A tailored metal–organic framework applicable at natural pH for the removal of 17α-ethinylestradiol from surface water
Parisa Javidan, Majid Baghdadi, Ali Torabian, Behnoush Aminzadeh
Abstract
ABSTRACT The use of metal–organic frameworks as efficient adsorbents for micropollutants removal has attracted significant interest recently, while the effect of linkers on their performance was not examined extensively. The present paper was devoted to examining the removal of 17α-ethinylestradiol (EE2), a synthetic hormone with high-potency estrogenic contamination, from surface water by adsorption process using MIL-53(Fe) and NH 2 -MIL-53(Fe) as metal–organic frameworks adsorbents constructed with different linkers. Batch experiments were designed using the Design-Expert software by considering the effective parameters, including the initial concentration of EE2, adsorbent dosage, and pH. The effects of total dissolved solids and temperature were investigated as well. The adsorbent synthesis was done by the solvothermal method, and field-emission scanning electron microscopy, X-ray diffraction, Fourier-transform infrared spectroscopy, Brunauer– Emmett–Teller, and energy-dispersive X-ray spectroscopy analyses were performed to evaluate the characterization of the prepared adsorbent. The results of characterizations showed the crystalline structure of NH 2 -MIL-53(Fe) with a high specific surface area of 743 m 2 /g. According to the preliminary tests, NH 2 -MIL-53(Fe) was more efficient than MIL-53(Fe), especially in natural waters with neutral pH. In the case of using 2-aminoterephthalic acid as a linker, in addition to Van der Waals attraction, electrostatic interaction is involved in the adsorption of EE2 and improves removal efficiency. The easy regeneration and reusability of NH 2 -MIL-53(Fe) for several cycles make it suitable for EE2 removal in natural water resources.