Impacts of hydrogen to carbon ratio (H/C) on fundamental properties and supercritical cracking performance of hydrocarbon fuels

The precise investigations on modeling properties and performance of practical fuels are usually complicated because of the multi-component nature. On the basis of hydrogen to carbon ratio (H/C), as a simple and overall characterization parameter for hydrocarbon fuels, this work provides a comprehensive insight into the study of kerosene-based hydrocarbon fuels (H/C = 1.6-2.3). The fundamental properties and supercritical cracking performance of hydrocarbon fuels are influenced intrinsically by their H/C values and molecular weights (M) due to the compositional and structural effects. Thus, a new combined parameter, (H/C)/M-a, is proposed to model the performance of hydrocarbon fuels. It is found that the hydrocarbon fuel with a higher H/C has a higher net heating value, and that with a higher (H/C)/M-0.1 has a lower density. The viscosity decreases with the increase of (H/C)/M-0.5. The flash point shows a decreasing trend against the increase of (H/C)/M-2. The densities, viscosities and net heating values of 23 hydrocarbon fuels are calculated by means of the regression equations with the H/C and M data, and they are in agreement with the corresponding experimental values with the relative errors less than 2.5%, 10% and 1.5%, respectively. As investigated in an electrically heated tube reactor, the hydrocarbon fuel with a higher H/C performs thermal cracking more easily, absorb more heat and form fewer cokes. As a result, the cracking performance of hydrocarbon fuels can be predicted reasonably to a certain extent on the basis of H/C values. (C) 2015 Elsevier B.V. All rights reserved.