Journal of Thermal Analysis and Calorimetry

, Volume 133, Issue 1, pp 683–693 | Cite as

Thermal hazard analysis and combustion characteristics of four imidazolium nitrate ionic liquids

  • Wei-Cheng Lin
  • Wen-Lung Yu
  • Shang-Hao Liu
  • Shih-Yu Huang
  • Hung-Yi Hou
  • Chi-Min Shu


Thermogravimetry and differential scanning calorimetry (DSC) were used to investigate the thermal stability of four nitrate-based ionic liquids. The variations of thermal behavior for different numbers or lengths of alkyl substituents for imidazolium cations were analyzed systematically. Long-term stability and operating temperature for 1.0% mass loss during 10 h (T0.01, 10 h) were estimated using model-free perdition methodologies. The results of T0.01, 10 h were predicted to be 78.73 and 81.59 °C for [Bim][NO3] and [Mim][NO3], respectively. The apparent activation energy (Ea) was obtained using four isoconversional methods at various heating rates through DSC experiments. This study confirmed that [Bim][NO3] and [Mim][NO3] decomposed swiftly, and the gaseous products can result in ignition and continuous combustion.


Ionic liquids Long-term stability Model-free perdition methodologies Isoconversional methods Combustion 

List of symbols


Pre-exponential factor (s−1)


Degree of conversion (dimensionless)


Heating rate (°C min−1)


Apparent activation energy (kJ mol−1)


Most probable kinetic function (dimensionless)

\(\it {\text{G}}\left( \alpha \right)\)

Integral mechanism function (dimensionless)

ΔHd, avg

Average heat of decomposition (J g−1)


Universal gas constant (8.31415 J K−1 mol−1)


Temperature (°C)

T0.01, 10 h

Temperature at mass loss reaches 1.0% for 10 h (°C)


Time (min)



The authors are indebted to the Ministry of Science and Technology (MOST) in Taiwan under the Contract Number 104-2622-E-224-009-CC2 for financial support, as well as the Department of Natural Sciences Key Fund, Bureau of Education, Anhui Province, China, for its financial support under Contract Number KJ2017A078.


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Copyright information

© Akadémiai Kiadó, Budapest, Hungary 2018

Authors and Affiliations

  • Wei-Cheng Lin
    • 1
  • Wen-Lung Yu
    • 2
  • Shang-Hao Liu
    • 3
  • Shih-Yu Huang
    • 4
  • Hung-Yi Hou
    • 5
  • Chi-Min Shu
    • 4
    • 6
  1. 1.Graduate School of Engineering Science and TechnologyNational Yunlin University of Science and Technology (YunTech)YunlinTaiwan, ROC
  2. 2.Department of Industrial Education and TechnologyNational Changhua University of EducationChanghuaTaiwan, ROC
  3. 3.Department of Ammunition Engineering and Explosion TechnologyAnhui University of Science and TechnologyHuainanChina
  4. 4.Department of Safety, Health, and Environmental EngineeringYunTechYunlinTaiwan, ROC
  5. 5.Department of Occupational Safety and Health, Jen-Teh Junior College of MedicineNursing and ManagementMiaoliTaiwan, ROC
  6. 6.Center for Process Safety and Industrial Disaster PreventionYunTechYunlinTaiwan, ROC

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