A green adsorbent based on wheat starch for removal of selective organic pollutants from aqueous solutions

Abstract

The objective of this study was to evaluate the adsorption efficiency of a cationic functionalized wheat starch, obtained with betaine hydrochloride and glycidyl trimethylammonium chloride by an environmentally friendly process without the use of organic solvents. Surface functional groups of samples were characterized by Fourier transform infrared spectroscopy, the morphology of the materials was examined using scanning electron microscopy, the nitrogen content was determined by elemental analysis, while UV-VIS spectroscopy and liquid chromatography-tandem mass spectrometry were used for adsorption investigation. The efficiency of obtained cationic starches to adsorb the anionic and cationic dyes, as well as selected pharmaceuticals and pesticides was investigated. Adsorption experiments were performed in a batch system to determine the effect of contact time, initial concentration, and pH of the solution on the removal efficiency of crystal violet dye, which was chosen as the model for the detailed study of adsorption. Pseudo-first and pseudosecond order models were used to examine the adsorption kinetic, while Langmuir and Freundlich isotherm models were applied to equilibrium adsorption data. The results showed that environmentally and economically acceptable adsorbents prepared in this study could be effective in removing the examined organic pollutants.