Purification and Characterization of High Purity Nano Zirconia by Liquid-Liquid Extraction Using D2EHPA/p-Xylenes

Abstract

In this paper, Zr(IV) nitrate solution decomposed from Viet Nam zircon concentrate was the source of zirconium extraction by liquid-liquid extraction (L.L.E). The FT-IR and UV-Vis spectra confirmed the extraction of Zr(IV) by D2EHPA/p-xylenes. There were four stages for the purification of impurities from the Zr matrix. First, the extraction of elements in 3.0 M HNO3 by 50% D2EHPA/p-xylenes was conducted. Second, two scrubbing cycles of impurities using 6.0 M HNO3, 76.5% of the total amount of Zr(IV) were retained in the organic phase, and 23.5% remained in the aqueous phase. Third, the stripping of a macro amount of zirconium from loaded D2EHPA has been effectively carried out using 1.5 M H2SO4 with a stripping efficiency of 99.6%. Fourth, concentrated ammonia was added to the solution Zr(IV) after stripping extraction to form precipitate for calcination at 550 °C for the final products. The refined products were characterized by X-ray diffraction, scanning electron microscopy (SEM), transmission electron microscopy (TEM), EDS, XRF, and diffuse reflectance spectroscopy. The ZrO2 has high purity, is nanospherical, and has a uniform sphere-like morphology with small grain size of less than 30 nm and a bandgap value of about 3.30 eV.

Antibiofilm and Anti-Quorum Sensing Potential of Safely-Synthesized Hydrated Zirconium Oxide-Coated Alginate Beads against Some Pathogenic Bacteria

“…Other prominent monoclinic zirconia peaks occurred at 2θ angles 28.1, 35.6, 39.8, 45.6, 49.6, 54.2, 55.3, 57.0, 60.2, 68.1, 74.0, and 76.5 in conformity with reported data [73][74][75]. Te peaks at 2θ 20.06 °and 28.96 °are attributable to calcium alginate [75,76]. Most of the important peaks of ZAB-1 and ZAB-2 are in agreement with those of ZrO 2 with the dominant monoclinic phase [77][78][79].…”

“…Te characteristic XRD difraction peak of the monoclinic zirconia phase appeared at 28.1 °and there was an absence of a tetragonal zirconia difraction peak at 30 °, suggesting an almost monoclinic nature [71,72]. Other prominent monoclinic zirconia peaks occurred at 2θ angles 28.1, 35.6, 39.8, 45.6, 49.6, 54.2, 55.3, 57.0, 60.2, 68.1, 74.0, and 76.5 in conformity with reported data [73][74][75]. Te peaks at 2θ 20.06 °and 28.96 °are attributable to calcium alginate [75,76].…”