Thermophysical properties of neat and radiolytically degraded acidic extractants present in room temperature ionic liquid

  • Ch. Venkateswara Rao
  • Alok Rout
  • Satyabrata Mishra
  • K. A. VenkatesanEmail author


The thermophysical properties of a couple of acidic extractants, namely bis(2-ethylhexyl)phosphoric acid (D2EHPA) and bis(2-ethylhexyl)diglycolamic acid (HDEHDGA), dissolved in the room temperature ionic liquid diluent 1-butyl-3-methylimidazolium bis(trifluoromethanesulphonyl)imide ([C4mim][NTf2]) were investigated. The physical properties such as density, viscosity, and refractive index were measured as a function of various parameters such as temperature, concentration of extractant, and concentration of nitric acid. The viscosity of the gamma-ray irradiated solution composed of 0.06 M D2EHPA/[C4mim][NTf2] and 0.06 M HDEHDGA/[C4mim][NTf2] was compared with unirradiated solution. The phase separation time (PST) was determined for both irradiated and unirradiated samples after acid equilibration. Thermogravimetry analysis was carried out for the solvent system composed of D2EHPA, HDEHDGA, [C4mim][NTf2], and 0.06 M D2EHPA(or HDEHDGA)/[C4mim][NTf2] to understand the thermal stability of the ionic liquid system.


Ionic liquid Bis(2-ethylhexyl)phosphoric acid Bis(2-ethylhexyl)diglycolamic acid Density Viscosity Irradiation 



The author (Dr. K. A. Venkatesan) thanks Board of Research in Nuclear Sciences for funding the project under the scheme DAE-SRC-OI project number: 21/09/2015-BRNS/35040. The authors thank Dr. N. Sivaraman, Head, Fuel Chemistry Division for the keen interest in the present study.


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© Akadémiai Kiadó, Budapest, Hungary 2019

Authors and Affiliations

  1. 1.Homi Bhabha National InstituteMumbaiIndia
  2. 2.Fuel Chemistry DivisionIndira Gandhi Centre for Atomic ResearchKalpakkamIndia
  3. 3.Reprocessing Research and Development DivisionIndira Gandhi Centre for Atomic ResearchKalpakkamIndia

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