Adsorption of dypirone from aqueous solution using Moringa oleifera seed husks
Currently, the monitoring of pharmaceuticals in the environment has been highlighted because they are frequently found in waste water treatment plant (WWTP) effluents and surface waters, since conventional treatment is often not sufficient for its total removal. Considering this impact, the present study sought to evaluate the adsorption capacity of these contaminants by Moringa oleifera seed husks (MO), an agroindustrial residue, after three chemical treatments followed by thermal treatment, with a simple heating in an air furnace at 300°C for 1 h. The chemical treatments were performed through the contact of 30 mg of MO with 1 L of the respective reagent for 3 h in a mechanical stirrer. The reagents tested were: methanol 0.1 M followed by nitric acid 0.1 M (MOMA), phosphoric acid 0.1 M (MOA) and sodium hydroxide 0.1 M (MOB). The highest adsorption capacity was obtained with MOB (10.24 mg g‑1, relative to 74.50% of removal), but the color released by the biosorbent resulted in false concentrations of dipyrone up to 7.46 mg g‑1. MOMA obtained the lowest value (2.66 mg g‑1, relative to 19.13% of removal) and MOA obtained a value of 5.65 mg g‑1 (40.72% of removal), and its biggest advantage was the absence of color interference, allowing quantifying the actual concentration of dipyrone.
Quesada, H.B., Cusioli, L.F., de Araújo, Á.A., Gomes, R.G. and Bergamasco, R. (2021). Adsorption of dypirone from aqueous solution using Moringa oleifera seed husks. Acta Hortic. 1306, 285-292
emerging pollutants, pharmaceuticals, water treatment