Thesis (MSc) - Cyprus International University. Institute of Graduate Studies and Research Environmental Engineering

This study evaluates the structural properties, adsorption efficiency, and economic viability of commercial activated carbon (CAC). CAC exhibits a high apparent density (0.49 g/cm³) and significant porosity (98.13%), with a large pore volume (0.74 cm³/g) and small pore size (0.78 nm), resulting in a specific surface area of 1,052 m²/g. Additionally, the material has a low ash content (2.80%) and moisture content (3.40%). The point of zero charge (pHzpc) at pH 2.7 and a broad pore size distribution enhance its adsorption capabilities. XRD analysis indicates a lower degree of graphitisation, contributing to increased surface area and efficient adsorption. Optimal dye removal for CAC occurs at RBBR concentration of 20 mg/L, showing rapid initial adsorption and subsequent equilibrium. Statistical analysis has confirmed that the Langmuir isotherm and pseudo-second-order kinetic models best describe the adsorption process. CAC has demonstrated a high adsorption capacity of 315.69 mg/g at pH 10. From an economic perspective, CAC is purchased at approximately $10 per kilogram, with a total cost of approximately $10.50 including the operational cost (as cost per experiment is $2.12). Despite having a greater adsorption capacity of 315.69 mg/g in this study, it looks to be slightly more expensive for industrial-scale operations. CAC is costing $0.038392 per gram of dye removed. Given the increased expected cost of large-scale adsorption, certain viable and cost-effective alternatives must be investigated before being used for dye adsorption applications.