Inhibition ability of ionic liquid [Bmim][NO3], [Bmim][BF4], and [Emim][BF4] on spontaneous coal combustion

From TG result, [Bmim][BF4] has the best inhibition ability of spontaneous coal combustion to delay the initial temperature, maximum temperature, and final temperature of mass loss with oxidation process on lignite and long flame coal. Cation of ionic liquid (IL) is the critical factor of the oxidation reaction on lignite, and [Bmim](+) can destroy the structure of long flame coal. According to FTIR results, ILs can effectively decrease the easily oxidized functional group on lignite, and the removed ability is [Bmim][BF4] > [Emim][BF4] > [Bmim][NO3]. [Emim][BF4] has the best performance of removed ability on long flame coal. ILs as a green inhibitor and new way is applied to prevent fire in coal industries.