Resumen
Glyphosate is an herbicide that is usually used by farmers and is considered harmful to the environment in excess amounts. To address these issues, coffee-husk-biochar-loaded Fe3O4 (CHB- Fe3O4) was used as an adsorbent to remove glyphosate from water. CHB-Fe3O4 characteristics such as pHpzc, FTIR, and SEM were measured to understand the properties of this adsorbent. The best conditions for glyphosate removal by CHB-Fe3O4 were obtained at pH 2.0, where the adsorption capacity and percentage removal are 22.44 mg/g and 99.64%, respectively, after 4 h of adsorption. The Freundlich model provided the best fit for the adsorption isotherm, demonstrating multilayer sorption. The most effective model for characterizing the adsorption kinetics was the pseudo-second-order model with a chemical adsorption mechanism. The desorption studies found that the use of 0.1 M NaOH was the best concentration to effectively desorb glyphosate with a desorption percentage of 69.4%. This indicates that CHB- Fe3O4 is a feasible adsorbent for glyphosate removal from water.