Abstract
<title>Abstract</title> <p>The increasing demand for lithium has intensified interest in efficient and sustainable recovery technologies from aqueous resources. In this study, a cellulose-based composite adsorbent (Cell-HMO) was fabricated by incorporating protonated lithium manganese oxide (H₄Mn₅O₁₂) into a regenerated cellulose matrix derived from waste paper. Structural characterization using XRD, FTIR, FESEM, and EDS confirmed the successful incorporation and homogeneous distribution of HMO particles within the cellulose framework. The adsorption process was optimized using the Taguchi experimental design, which identified solution pH and adsorbent dosage as the most influential factors affecting lithium recovery. Under the optimized conditions, the Cell-HMO composite exhibited a maximum adsorption capacity of 4.842 mg g⁻¹ and a lithium recovery efficiency of 96.2%. Selectivity experiments demonstrated preferential adsorption of Li⁺ over competing K⁺ and Mg²⁺ ions, supporting the ion-sieving behavior of the composite. These findings indicate that waste-paper-derived Cell-HMO is a promising sustainable adsorbent for selective lithium recovery from aqueous solutions.</p>