Removal of Paracetamol from Aqueous Solutions Using Activated Carbon Obtained from Methane Pyrolysis-Derived Carbon Black

Paracetamol (PCT), along with other pharmaceutical pollutants, increasingly requires removal from wastewater, whereas carbon black produced via methane pyrolysis can serve as a reliable and sustainable carbon source for the corresponding sorbents. This study evaluates the effect of CO2-based high-temperature activation parameters (temperature, duration, feed mass, composition of the activating gas) on the morphology, pore architecture, and PCT adsorption performance of activated carbon obtained from methane pyrolysis-derived carbon black. The sorption capacity of the activated carbon with respect to PCT, as well as the effect of initial pH (5–9) on adsorption isotherms and kinetics were studied. Among the investigated activation conditions (800–1000 °C, 60–180 min and different feed masses), the best-performing material exhibited a BET surface area of 712 m2·g−1 and a total pore volume of 0.44 cm3·g−1 (predominantly slit-shaped mesopores) and was obtained at 1000 °C for 180 min using a mass of 5.65 g. The resulting sorbent exhibits a PCT capacity of 629 mg·g−1 in a neutral medium and 718 mg·g−1 at pH 5. A physisorption mechanism with an adsorption energy of less than 8 kJ·mol−1 was shown. The kinetics of sorption obeyed a pseudo-second-order model with equilibrium within 5 min. The results demonstrated the potential of using activated carbon produced from carbon black (a product of methane pyrolysis) to remove pharmaceutical contaminants from water.