Triclosan Transformation On Montmorillonite Surface.

Triclosan (TCS) is widely used antibacterial compound in consumer products and frequently detected in wastewater treatment plants. If not degraded during wastewater treatment processes, there is a potential for this compound to get into the environment via wastewater effluent and biosolids, resulting in adverse effect on the environment. The objective of this study was to investigate TCS transformation on surfaces of montmorillonite and Fe(III)-saturated montmorillonite. TCS was incubated with montmorillonite and Fe(III)-saturated montmorillonite respectively at two different concentrations for up to 100 days at room temperature. Transformation products of TCS were characterized using HPLC/MS and quantified using HPLC/UV. Our results showed that within 1 to 5 days depending on initial TCS concentrations, 50% of TCS was rapidly polymerized into stable dimers and trimers on Fe(III)-saturated montmorillonite, while limited transformation was observed on montmorillonite surface. SPARTAN-06 quantum mechanics program was used to evaluate the most possible structural confirmation of the dimer and trimer products. Two major structural confirmations were selected for the dimer and trimer products.