A new modified walnut shell (TWNS) was synthesized through sequentially reacting the walnut shell (WNS) with thionyl chloride and triethylamine, and it was applied to adsorb Reactive Brilliant Blue (RB-19) from dye wastewater. In the range of 288 to 308 K, the isotherms, thermodynamics, and kinetics of RB-19 adsorption onto TWNS were investigated. The isothermal experimental data have a good correlation with the Langmuir isotherm model, and the theoretical maximum monolayer adsorption capacity of TWNS was 258.59 mg/g at 288 K. The kinetic data of RB-19 adsorption onto TWNS accorded with the pseudo-second-order model. The diffusion mechanism of RB-19 adsorption onto TWNS was studied by Weber and Morris intraparticle diffusion equation and Boyd and Reichenberg model, and the results showed the adsorption is primarily controlled by membrane diffusion. The thermodynamic calculation results demonstrated that the adsorption process of RB-19 onto TWNS is a spontaneous, exothermic, and favorable process. Moreover, the recycled TWNS retains high adsorption capacity after four cycles.

中文翻译：

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使用改性核桃壳从水溶液中吸附活性亮蓝染料：动力学、平衡和热力学

通过将核桃壳（WNS）与亚硫酰氯和三乙胺依次反应合成了一种新型改性核桃壳（TWNS），并将其应用于染料废水中活性艳蓝（RB-19）的吸附。在 288 到 308 K 的范围内，研究了 RB-19 吸附到 TWNS 上的等温线、热力学和动力学。等温实验数据与Langmuir等温线模型具有良好的相关性，TWNS在288 K时的理论最大单层吸附容量为258.59 mg/g。RB-19吸附在TWNS上的动力学数据符合准二级模型。利用Weber和Morris粒子内扩散方程以及Boyd和Reichenberg模型研究了RB-19吸附在TWNS上的扩散机理，结果表明吸附主要受膜扩散控制。热力学计算结果表明RB-19在TWNS上的吸附过程是一个自发、放热、有利的过程。此外，回收的 TWNS 在四次循环后仍保持高吸附能力。