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Lignocellulosic materials are an important raw material for the preparation of useful products in agriculture, such as biofuels, organic fertilizer, energy and bio-products in general. Among these materials are sawdust and barks from activities related to the primary processing of wood. This research proposes a process for the use of agroindustrial residues of wood to obtain ion exchange resins from forest wood residues to measure the absorption capacity of Pb2+. The residues were modified by chemical treatment with CS2 and NaOH, using a 0.035 residue/NaOH w/w ratio and 1.125 CS2 /residue w/w. pH tests were performed to study the influence on the ion exchange phenomenon, adsorption isotherms were also performed to evaluate the adsorption capacity of the untreated residue and the sulfonated residue. The sulfur groups of the sulfonated wood residue were identified by infrared spectroscopy (FTIR). The results showed that the best lead removal was obtained using a pH of 5 for both materials (89% and 98%) of adsorption in solutions of 100 mg L-1 of Pb2+ and 50 mg/10 mL of adsorbent, respectively. The maximum adsorption capacity of the wood residue was 65 mg g-1 of Pb2+ for the untreated residue, while for the sulfonated residue it was 72 mg g-1 of Pb2+. pH is a limiting factor for evaluating the adsorption capacity of the resin. The wood residues are useful as feedstock to obtain ion exchange resins.