Synthesis of and functionalizing MOFs by MXenes for the selective removal of lead() ions from wastewater

• Published in: RSC advances 2023-02, Vol.13 (9), p.5643-5655
• Main Authors: Ijaz, Irfan, Bukhari, Aysha, Gilani, Ezaz, Nazir, Ammara, Zain, Hina
• Format: Article
• ISSN: 2046-2069
• DOI: 10.1039/d2ra08102d

The elimination of heavy metals, especially lead, from wastewater is vital for the environment and human health and using a proper adsorbent to achieve this goal is highly desirable. Initially, Fe-THC MOF was prepared using a simple method and functionalized using MXene for efficient, rapid, and selective elimination of lead. Different characterization tools demonstrated that Fe-THC MOF and its composite Fe-THC/MXene were successfully prepared. The adsorption outcomes showed that the maximum sorption capability was 674 mg g −1 at 305 K and pH 4.5. The sorption kinetics obeys the pseudo-second-order kinetic model, and the sorption isotherms fit the Langmuir isotherm model. This finding suggests monolayer sorption on Fe-THC/MXene, and the rate-controlling step is chemisorption. Thermodynamic findings exhibit that sorption was a spontaneous and exothermic process. The sorption process can selectively adsorb Pb ions from aqueous media. After five adsorption-desorption tests, the adsorption efficiency of Fe-THC/MXene was still high. The sorption mechanism of lead on Fe-THC was mainly due to the interaction of lead ions with -F and -O ions and porosity of the Fe-THC/MXene composite. The -O and -F ions were derived from MXene, while the porosity was derived from the MOFs of composites. These findings confirmed that Fe-THC/MXene enables rapid, efficient, and selective elimination of lead from wastewater, which is of practical importance. Two different materials (MXene and MOFs) were combined to create novel Fe-THC/MXene composites as adsorbents. The prepared THC/MXene composites exhibited excellent adsorption capacity against lead.