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The perchloroethylene (PCE, tetrachloroethylene), as a representative of chlorinated ethylenes and volatile organic compounds (VOCs), can be easily transported and remain in the atmosphere due to its volatility and stability properties. As a result, there is a crucial need to reduce this pollution to the extent permitted by international standards. The concentration of PCE determined with Gas chromatography–mass spectrometry analyzer (GC-MS). Activated nanocarbons (ACs) doped with nitrogen functional groups were prepared using the walnut shell as a precursor to evaluate their adsorption capacity for PCE vapors. Several techniques, including scanning electron microscopy (SEM), N2 adsorption-desorption, and the Fourier transforms infrared spectrometry (FTIR), were applied to characterize the physical-chemical properties of the ACs. It is found that the PCE adsorption considerably increased on the nitrogen-doped ACs (KNCWS) due to their structural and surface charge properties. By conducting kinetic study, the pseudo-first-order model matched well with experimental data.

A coupled adsorption–desorption thermo-kinetic model is developed incorporating both adsorption and desorption reactions. A local pseudo-equilibrium condition at the interface of adsorbent and adsorbate bulk phases was used as isotherm equation which can even be applied for multi-pollutants scenarios. The developed model is then validated using collected experimental data of heavy metal ions (Pb, Cu, Cd, Zn, and Ni). Comparisons were made for a number of isotherm and kinetic models to examine the performance of the proposed model. The developed model revealed desirable accuracy and superiority over other models in predicting the adsorption behavior and can be used for other systems of concern. The model correlates the adsorption kinetic with an [Formula: see text] value of 0.9391 and desorption kinetic with an [Formula: see text] value of 0.9383. By application of the proposed model to any available adsorption datasets, the individual characteristics of adsorption and desorption can be determined.