Storage period prediction and metal compatibility of endothermic hydrocarbon fuels

Abstract

Storage period is an important storage-stability index of endothermic hydrocarbon fuels. In this work, the accelerated oxidation method was used to predict the storage period of fuels at room temperature. The amount limit of hydroperoxide number (8 ppm) is the criterion for judging the fuel deterioration. Therefore, the relationship between heating time corresponding with 8 ppm of hydroperoxide number vs. temperature was established, predicting that the lab-made No. 1 endothermic hydrocarbon fuel (EHF-1, with 25 ppm butylated hydroxytoluene (BHT)) can be stored up to 18.8 years under sealed storage at 20 °C. During storage, the BHT amount will decrease gradually with that of hydroperoxide number increased, and 8 ppm of hydroperoxide number is corresponding to the residual 10.6 ppm of BHT, which can also be used to investigate storage period of EHF-1. During storage, metals often exposed to fuels can affect the storage stability of fuels to varying degrees, hence metal compatibility is an important basis for the selection of metal materials for fuel facilities. Metal compatibility with EHF-1 was tested in terms of corrosion degree of metals, the amount of metallic dissolution, hydroperoxide number, total acid number, etc. The tested metals can promote the oxidation of EHF-1, and the order of metals to accelerate oxidation of EHF-l is red copper > DT4 iron > 321 stainless steel > 5052 aluminum alloys.