Abstract

Novel amine-functionalized zirconium-based metal organic frameworks (MOFs) were solvothermally synthesized for the efficient and selective removal of Pb (II) in concentrated multi-component heavy metal ions systems. Pristine UiO-66 and UiO-67 MOFs were grafted with thiourea and amidinothiourea via a facile one-step post synthetic modification. Successful grafting was confirmed by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The microporous amidinothiourea modified MOFs demonstrated excellent performance in their high maximum adsorption capacities of 246 and 367 mg.g-1, respectively, as well as their remarkable selectivity for Pb (II) ions in highly concentrated multi-ion solutions. This is, in addition, to their effective removal efficiencies which reached up to more than 95% at a high range of Pb (II) concentrations (25 - 250 ppm). Furthermore, the structural stability of the MOF crystals was maintained after adsorption and the MOF was completely regenerated for up to four cycles. Additionally, an as-synthesized Zr-based MOF was solvothermally synthesized for the efficient removal of Diclofenac sodium (DCF) from an aqueous medium. The as-synthesized microporous DUT-67 MOF was characterized by XRD and BET. Equilibrium studies revealed that the sorption process followed the Langmuir isotherm, which accordingly demonstrated a significant adsorption capacity of 484 mg.g-1, attaining maximum removal efficiencies of about 90% at 75 and 150 ppm DCF initial concentrations. Kinetically, the adsorption process followed the pseudo-second order and the intraparticle diffusion models. The Dubinin-Radushkevich model along with thermodynamic analysis suggested a physisorption interaction that is exothermic and spontaneous.

School

School of Sciences and Engineering

Department

Chemistry Department

Degree Name

MS in Chemistry

Graduation Date

Summer 9-20-2020

Submission Date

9-20-2020

First Advisor

El-Sayed, Mayyada

Committee Member 1

Shoeib, Tamer

Committee Member 2

Nebsen, Marianne

Committee Member 3

Abd ElNaser, Anwar

Extent

125p.

Document Type

Master's Thesis

Rights

The American University in Cairo grants authors of theses and dissertations a maximum embargo period of two years from the date of submission, upon request. After the embargo elapses, these documents are made available publicly. If you are the author of this thesis or dissertation, and would like to request an exceptional extension of the embargo period, please write to thesisadmin@aucegypt.edu

Institutional Review Board (IRB) Approval

Not necessary for this item

Available for download on Tuesday, September 26, 2023

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