Assessment of the natural zeolite adsorption capacity for the removal of triclosan from the aqueous medium

The environment has been affected by pollutants originated from production activities, impacting the quality of water. An emerging contaminant found in superficial waters and highly studied is the triclosan (TCS). It is used in personal care products, whose removal is not possible by means of conventional water treatments processes, causing serious problems. Hence, effective removal of this contaminant is required. The adsorption arises as an effective and inexpensive method, where the only main issue is to find low-cost absorbents to make feasible its application. Zeolites are abundant materials with advantageous properties and economically accessible. Therefore, the aim of this study was to use natural zeolites for TCS adsorption from the aqueous medium. Accordingly, the characterization of the adsorbent was carried out as well as the tests to determine the optimal operational parameters. In this sense, the kinetics that better adjusted to data was the pseudo-secondorder. The Langmuir isotherm showed the best fit with a maximum capacity of 82.25 mg & BULL;g-1 at 318 K. Thermodynamic parameters revealed a spontaneous and exothermic process. Regarding the reuse of the adsorbent, it maintained its operational conditions through the five cycles with no loss of efficiency reported. These results show the effectiveness of natural zeolites in the removal of TCS, using small mass of adsorbent which can be reused, being, therefore, an environmentally suitable alternative in water treatment.