2-Ethylhexyl nitrate (2-EHN), an important additive to diesel fuel, is produced from the nitration of iso-octanol with HNO3-H2SO4 mixed acid. In this study, the differential scanning calorimeter (DSC), accelerating rate calorimeter (ARC) and reaction calorimeter were used to analyze the thermal stability of 2-EHN and the thermal hazard of iso-octanol nitration. Four samples with different ratios of 2-EHN to mixed acid were tested using DSC. The results indicated that more mixed acid could catalyze the decomposition of 2-EHN. Three samples were tested using ARC and the results showed that sample 4 contained the lowest onset temperatures, T-D8 and T-D24. This shows that there is a higher probability of triggering the decomposition of the product 2-EHN from the iso-octanol nitration process. This conclusion was verified using RC1e tests at different temperatures. The RC1e experiments also indicated that the overall heat generation of these reactions was considerably large despite the high yields of the nitration process at 45 degrees C and 55 degrees C. This heat generation makes these semi-batch processes difficult to control, especially on a pilot or plant scale. Based on the maximum temperature of the synthesis reaction (MTSR) corrected by the yield, the only acceptable semi-batch process is the nitration reaction at 10 degrees C. (c) 2012 Elsevier Ltd. All rights reserved.