Mechanistic Adsorption Modeling and Cost Analysis for Integrated Batch and Continuous-Flow Performance of Sustainable Forestry Waste-Derived Activated Carbons for Pharmaceutical Removal

Activated carbons (ACs) derived from pine cones and pine needles feedstock were tested as cost-effective and high-efficiency solutions for the removal of diclofenac (DCL), atenolol (ATE), and ketoprofen (KETO) from wastewater. Characterization techniques were used to investigate the surface characteristics and morphology of the activated carbons: nitrogen porosimetry, SEM (Scanning Electron Microscopy), and EDS (Energy Dispersive Spectroscopy). The adsorption mechanism was further investigated using FTIR (Fourier Transform Infrared Spectroscopy). Activity-Based Costing (ABC) method was utilized for adsorbent’s cost analysis. Adsorption batch experiments were conducted to study the effect of pH, contact time, initial concentration, temperature, and adsorbent dosage), and the optimum adsorbent was used as packing material for a lab-scale adsorption column. According to the results, the optimum removal was achieved by pine cone AC calcined at 500 °C (AC@PC500) at pH 5 for DCL (99.8%) and pH 3 for KETO (99.2%) adsorption. For ATE, the highest removal (97.1%) was achieved at pH 7. Pseudo-second-order and Langmuir models fitted better with the experimental results, providing an outstanding maximum adsorption capacity of 344, 371, and 130 mg g–1 for DCL, KETO, and ATE adsorption, respectively. Column experiments provided a notably high adsorption capacity for continuous flow operations: 18.8 and 67.84 mg g–1 for DCL and KETO removal. The findings revealed that this streamlined approach costs 0.71 €/g. Overall, activated carbons from pine cones and pine needles can serve as a highly effective, affordable, and sustainable approach for the removal of pharmaceuticals from wastewater.