Cation Exchange Superparamagnetic Al-Based Metal Organic Framework (Fe₃O₄/MIL-96(Al)) for High Efficient Removal of Pb(II) from Aqueous Solutions

Abstract

A cation-exchange metal–organic framework sorbent with high adsorption capacity, active anionic surface, available adsorptive sites, good response in magnetic field and also available enclosed space between the particles for encapsulation of the analyte was in situ prepared by magnetization of a metal organic framework structure of aluminum named as MIL-96­(Al). The units of magnetic MIL-96­(Al) was synthesized by embedding method under hydrothermal condition and well characterized. The mechanism of sorption can be the electrostatic interaction between the anionic structures of the adsorbent with hydrated Pb2+ ions. The high percent of OH groups on the surface of Fe3O4/MIL-96­(Al) led to high adsorption capacity (>301.5 mg g–1) of the sorbent for Pb2+ ions in aqueous media. The thermodynamic study of Pb2+ adsorption onto the sorbent surface demonstrated that the process was spontaneous, exothermic and physical. The face-centered central composite design was applied for optimizing the adsorption conditions, and the effective parameters were obtained as pH of 6.92, amount of sorbent of 32.4 mg and adsorption time of 25 min.

Fe3O4@MOF Magnetic Nanocomposites: Synthesis and Applications

“…Furthermore, due to the presence of hydroxyl groups in this structure, it became a promising choice for extraction purposes . Mehdinia and the research group designed a cation‐exchange magnetic composite by using MIL‐96(Al) and Fe 3 O 4 . This magnetic composite had an active anionic surface, reliable magnetization property, and high adsorption capacity.…”

Recent Advances in Preparation and Applications of Magnetic Framework Composites

“…Conversely, it is an excellent way to add the MNPs which has been previously formed to the solution containing the inorganic metal ions and organic ligands of the desired MOFs. According to the structure of the MFCs, this idea can be divided into: embedding method, Layer‐by‐Layer (LbL) growth method and encapsulation method . Among them, the LbL method can obtain MFCs having a core–shell structure, and usually can control the size.…”

“…The cation‐exchange Fe 3 O 4 /MIL‐96(Al) composites were also prepared through the embedding method in the hydrothermal condition . Mehdinia et al.…”

Highly efficient removal of toxic lead ions from aqueous solutions using a new magnetic metal‐organic framework nanocomposite

“…One of the known HKUST-1 is the Cu 3 (BTC) 2 MOF (BTC = 1,3,5-benzenetricarboxylate), which is one of the first stable MOFs reported with very high surface area. [14] Various methods have been developed for the removal of lead ions from aqueous solutions, including chemical precipitation, [15] ion-exchange, [16] membrane filtration technologies, [17] electroflotation technique, [18] coagulation and flocculation, [19] flotation, [20] preconcentration and extraction, [21,22] and adsorption. [12] The resulting nanocomposite has exhibit specific functional properties such as easy loading, large pores with wide windows, available coordinative unsaturated sites, high stability of chemical, rapid collection, wide surface area, as well as controllable magnetic characteristics.…”

“…Lead is one of the common contaminants of industrial wastewaters, which results from the manufacture of storage batteries, printing and painting pigments, lead glass, and dyes. [14] Various methods have been developed for the removal of lead ions from aqueous solutions, including chemical precipitation, [15] ion-exchange, [16] membrane filtration technologies, [17] electroflotation technique, [18] coagulation and flocculation, [19] flotation, [20] preconcentration and extraction, [21,22] and adsorption. [23] Adsorption method is also known as an a practical and economical procedure for lead elimination from wastewater due to easy design and operation of equipment, process reversible, and adsorbent recovery.…”