Novel Zirconium Phosphate Nanocomposite Polymeric Membrane for Effective Removal of Heavy Metals from Wastewater

Abstract

In this study, polyethersulfone/alpha-zirconium phosphate (PES/α-ZrP) and polyvinyldene fluoride/alpha-zirconium phosphate (PVDF/ α-ZrP) composite membranes were fabricated via the phase inversion method. Also, commercial cellulose membranes were surface coated with alpha-zirconium phosphate nanoparticles (α-ZrP-n). The effect of α-ZrP-n addition on the morphology, functionalities, surface charge, hydrophilicity of the membrane, among others, were investigated. Different concentrations of α-ZrP-n (0.25, 0.50, 0.75, and 1.0 wt.%) were used. The extent of α-ZrP nanoparticles was varied to evaluate their effects on the morphology, functionalities, surface charge and hydrophilicity of the membranes. The Fourier-transform infrared (FTIR) and energy-dispersive X-ray spectroscopic (EDS) analyses were performed to confirm the existence of α-ZrP-n in the fabricated membranes. It was noticed that the mixed matrix membranes became more hydrophilic after incorporating α-ZrP nanoparticles into the PES, PVDF membrane matrix. The mechanical and thermal stability as well as the porosity of PES/α-ZrP and PVDF-α-ZrP based mixed matrix membranes and cellulose coated membrane were higher when compared with pristine PVDF membrane. The well characterized membranes were used in filtration of an individual heavy metal ions (Cd2+, Cu2+, Ni2+, Pb2+ and Zn2+) solution. An overall removal efficiency of 70.2±1.0, 99.7±0.2, 81.7±1.1, 74.4±1.5, and 91.5±2.0% for Cd2+, Cu2+, Ni2+, Pb2+, and Zn2+ was reported, respectively when 0.25 wt.% of α-ZrP-n was added to the PES. While, PVDF/α-ZrP membrane comprising 0.75 wt.% α-ZrP was capable to remove heavy metal ions with removal efficiency of 86.2±5.0 (Cd2+), 99.7±0.2 (Cu2+), 81.7±2.0 (Ni2+), 99.8±1.2 (Pb2+), and 84.4±2.0% (Zn2+) from aqueous solution at neutral pH. The highest removal efficiency for cellulose membranes at neutral conditions was observed for ZrP-C4 with 61.3±2.1, 58.1±1.6, 28.7±2.1, and 15.5±1.2% for Pb2+, Cu2+, Zn2+, and Ni2+, respectively. The obtained results demonstrate the potential application of α-ZrP-n in the fabrication of advanced membranes which are efficient in the treatment of industrial wastewaters.

Date of Award	Apr 2020
Original language	American English