Efficient Adsorption of Doxycycline Hydrochloride Using Deep Eutectic Solvent Functionalized Activated Carbon Derived from Pumpkin Seed Shell
Gurleenjot Kaur, Neetu Singh, Anita Rajor
Abstract
Abstract The emerging deep eutectic solvents (DESs) are being utilized in different areas of science and engineering due to their exceptional physicochemical properties. In this study, choline chloride‐based DES was prepared in conjugation with glycolic acid (GA) as a hydrogen bond donor (HBD). Activated carbon was derived from pumpkin seed shell (PSS) using microwave‐assisted pyrolysis technique in an N 2 environment. The potential of synthesized DES was evaluated as a functionalization agent for PSSAC. DES functionalized PSSAC (DES‐PSSAC) was characterized using FTIR, XRD, FESEM and BET surface area to confirm the functionalization and identify the physico‐chemical changes. This prepared DES‐PSSAC was used as an adsorbent for the uptake of Doxycycline hydrochloride (DOX) from its aqueous solution. The influence of different process parameters was inspected in order to determine the optimal experimental conditions. At optimized parameters, the kinetics and thermodynamics studies were explored. Used DES was confirmed to be effectively grafted onto the PSSAC surface. The experimental data, best suited to the Pseudo second‐order kinetic model, whereas adsorption isotherm data were best represented by Freundlich and R‐P isotherm models. The recorded maximum adsorption capacity (q max ) was found to be 30.35 mg/g. High adsorption performance of DES‐PSSAC towards DOX uptake and its reusability exhibited that this novel adsorbent can be applied to remove pharmaceutical pollutants.