Physicochemical, Thermal and Spectroscopic Characterization of Sodium Selenate Using XRD, PSD, DSC, TGA/DTG, UV-vis, and FT-IR 1. INTRODUCTION

Abstract

Sodium selenate is an important inorganic compound, but

lacks reliable and accurate physico-chemical and spectral

characterization information. This article described the

in-depth physicochemical, thermal, and spectroscopic

characterization of sodium selenate using various analytical

techniques. The powder X-ray diffractogram showed welldefined,

narrow and sharp peaks indicating that 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 40.65 (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. This indicated sodium selenate thermally more

stable in nature. 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.

These information would be very much useful in the field of

nutraceuticals/ pharmaceuticals and other industries using

sodium selenate as an ingredient.

Keywords

• Sodium selenate,Crystallite size,Particle size,Thermal analysis

Sodyum selenat’ın XRD, PSD, DSC, TGA/DTG, UV-VIS ve FT-IR yöntemleri ile fizikokimyasal, termal ve spektroskopik karakterizasyonu

Abstract

Önemli bir inorganik bileşik olan sodium selanat’ın

fizikokimyasal ve spektral yöntemlerle karakterizasyonuna

dair kesin ve güvenilir veri bulunmamaktadır. Bu makale,

sodium selenat’ın çeşitli analitik yöntemler kullanılarak yapılan

fizikokimyasal, termal ve spektroskopik karakterizasyonu

ile ilgili geniş kapsamlı veri içermektedir. Toz X-ışını

difraktogramı, sodyum selenatın kristal yapıda olduğunu

gösteren iyi tanımlanmış, dar ve keskin zirveler göstermiştir.

Kristalit boyutu 28.75 - 49.97 nm aralığında bulunmuştur.

Ortalama partikül boyutu 3.93 (d10), 14.44 (d50), ve 40.65

(d90) μm, ortalama yüzey alanı 0.676 m2/g’dır. Diferansiyel

taramalı kalorimetre kullanılarak yapılan çalışmalarda 588.81

°C’de endotermik şişkinlik gösteren sodium selenat’ın gizil

füzyon ısısı 103 J/g olarak tespit edilmiştir. Termogravimetrik

çalışmalar, sodium selenat’ın termal bozunma sürecinin iki

basamaklı olduğunu göstermiştir. Benzer şekilde, diferansiyel

termogravimetrik analizlerde de termogramda iki ana pik ve

852.65 °C’de Tmax tespit edilmiştir. Bu sodyum selenatın doğada

termal olarak daha kararlı olduğunu gösterdi. UV-görünür

spektrum, 205.1 nm’de (λmax) maksimum absorbans gösterdi.

FT-IR spektrumunda, 888 cm-1’de Se-O gerilme titreşimlerine

atfedilen bir band görülmüştür. Bu bilgiler, nutrasötikler / ilaçlar

ve bir bileşen olarak sodyum selenat kullanan diğer endüstriler

için çok yararlı olacaktır.

Keywords

• Sodyum selenat,Kristalit boyutu,Parçacık boyutu,Termal analiz,Yüzey alanı

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