Stability and combustion performance enhancement of ethanol/kerosene fuel by carbonized poly[cyclotriphosphazene-co-(4,4′-sulfonyldiphenol)] nanotubes via biomimetic hydrogen bonding strategy

Abstract

Sustainable aviation fuels (SAF) are a major research focus in the refining and aerospace industries. However, the liquid-phase separation and low-temperature starting performance of ethanol-based fuels are a difficult problem for SAF development. In this study, a biomimetic hydrogen bond strategy, inspired by the DNA structure, was used to stably disperse an ethanol kerosene-based nanofluid fuel. Carbonized poly [cyclotriphosphazene-co-(4,4′-sulfonyldiphenol)] (CPZS) nanoparticles (containing hydrogen bond acceptor) were synthesized to improve the dispersion and sedimentation and inhibit absorption of water by the fuel, allowing the proportion of ethanol to be increased to 50 wt%. This fuel had an unprecedented shelf-life of 140 days (representing an extension of 560%). The hydrogen bonding between CPZS and the ethanol/kerosene hybrid fuel was verified. The CPZS and ethanol/kerosene hybrid fuel exhibited excellent stability and dramatically enhanced the ignition performance, with the ignition delay time declining to 243 ms at an ambient temperature of 975 °C (821.0 ms for E50/K50). Compared with pure kerosene fuel, the CO2 emissions of the E50/K50 hybrid fuel combustion decreased by 19.13%. This study provides a new biomimetic strategy based on hydrogen bonding for preparing ethanol-based fuel with a long shelf-life, enabling the possibility of directly using biomass ethanol in SAF.