Colemanite is an important boron mineral and has different applications. In this study, a new composite material (Col/CuO/Cel) composed of colemanite, CuO, and cellulose was synthesized and investigated as a multifunctional platform for various applications. The new composite and its underlying colemanite were used in adsorption and photocatalytic degradation studies to remove crystal violet (CV) from aqueous solution. The CV adsorption of colemanite and Col/CuO/Cel was found to follow the Langmuir isotherm and the Elovich kinetic model. Furthermore, the adsorption processes were determined to be endothermic. \(\:qmax\) was calculated as 81.3 mg/g for colemanite and 57.47 mg/g for Col/CuO/Cel. Both sorbents achieved 99% adsorption efficiency. When colemanite and Col/CuO/Cel were used as photocatalysts, it was observed that the dye could be effectively degraded using a UVA lamp. While colemanite provided 95% photodegradation of the CV dye, the Col/CuO/Cel achieved 97%. During the degradation process, it was observed that colemanite followed a second-order kinetic model, while the Col/CuO/Cel composite followed a first-order kinetic model. Morphological characterization of colemanite and Col/CuO/Cel was carried out by SEM, and CuO and cellulose were observed to be dispersed in the heterogeneous colemanite structure. Structural characterization was carried out by EDX, FTIR, BET, XRD and XPS techniques. FTIR spectroscopy identified the B3-O and B4-O strains present in the colemanite structure. The crystal structure of the samples was revealed by XRD analysis. Additionally, research has shown that colemanite and Col/CuO/Cel can be used in multiple adsorption and photocatalytic degradation processes.
