
Urea-Assisted Synthesis of Nanospherical and Plate-Like Magnesium Oxides for Efficient Removal of Reactive Dye Wastes
Author(s) -
H. M. S. P. Randiligama,
M.M.M.G.P.G. Mantilaka,
T. C. Palihawadana
Publication year - 2020
Publication title -
journal of nanomaterials
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.463
H-Index - 66
eISSN - 1687-4129
pISSN - 1687-4110
DOI - 10.1155/2020/6189061
Subject(s) - materials science , thermogravimetric analysis , calcination , adsorption , scanning electron microscope , magnesium , fourier transform infrared spectroscopy , chemical engineering , transmission electron microscopy , oxide , pulmonary surfactant , inorganic chemistry , catalysis , organic chemistry , composite material , nanotechnology , chemistry , metallurgy , engineering
Nanospherical and plate-like magnesium oxide has been successfully synthesized by urea precipitation method for the first time. A magnesium oxide precursor was prepared by heating MgCl2 solution with urea for 12 hours at 90°C. Then the calcined precursor was analysed by Scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, thermogravimetric analysis (TGA), and high-resolution transmission electron microscopy (HR-TEM). In the presence of the nonionic surfactant Triton X-100 in the system, the reaction yielded in nanospheres of MgO contrast to the plate-like MgO in the absence of the surfactant. The precursor and the calcined product appeared in similar morphologies under SEM in both cases with a slight reduction of size upon calcination. The final product was confirmed as MgO using XRD and FT-IR spectroscopic methods. In TGA, both samples showed similar mass loss values upon elimination of adsorbed water molecules and decomposition of the precursor into MgO; however, the nanospherical MgO sample showed an additional weight loss due to elimination of the associated surfactant molecules. The efficiency of removing reactive dye wastes was quantified by UV-visible spectroscopy using reactive yellow dye. Plate-like MgO showed a porous structure under HR-TEM analysis in the dye adsorption study, and both plate-like and nanospherical MgO showed good dye adsorption capability. MgO nanospheres showed higher capacity of dye adsorption compared to plate-like MgO, explained by its higher surface are-to-volume ratio, while the plate-like MgO also performed well due to having a nanoporous structure. These nanomaterials will offer high potential in purifying waste water and as well in recovering expensive dye products.