Performance investigation of Zeolitic Imidazolate Framework – 8 (ZIF-8) in the removal of trichloroethylene from aqueous solutions

Abstract

The presence of trichloroethylene in the groundwater has caused major concerns on a global scale. In this study, the effect of different parameters such as contact time (15–120 min), pH (3–12), adsorbent dose (0.05–0.35 g/L), and the initial concentration of TCE (5–50 μg/L) was studied. The structure of the adsorbent was determined by XRD, SEM, FT-IR, BET, and TEM. In this study, Freundlich and Langmuir isotherm models were used to calculate the equilibrium constants. Residual Trichloroethylene was measured using the GC-Mass. The removal rate of trichloroethylene increased with increasing contact time and adsorbent dosage while it decreased after an increase in pH and initial concentration of trichloroethylene. The best pH and adsorbent dose for the removal of trichloroethylene was 7.5 and 0.313 g/L, respectively. The optimum removal efficiency for TCE removal by ZIF-8 adsorbent was 96.29%. Kinetic studies showed that adsorption of TCE by ZIF-8 follows a pseudo second order. Langmuir isotherm with an R2 of 0.9926 for TCE was the best graph for the experimental data. The maximum adsorption capacity was 136.33 mg/g. The results showed that ZIF-8 adsorbent could be effective in removal of trichloroethylene from aqueous solution.