Inhibition effect of imidazolium-based ionic liquids on pyrophorisity of FeS

Abstract

To explore the inhibition of imidazolium-based ionic liquids on the pyrophorisity of sulfur corrosion products in oil tanks, FeS, the main component of sulfur corrosion products, was used as experimental samples in this paper. Four ionic liquids, [BMIM][I], [BMIM][BF4], [EMIM][BF4] and [BMIM][NO3], were selected to process the samples. The microstructure of the samples was characterized by a scanning electron microscope. The processes of spontaneous combustion and the changes of specific heat capacity of the sample were analyzed by TG-DSC. On this basis, the apparent activation energy, pre-exponential factor, and reaction mechanism function of the samples in the process of spontaneous combustion were obtained by the Kissinger method and the Malek method. The results show that the reaction process of the samples can be divided into four stages, and the third stage is the spontaneous combustion stage, in which the samples have a violent oxidation reaction and release a lot of heat. The ionic liquids have different degrees of inhibition effect on the pyrophorisity of FeS, among which [BMIM][I] have the most obvious inhibition effect, and the exothermic peak of the treated samples 25.7% lower than that of the untreated samples. The average activation energy of the samples treated with the four ionic liquids respectively increased by 65.28, 25.62, 35.27, and 33.88 kJ/mol, and the activation energy of the samples treated with ionic liquid [BMIM][I] showed the greatest overall improvement and the best inhibition effect.