% at the highest used concentration. The biochemical oxygen demand (BOD) removal decreased from 63% to 55.55% to 28.14% with an increasing dye concentration. The biosorption experiment and dried activated sludge (DAS) successfully removed about 0.300 mg of dyes by absorption within 2 hours. A toxicity assessment was carried out by employing a phytotoxicity test on Vigna radiata. The percentage of germination was used to detect the toxic effects of untreated dye-containing wastewater on plant growth. The treated wastewater showed 100% germination compared to 70% in untreated wastewater containing 100 mg/L mixed dyes, confirming the treatment’s efficacy.

中文翻译：

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好氧序批式反应器中混合偶氮染料的处理和使用辐射的毒性评估

偶氮染料因其稳定性而成为纺织工业中使用最广泛的染料，但它们对降解的冗余性是一个重要问题，尤其是对水生生态系统而言。在本研究中，运行实验室规模的好氧序批式反应器（SBR）来分析浓度为 100-1000 mg/L 的混合活性偶氮染料的降解。化学需氧量 (COD) 去除率从 34% 增加到 61.15%，然后在最高使用浓度下下降到 21.16%。随着染料浓度的增加，生化需氧量 (BOD) 去除率从 63% 下降到 55.55% 到 28.14%。生物吸附实验和干燥活性污泥 (DAS) 在 2 小时内成功吸附去除了约 0.300 mg 的染料。通过对植物毒性试验进行毒性评估豇豆辐射。发芽率用于检测未经处理的含染料废水对植物生长的毒性作用。处理后的废水显示出 100% 的发芽率，而含有 100 mg/L 混合染料的未处理废水中的发芽率为 70%，证实了处理的有效性。