Adsorptive removal of glyphosate from aqueous solution onto pyrophyllite

Pyrophyllite was investigated in this study as a potential adsorbent for the removal of glyphosate, a common herbicide for the control of a wide variety of weeds. There are several publications in the literature that discuss how glyphosate interacts with clay minerals such as montmorillonite, kaolinite, and bentonite, but there is no information regarding the possibility of glyphosate removal from aqueous solution using pyrophyllite. In this study, the adsorption of glyphosate from water samples onto pyrophyllite, a mineral clay from the Parsovici, Konjic mine, was investigated. The ninhydrin reaction was used to spectrophotometrically quantify glyphosate. At 570 nm, the purple Ruhemman product's absorbance was determined. Adsorption capacity (qe), removal efficiency (R), and the partition coefficient are used to express the results (Kd). The outcomes demonstrated that distinct ionic species of glyphosate at different pHs cause the adsorption of glyphosate on pyrophyllite to be pH-dependent. The findings demonstrated that during different contact times, the basic medium can remove up to 75% of glyphosate. According to results from fitting isotherm models, the Freundlich model is slightly better fitted. According to the results of kinetic investigations, the pseudo-2nd order model is more suitable for this kind of adsorption.