<p>Lead-acid battery industrial wastewater (LBW) laden with lead ions and other pollutants was treated in an adsorption process using sugarcane bagasse (SB) modified with α-alumina from aluminium waste cans. The SB was modified with α-alumina (α-Al₂O₃) in different proportions to fabricate adsorbents (SBAs) via wet impregnation. The SB, α-Al₂O₃, and SBAs samples were characterised to determine their suitability for adsorption. The functionality of each sample was studied through the adsorption of Pb²⁺ ions and other pollutants in the LBW. The obtained data were investigated for kinetics, isotherms, and thermodynamic parameters. The characterisation showed that the SBAs (SBA₁, SBA₂, SBA₃,&#xa0;and SBA₄) yielded structural modification due to chemical interactions between the SB and α-Al₂O₃. X-ray diffraction revealed that the α-Al₂O₃ is embedded within the fibrous structure of SB to form the SBAs. The surface area results indicated that SBA₁ (298 m²/g) has the lowest value, followed by SBA₂ (354 m²/g), and the highest is SBA₄ (552 m²/g). Among the samples, the SBA₁ performed the best for LBW treatment as the impurities reduced significantly from 1.64 to 0.25 mg/L (Pb²⁺ ions), and 692 to 486 mg/L (SO₄^2- ions). The <i>b</i>_<i>T</i>-value (1.68x10³ <i>k</i>J/mol) from the Temkin isotherm analysis confirmed that the adsorption is a chemisorption process. While ΔG^o&lt;0 indicated a thermodynamically stable and favourable process that occurs spontaneously. Therefore, the SBA₁ adsorbent has a high affinity for the Pb²⁺ ions and possesses sufficient active sites to accommodate the impurities. The SB/α-alumina is a potential cost-effective and efficient adsorbent for the remediation of LBW.</p>