A process aimed at the recovery of terbium from liquid solutions using activated carbon (AC) derived from spent coffee grounds (SCG) was assessed. AC was obtained using the hydro-alcoholic treatment of SCG, followed by the physical activation of the as-obtained product. The AC exhibited both microporous and mesoporous structures, which were shown by the corresponding nitrogen adsorption–desorption isotherms and scanning electron microscopy (SEM) images. In addition, a certain graphitic character was found in the micro-Raman measurements. By use of this AC, terbium adsorption was investigated, and the influence of solution pH, temperature, and the adsorbent amount on terbium uptake was tested. In addition, adsorption isotherms and kinetic studies were also evaluated. The best fit was found for the type-1 Langmuir isotherm and pseudo-second-order kinetics model. Thermodynamic studies revealed that terbium adsorption is an endothermic and spontaneous process. Terbium desorption by the use of acidic solutions was also investigated. This work demonstrated that it is possible to recover this valuable metal from liquid solution using the present AC.

中文翻译：

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从废咖啡渣中获得的活性炭在液体溶液中有效Effective回收中的应用

评估了一种旨在使用衍生自废咖啡渣（SCG）的活性炭（AC）从液体溶液中回收ter的方法。使用SCG的水-醇处理获得AC，然后将所得产物进行物理活化。AC表现出微孔和中孔结构，分别由相应的氮吸附-解吸等温线和扫描电子显微镜（SEM）图像显示。另外，在微拉曼测量中发现了一定的石墨特性。通过使用这种AC，研究了adsorption的吸附，并测试了溶液的pH，温度和吸附量对on吸收的影响。此外，还评估了吸附等温线和动力学研究。对于1型Langmuir等温线和拟二级动力学模型，发现了最佳拟合。热力学研究表明，adsorption的吸附是一个吸热和自发过程。还研究了使用酸性溶液对de的解吸。这项工作表明，使用本发明的AC可以从液体溶液中回收这种有价值的金属。