Highly rapid and efficient removal of heavy metals, heavy rare earth elements, and phenolic compounds using EDTA-cross-linked MXene polymer composite: Adsorption characteristics and mechanisms

Recovery of heavy metals, heavy rare earth elements, and phenolic compounds from industrial water has attracted attention due to their ecological toxicity and their larger demand for advanced technologies. We herein synthesize a novel EDTA-cross-linked MXene polymer composite for the removal of lead (II), holmium (III), and hydroquinone. The structure, morphology, and sorption performance of the EDTA-cross-linked MXene polymer composite were explored comprehensively. The correlation coefficients (R2) of the PSO kinetic model for lead (II), Ho (III), and hydroquinone were 0.9999 and greater than those of the PFO kinetic model when comparing the R2 derived by fitting the two kinetic models. EDTA-cross-linked MXene polymer composite rapidly removed the heavy metals, heavy rare earth metals, and phenolic compounds, such as lead (II), holmium (III), and hydroquinone within 5, 8, and 10 min, respectively. The sorption isotherm of lead (II), holmium (III), and hydroquinone might be explained well by the Langmuir model, and the maximum sorption capabilities (qmax) were derived as 893.92 mg/g for lead (II), 809.37 mg/g for Ho, and 754.09 mg/g for HQ, respectively. The adsorbed composite could easily be regenerated and can be utilized 19 times without a significant impact on its sorption performance. The synthesized adsorbent also exhibits remarkable sorption performance for other heavy metals (Cd, Cr, Ca, Mg, Ba, and Ni), rare earth metals (Eu, Yb, Er, Lu, Tm, and Y), and phenolic compounds (catechol and resorcinol). This research work provides a new EDTA-cross-linked MXene polymer composite for the excellent elimination of lead, holmium (III), and hydroquinone.