Fabricating modified carbon sesame straw for adsorption of acetaminophen and ibuprofen from aqueous media: isotherm and kinetic models.

As acetaminophen (ACT) and ibuprofen (IBP) have serious environmental impacts, despite their widespread use in many countries, the present research examined the effectiveness of activated carbon made from straw and sesame stubble in removing ACT and IBP from water. To that end, the as-synthesized adsorbent was functionalized using zinc chloride. The maximum adsorption capacities were found to be 51.7 mg g for ACT and 63.7 mg g for IBP. The adsorption kinetics and isotherm results showed that the pseudo-second-order (PSO) kinetics and Langmuir isotherm fit the data obtained from this study better than the other experimental models do. Also, the adsorption reached equilibrium within 120 min, and the optimal adsorbent dose and temperature were obtained as 1.0 mg and 25 °C, respectively. The mechanisms involved in the adsorption process would include acid-base, hydrogen bonding, electrostatic forces, and π-π interaction. Reusability studies revealed that the adsorbent still preserved about 89% and 82% of the adsorption performance for ACT and IBP, respectively, after seven repeated adsorption cycles. As the findings indicated, CSS/Zn could be accepted as a hopeful adsorbent to be used in pharmaceutical treatment.