In this research, the synthesis of biochar from cow dung and sewage sludge and its application for the removal of organic contaminants using methylene blue (MB) as the model molecule was evaluated. Experiments were performed using different concentrations of adsorbent and MB and were optimized by a response surface methodology (RSM). Dynamic models were adjusted to the experimental data and the regeneration of the bed was studied. The results showed that the optimal conditions to favor the adsorption of MB, in a fixed bed and making a comparison between the two biochar sources, were those where an adsorbent biochar concentration of 5 g and initial MB concentration of 10 mg L⁻¹ were used. The biochar prepared from cow dung presented the best adsorption conditions. Under these conditions, the breaking time was 172.73 min. The models of Thomas, Bohart–Adams, and Yoon–Nelson were applied for the study in fixed-bed columns and it was observed that the models were adjusted satisfactorily. Regeneration was possible for three different cycles, slightly diminishing the performance of the bed with elution of HNO₃. These results indicate that MB bed fixed adsorption on cow dung biochar is viable and suitable for water treatment.

中文翻译：

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牛粪与污水污泥制备生物炭的比较研究及其作为吸附剂去除水中有机污染物的应用

在这项研究中，评估了从牛粪和污水污泥中合成生物炭及其在使用亚甲蓝 (MB) 作为模型分子去除有机污染物中的应用。使用不同浓度的吸附剂和 MB 进行实验，并通过响应面方法 (RSM) 进行优化。根据实验数据调整动态模型并研究床层的再生。结果表明，在固定床中对两种生物炭来源进行比较，有利于 MB 吸附的最佳条件是吸附剂生物炭浓度为 5 g 和初始 MB 浓度为 10 mg L ^-1被使用。以牛粪为原料制备的生物炭具有最佳的吸附条件。在这些条件下，断裂时间为 172.73 分钟。Thomas、Bohart-Adams 和 Yoon-Nelson 的模型应用于固定床柱的研究，观察到模型调整得令人满意。对于三个不同的循环，再生是可能的，稍微降低了床的性能，洗脱 HNO ₃。这些结果表明，牛粪生物炭上的 MB 床固定吸附是可行的，适用于水处理。