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Corn and rice husks, agro-wastes available in large quantities in Tanzania, were used to remove Pb²⁺ from aqueous solution. Husks were used in raw form, pyrolyzed form, and chemically modified form. Material characterization was carried out using the BET method, FTIR spectroscopy, SEM, pH_PZC, and cation exchange capacity analysis. Langmuir, Freundlich, Dubinin-Radushkevich (D-R), and Temkin isotherms were used to elucidate Pb²⁺ sorption mechanisms. The surface area and cation exchange capacity (CEC) of untreated and chemically treated biochars were significantly higher than that of raw husks. Sorption data for Pb²⁺ for all biosorbents fit the Freundlich and D-R models well with high R² values. Most of the synthesized biosorbents in this study indicated >90% for Pb²⁺ removal, with the ZnCl₂-treated corn husk biochar sorption capacities ranking highest in all modeling results. Surface …