Zhan J, Wang HH, Song SN, Hu YA, Li JA (2011) Role of an additive in retarding coal oxidation at moderate temperatures. Proceedings of the Combustion Institute 33, 2515-2522. [In English]

Web link: http://dx.doi.org/10.1016/j.proci.2010.06.046

Keywords:

Coal, Oxidation at moderate temperatures, Retarding additives, Control, of self-heating phenomena, infrared-spectroscopy, inorganic matter, bituminous coal, ft-ir, chemistry, mechanism, inherent, xps

Abstract: The impact of an additive on coal oxidation process is studied from the mechanistic perspective, aiming at development of a guideline in search of effective inhibitors for controlling the coal self-heating phenomena. The salt Na(3)PO(4) was chosen as an additive. Behaviors of samples with/without the additive were examined at temperatures up to 400 degrees C both in oxidative and inert atmosphere using a TGA instrument, and the compounds on coal surface during oxidation and pyrolysis were monitored by FT-IR technique. The TGA data show that the impact of the additive on coal oxidation process can be directly evaluated using a parameter defined as the percentage of mass increase at similar to 265 degrees C, and the addition of Na(3)PO(4) slows down the rates of oxygen uptake and decomposition reactions. FT-IR results also indicate that the additive suppresses both the coal oxidation and pyrolysis processes essentially by accelerating the formation of saturated ether linkages. Further analysis suggests that Na(3)PO(4) plays a role in modifying the routes for decomposition of hydroxyl, and subsequently improving the coal thermal stability. (C) 2010 The Combustion Institute. Published by Elsevier Inc. All rights reserved.