The functionalization of biochar offers several advantages, including enhanced adsorption capacity for contaminants, improved nutrient retention and release in soils, increased catalytic activity, and customized properties for specific applications . Surface functionalization is apparently one approach to improve biochar's adsorption utility. Surface oxidation is one way for anchoring specific functionalities such as oxygen-holding functional groups to biochar for generating functional biochar for the removal of high intensity dye substances . Many studies have revealed methods for surface functionalizing biochar, such as sulfonation and limited oxidation, to create surface functionalized biochar with increased attraction for specific pollutants. Many methods for treating dye containing wastewater have been developed in recent years, which includes Flocculation and coagulation