Development of bioadsorbents from fennel seeds and thapsia roots for the treatment of dyes in wastewater

Abstract

The aim of this work is to exploit two bio-adsorbents, namely fennel seeds and sweet thapsia roots, for the adsorption of pharmaceutical pollutants such as chlortetracycline HCl (CTCHCl) and methylene blue (MB). Biological activation of fennel seeds was carried out, and a comparison between activated and non-activated seeds revealed improved results in terms of the quantity adsorbed at equilibrium. Experimental designs were applied to optimise the adsorption conditions, and adsorption isotherm modelling was carried out using 32 models optimised by the Dragonfly algorithm. The results give a maximum adsorption capacity of 296.43 mg/g and 179.39 mg/g for the bio-fibres resulting from the biological treatment of fennel seeds (FBIO) and fennel seeds (FEN) respectively.