Fluoxetine and Nutrients Removal from Aqueous Solutions by Phycoremediation

Andreia D M Silva; Diana F Fernandes; Sónia A Figueiredo; Olga M Freitas; Cristina Delerue-Matos

doi:10.3390/ijerph19106081

Fluoxetine and Nutrients Removal from Aqueous Solutions by Phycoremediation

Int J Environ Res Public Health. 2022 May 17;19(10):6081. doi: 10.3390/ijerph19106081.

Authors

Andreia D M Silva¹, Diana F Fernandes¹, Sónia A Figueiredo¹, Olga M Freitas¹, Cristina Delerue-Matos¹

Affiliation

¹ REQUIMTE/LAQV-Associated Laboratory for Green Chemistry (LAQV) of the Network of Chemistry and Technology (REQUIMTE), Instituto Superior de Engenharia do Porto-Politécnico do Porto, Rua Dr. António Bernardino de Almeida 431, 4249-015 Porto, Portugal.

Abstract

The tertiary treatment using microalgae offers an attractive alternative to the removal of low but relevant concentrations of pharmaceuticals from domestic wastewaters. The removal of fluoxetine from aqueous solutions by living and non-living (lyophilized) Chlorella vulgaris was assessed. The determination of the pH at the point of zero charge, Fourier transmittance infrared analysis, and scanning electron microscopy were performed to characterize the microalgae biomass. Kinetic and equilibrium experiments were performed. The pseudo-second-order model described the kinetics of fluoxetine. The corresponding kinetic constants indicated that biosorption was faster onto non-living biomass than onto living biomass. The equilibrium results showed that the systems followed the Langmuir isotherm model. The maximum capacity of living microalgae (1.9 ± 0.1 mg·g^-1) was slightly higher than the non-living microalgae (1.6 ± 0.2 mg·g^-1). Living Chlorella vulgaris, free and immobilized in calcium-alginate, were also used to remove fluoxetine and nutrients (nitrogen and phosphorus) from treated municipal wastewater in a batch system. In both experiments, fluoxetine was completely removed within six days. The total phosphorus (TP) and total nitrogen (TN) removal efficiencies achieved for free and immobilized cells were, null and 65.0 ± 0.1%, and 86.2 ± 0.1% and 81.8 ± 3.1, respectively.

Keywords: Chlorella vulgaris; domestic wastewater; immobilization; nutrients; pharmaceuticals; tertiary treatment.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Adsorption
Chlorella vulgaris*
Fluoxetine
Microalgae*
Nitrogen
Nutrients
Phosphorus
Water / chemistry
Water Pollutants, Chemical* / chemistry

Substances

Water Pollutants, Chemical
Fluoxetine
Water
Phosphorus
Nitrogen

Grants and funding

This research was funded by the Associate Laboratory for Green Chemistry-LAQV, which received financial support from UIDB/50006/2020, UIDP/50006/2020, and LA/P/0008/2020 by the Fundação para a Ciência e a Tecnologia (FCT)/Ministério da Ciência, Tecnologia e Ensino Superior (MCTES) through national funds. This research was also funded by the EU and FCT/UEFISCDI/FORMAS, in the frame of the collaborative international consortium REWATER—“Sustainable and safe water management in agriculture: increasing the efficiency of water reuse for crop growth while protecting ecosystems, services and citizens’ welfare” (WaterJPI/0007/2016), which was financed under the ERA-NET Co-fund WaterWorks2015 Call, as an integral part of the 2016 Joint Activities developed by the Water Challenges for a Changing World Joint Program Initiative (Water JPI). The research was funded also by FCT and BiodivRestore Joint Call 2020–2021-European Union’s Horizon 2020 research and innovation program under grant agreement No. 101003777-BiodivRestore-406/DivRestore/0002/2020-BioReset-“Biodiversity restoration and conservation of inland water ecosystems for environmental and human well-being”. A.D.M. Silva would like to thank FCT for her Ph.D. Grant SFRH/BD/138/780/2018. The authors are greatly indebted to all financing sources. The authors are grateful to Materials Centre of the University of Porto (CEMUP), Porto, Portugal, for expert assistance with SEM/EDS.