Production of Activated Carbon Using RSM‐BBD Optimization Design With H ₃ PO ₄ Activation From Cornelian Cherry ( Cornus mas<

A two‐stage research design was conducted in this study. In the first stage, activated carbon production from cornelian cherry seeds using phosphoric acid was optimized using the Box–Behnken design within the scope of the surface response method. Acid concentration (45–85%w), activation temperature (350°C–650°C), and impregnation ratio (1/1–1/3 acid/substance) were evaluated as experimental factors. As a result of the optimization, the activated carbon synthesized under the most favorable conditions (82.3% w acid concentration, 650°C activation temperature, and 2.3 acid/substance impregnation ratio) was found to have a high specific surface area of 899.82 m ² /g. The produced activated carbon was characterized in detail by SEM, FTIR, BET, and pH _pzc analyses. In the second stage, the performance of the obtained activated carbon in the removal of Cu(II) ions was investigated by batch adsorption experiments. The effects of parameters, such as pH (2–6), initial Cu(II) concentration (50–250 mg/L), adsorbent dose (0.05–0.35 g), and temperature (25°C–55°C), on the removal efficiency were investigated. The adsorption data were applied to the Langmuir, Freundlich, and Temkin isotherm models as well as pseudo–first‐order, pseudo–second‐order, Elovich, and intraparticle diffusion kinetic models. The results showed that the adsorption process of Cu(II) was best described by the Langmuir isotherm ( q _m  = 389.01 mg/g) and the pseudo–second‐order kinetic model.