Lead (II) pollution from the various industries is a serious environmental problem that requires urgent attention due to its stability and non-biodegradability. Current research addresses the development of a natural polymer's chemical structure to produce an absorbent nanocomposite for lead removal. This development relied on the available functional groups (amino-NH₂ and hydroxyl-OH groups) in biopolymers to create adsorbent material through two steps. The first step was chemical bonding of chitosan with glutaraldehyde as a crosslinking agent (CT-GLA) using emulsion cross linking technique, followed by another bonding with a heterogeneous organic compound to provide additional functional groups (CT-GLA-PD). The second step involved supporting the compound with copper oxide nanoparticles (CT-GLA-PD-Cu) to improve characterizations of the adsorbent. The chemical structure of the materials prepared by paraffin dispersion followed by nanoparticle support was carried out in the current study to explain the functional groups that disappeared and formed during the preparation stages. The surface characterization and chemical composition of the adsorbent resulting from the two stages were performed using advanced descriptive techniques such as Fourier Transform Infrared spectroscopy, X-ray Diffraction, Field Emission Scanning Electron Microscope and Energy Dispersive X-ray. According to the experimental data, the chemical modification showed a significant enhancement in morphology properties and composition elements, which positively impacted removal efficiency. This structure development has been reflected in the lead removal efficiency compared to the raw adsorbent. The results showed that the adsorbent produced in the first stage achieved acceptable lead removal efficiency. This performance was further doubled after the use of nanoparticles as supporting material in the second stage.