Estudio de remoción de cafeína de aguas sintéticas utilizando humedales subsuperficiales de flujo vertical : Estudio de la remoción de cafeína mediante el uso de humedales subsuperciales de flujo vertical utilizando PET recicldo como medio de soporte

Abstract

The introduction of emerging contaminants into the environment, such as caffeine, has a significant impact on aquatic ecosystems, causing disruptions to living organisms and environmental balance. In response, constructed wetlands with vertical subsurface flow used to treat a synthetic solution containing 30 ppm of caffeine, utilizing polyethylene terephthalate (PET) obtained from plastic bottles as a supporting medium. Additionally, the influence of ornamental plants Dracaena fragrans in the system was investigated through duplicate trials with (R1 and R2) and without (R3 and R4) plants. The wetlands were operated in batch mode with a HRT of 7 days, receiving a 16 L volume of caffeine solution per drip in one hour, over a period of 10 weeks. Removal efficiencies were quantified using UV-VIS spectrophotometry and, at the same time, physicochemical parameters of water quality were analyzed to monitor wetland performance. The study found that PET is an effective support medium for caffeine removal, because promoting biofilm formation, achieving removal rates at day 7 of 99%, 98%, 97% and 92% for R4, R1, R2, and R3, respectively. In accordance with these results, it was statistically demonstrated that vegetation had no significant impact on system efficiency (p<0.05). Water quality parameters did not change significantly, as they were below the LMP during the experimentation.