The release control of organic dye pollutants has become a global issue, and improper disposal of red mud(RM) can also cause environmental pollution. In this paper, a novel composite material, RM-SC-HA, was prepared to adsorb MB (methylene blue) from dye wastewater by co-hydrothermal treatment using RM, sucrose, and humic acid as raw materials. RM-SC-HA is simple to prepare and has better adsorption of MB in dye wastewater. The results supported the proposed secondary (R2 = 0.99) kinetic model, which states that chemisorption is the primary form of adsorption. The maximum amount of adsorption, which was achieved by Langmuir's isothermal model, was 417.12 mg/g. In addition, the adsorption mechanism can be attributed to the role of electrostatic interactions, hydrogen bonding, π-π stacking and void diffusion. When RM-SC-HA was used to treat simulated industrial wastewater samples, the removal rate was also maintained at a high level(About 90 %). In addition, RM-SC-HA has good magnetic properties and reusability. Its magnetic properties (saturation magnetization value of 2.49 emu/g) make it easy to separate from water under an applied magnetic field. The present study provides an efficient novel MB adsorbent and promotes the practical application of modified RM composites in water purification.

中文翻译：

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腐植酸蔗糖改性赤泥对染料废水亚甲蓝的有效吸附性能及机理


有机染料污染物的释放控制已成为一个全球性问题，赤泥（RM）的不当处理也会造成环境污染。本文以 RM、蔗糖和腐植酸为原料，通过共水热处理制备了一种新型复合材料 RM-SC-HA，以染料废水中吸收 MB（亚甲蓝）。RM-SC-HA制备简单，对染料废水中的MB有更好的吸附。结果支持了所提出的二级 （R2 = 0.99） 动力学模型，该模型指出化学吸附是吸附的主要形式。通过 Langmuir 的等温模型实现的最大吸附量为 417.12 mg/g。此外，吸附机制可归因于静电相互作用、氢键、π-π 堆叠和空隙扩散的作用。当 RM-SC-HA 处理模拟工业废水样品时，去除率也保持在较高水平 （约 90 %）。此外，RM-SC-HA具有良好的磁性和可重复使用性。它的磁性（饱和磁化值为 2.49 emu/g）使其在外加磁场下很容易与水分离。本研究提供了一种高效的新型 MB 吸附剂，促进了改性 RM 复合材料在水净化中的实际应用。