Efficacy of initiators on fuel conversion, heat sink, and coke propensity of hydrocarbon fuel under supercritical environment

Abstract

The investigation includes the cracking characteristics of a multi-component hydrocarbon fuel with a boiling range of 149–224 °C under supercritical environments. The impact of reactor pressure and the influence of initiators on cracking characteristics, such as fuel conversion, coke deposition, gas and liquid product distribution pattern, and heat sink capacities, of the fuel are examined explicitly. The fuel conversion improved by 70.8% as the reactor pressure increased from 2.5 MPa to 5.5 MPa at 650 °C. However, the coke deposition also increased by 55% for the corresponding pressure range. A decrease in the olefin-to-alkane ratio with pressure signifies the possibility of a reduction in unimolecular decomposition reactions and an increase in bimolecular reactions. The efficacy of two initiators, namely triethylamine (TEA) and di-tert-butyl peroxide (DTBP), on heat sinks and coke deposition was also examined. Between the two initiators, the nitrogen-based TEA initiator showed better performance in terms of fuel conversion and coke deposition rate, and the oxygen-based DTBP offered better heat sink capacity. About 22% increment in endothermicity was obtained with 1 wt% DTBP loading at 650 °C under 5.5 MPa pressure.