Physicochemical, Thermal and Spectroscopic Characterization of Sodium Selenate Using XRD, PSD, DSC, TGA/DTG, UV-vis, and FT-IR

Sodium selenate is an important inorganic compound but lacks reliable and accurate physico-chemical and spectral characterization information. The study was carried out for the in-depth physicochemical, thermal, and spectroscopic characterization of sodium selenate using various analytical techniques. The powder X-ray diffraction spectroscopy analysis showed well-defined and sharp peaks indicated sodium selenate is crystalline in nature. The crystallite size was found to be in the range of 28.75 to 49.97 nm. The average particle size was found to be of 3.93 (d10), 14.44 (d50), and 40.648 (d90) μm with an average surface area of 0.676 m2/g. The differential scanning calorimetry showed the endothermic inflation at 588.81 °C with the latent heat of fusion 103 J/g. The thermogravimetric analysis revealed two steps of the thermal degradation process. Similarly, the differential thermogravimetric analysis exhibited the major peaks in the thermogram and disclosed Tmax at 852.65 °C. The UV-visible spectrum showed maximum absorbance at 205.1 nm (λmax). The Fourier transform infrared spectrum showed a peak at 888 cm-1 due to the Se-O stretching. This information would be very much useful in the field of nutraceuticals/ pharmaceuticals and other industries using sodium selenate as an ingredient.