In this study, Ailanthus altissima sawdust was chemically activated and characterized by Scanning Electron Microscopy (SEM), Fourier Transform Infrared (FTIR), Energy Dispersive X rays (EDX), and surface area analyzer. The sawdust was used as an adsorbent for the removal of azo dye; Acid Yellow 29 (AY 29) from wastewater. Different kinetic and equilibrium models were used to calculate the adsorption parameters. Among the applied models, the more suitable model was Freundlich with maximum adsorption capacities of 9.464, 12.798, and 11.46 mg/g at 20 °C, 30 °C, and 40 °C respectively while R² values close to 1. Moreover, the kinetic data was best fitted in pseudo second order kinetic model with high R² values approaching to 1. Furthermore, adsorption thermodynamics parameters such as free energy, enthalpy, and entropy were calculated and the adsorption process was found to be exothermic with a value of ∆H° = −9.981 KJ mol⁻¹, spontaneous that was concluded from ΔG° values which were negative (−0.275, −3.422, and −6.171 KJ mol⁻¹ at 20, 30, and 40 °C respectively). A positive entropy change ∆S° with a value of 0.0363 KJ mol⁻¹ indicated the increase disorder during adsorption process. It was concluded that the activated sawdust could be used as a suitable adsorbent for the removal of waste material, especially dyes from polluted waters.

中文翻译：

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活性臭椿木屑作为吸附剂去除废水中酸性黄 29：动力学方法

在这项研究中，臭椿木屑被化学活化，并通过扫描电子显微镜 (SEM)、傅里叶变换红外 (FTIR)、能量色散 X 射线 (EDX) 和表面积分析仪进行表征。锯末用作吸附剂去除偶氮染料；来自废水的酸性黄 29 (AY 29)。使用不同的动力学和平衡模型来计算吸附参数。在应用模型中，更合适的模型是 Freundlich，在 20 °C、30 °C 和 40 °C 下的最大吸附容量分别为 9.464、12.798 和 11.46 mg/g，而 R ²值接近于 1。此外，动力学数据最适合具有高 R ^{2 的}伪二级动力学模型值接近 1。 此外，计算了吸附热力学参数，如自由能、焓和熵，发现吸附过程是放热的，ΔH° = -9.981 KJ mol ^-1，自发的得出结论ΔG° 值为负（分别在 20、30 和 40 °C 下为-0.275、-3.422 和 -6.171 KJ mol ^-1）。值为 0.0363 KJ mol ^-1的正熵变化 ∆S°表明吸附过程中的增加无序。得出的结论是，活化的锯末可用作合适的吸附剂，用于去除废水中的废料，尤其是染料。