Naphthalene and carbendazim removal in constructed wetlands using vetiver and jute: mechanistic insights and practical implications

The study presents the implementation of a constructed wetland system utilizing vetiver (<i>Chrysopogon zizanioides</i>) and jute (<i>Corchorus olitorius</i>) for attenuating aqueous naphthalene and carbendazim. The removal efficiencies for naphthalene were 90.25%, 78.27%, 82.97%, 85.11%, and 92.38%. Similarly, for carbendazim, they were 91.84%, 70.06%, 81.46%, 79.41%, and 80.45% in batch studies for raw and dried vetiver leaves, roots, and jute. The maximum sorption capacity ranged between 0.3825 and 2.2227 mg/g. A change in pH in the range of 2-10 resulted in decreased carbendazim sorption (maximum of 80% at pH = 2; minimum of 16% at pH = 10), while negligible change was observed for naphthalene. Temperature elevation from 5 to 45 °C led to enhanced removal efficiency for both naphthalene (23% at 5 °C to 95% at 45 °C) and carbendazim (16% at 5 °C to 93% at 45 °C) across all sorbents. In wetlands with only vetiver, average removal efficiencies over a 9-day experiment were 89.71% and 83.05% for naphthalene and carbendazim, respectively. Incorporating jute further improved the removal efficiencies to 96% and 94.8%, respectively, over 30 days. The outcome proves that constructed wetlands with vetiver, and jute might efficiently attenuate hazardous contaminants like naphthalene and carbendazim in wastewater, which is significant from a social health perspective.