The adsorption results presented in this study suggests that the SFHAC is a very promising adsorbent with high active surface area for the removal of herbicide bentazon. SEM analysis showed that prepared ACs are mesoporous in nature and FTIR analysis confirmed several active functional groups on the surface of the SFHAC. The adsorption capacity at equilibrium increases with increasing initial concentration of bentazon and the amount of bentazon adsorbed by SFHAC decreases with increasing solution pH. The adsorption isotherm was well fitted by the Freundlich
model than Langmuir model, indicating heterogeneous surface structure. The maximum adsorption capacity was found to be 166.67 mg/g. The positive value of enthalpy change (DH) confirms that adsorption process was endothermic in nature. Finally, it may be concluded that the SFHAC can provide a further insight into the removal of other pesticides in adsorption system.