Biosorption of Losartan potassium in aqueous solution on non-living microalgae Chlorella sp.

Abstract

The presence of emerging contaminants such as Losartan potassium (LP) in bodies of water can alter the physiological functions of many species, affecting not only ecosystems but also human health. In this research, the removal capacity of the LP drug in aqueous solution on the non-living microalgae Chlorella sp., was evaluated keeping the temperature and the dose of adsorbent fixed. Initially, the microalgae Chlorella sp., was grown under adequate conditions of nutrients, light and air; after its growth cycle, it was filtered and dried at 60 °C for 24 h. The bioassays were carried out applying the batch adsorption technique at different concentrations of LP (1,60 – 21,6 mg/L). In addition, scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) were performed. The results show a satisfactory fit to the Freundlich isotherm model with multilayer growth of Losartan potassium on the surface. Its maximum adsorption capacity was 1,9 mg/g, with removal percentages between 7,9 and 37,5%. Non-living Chlorella sp., shows the characteristic bands of this type of microalgae with predominance of poorly porous structures. In conclusion, non-living Chlorella sp., constitutes a potential natural adsorbent with possible use in the removal of recalcitrant emerging contaminants.