Removal of Trichloroethylene by Clay Modified with Cationic Surfactant in Aqueous Solutions: Equilibrium,Kinetic, and Thermodynamic Study

Trichloroethylene (TCE) is commonly found in ground water, and it may serve as a major source of many types of cancers such as kidney, liver, lymphatic glands, and spinal cord. In the present research, TCE uptake from aqueous media by montmorillonite (Mt) modified by tetradecyl trimethyl ammonium bromide (TTAB) surfactant was explored. Firstly, the characteristics of raw and modified montmorillonite (raw-Mt and TTAB-Mt) were analyzed by SEM, FTIR, XRD, and XRF instruments. Then, the sorption process was evaluated as a function of different factors such as surfactant loading rate, pH, ionic strength, contact time, sorbent dosage, TCE concentration, temperature, and regeneration agent. The maximum TCE sorption by the modified clay was obtained at surfactant loading rate of 120% cation exchange capacity of the clay. The maximum removal efficiency of TCE by the modified clay was 99.6% at pH 5 and 30 min contact time. The findings also exhibited that the isotherm and kinetic sorption followed the Freundlich and pseudo-second-order models, respectively. It can be concluded that TTAB-Mt, as a cheap, abundant, non-toxic, and environmental friendly adsorbent can be considered to remove TCE in aqueous phase.