Analysis of thermodynamic characteristics of imidazolium-based ionic liquid on coal

  • Zujin Bai
  • Caiping WangEmail author
  • Jun Deng


To investigate the effects of ionic liquids (ILs) on the oxidative combustion characteristics of coal, the oxidation characteristics of ILs on coal, such as characteristic temperature, thermal mass loss rate, and oxidation kinetics characteristic parameters, were determined. The results the [BMIm][I]-treated coal samples increased cracking temperature (T1), maximum oxidization mass gain (T2), ignition temperature (T3), burnout temperature (T4), minimum thermal rate (Ta), maximum thermal energy (Tb), and maximum thermal rate (Tc) by 33.2, 29.3, 20.7, 42.8, 11.4, 23.0, and 27.9 °C, respectively. The increase mass ratio of coal samples treated with ILs increased and decreased at the water evaporation and thermal decomposition stages, respectively. The apparent activation energy (Ea) of coal samples treated with ILs increased, and the mechanism function also changed accordingly. These showed that the ILs improved the thermal stability of the coal samples in the stages of absorbing oxygen and increased mass, and the loss of combustion. The ILs caused damage to the molecular structure of the coal and ultimately effected changes in the combustion performance. In addition, the [BMIm][BF4] hardly weakens the inhibitory effectiveness of the coal sample over time; coal spontaneous combustion could be effectively inhibited.


Oxidation characteristics Thermal stability Combustion properties Inhibitory effectiveness Coal spontaneous combustion 



This work was sponsored by the National Key Research and Development Plan of China (No. 2018-YFC-0807900), National Natural Science Foundation of China (No. 51974234, 51974233, 51974236, and 51974235), the Shaanxi Province Innovative Talent Promotion Plan-Youth Science and Technology New Star Project (No. 2019KJXX-050), the Excellent Youth Science and Technology Fund Project of Xi’an University of Science and Technology (No. 2019YQ2-03), and Key Research and Development Program of Shaanxi Province (No. 2017ZDCXL-GY-01-02-03).


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Copyright information

© Akadémiai Kiadó, Budapest, Hungary 2019

Authors and Affiliations

  1. 1.School of Safety Science and EngineeringXi’an University of Science and Technology (XUST)Xi’anPeople’s Republic of China
  2. 2.Shaanxi Key Laboratory of Prevention and Control of Coal FireXUSTXi’anPeople’s Republic of China

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