Scientists at Concordia University have developed a transparent gel fuel based on kerosene that could power future space rockets and satellites.
The new propellant combines the key advantages of liquid and solid fuels. It maintains a firm gel structure while resting in storage tanks, but turns into a free-flowing liquid when subjected to mechanical force or heat.
To create the fuel, researchers blended standard kerosene with lecithin, a natural organic substance, and a small quantity of calcium chloride. The added salt prompts the lecithin molecules to self-assemble into long, interconnected chains known as micelles. This microscopic network traps the kerosene within its structure, giving the mixture viscoelastic properties.
Fuel flow and temperature control
A defining characteristic of the gel is how dramatically it thins under physical pressure. When the shear rate increases from 1 to 100 reciprocal seconds, the viscosity of the material drops roughly a hundredfold. This thinning allows the propellant to travel through pumps and atomise cleanly through injector nozzles before combustion.
Heat provides an alternative method to regulate how the substance flows. Depending on the exact concentration of the thickening agent, the gel transitions into a liquid state at temperatures between 59 degrees Celsius and 68 degrees Celsius. The internal framework breaks down even faster if ethanol is introduced, which dissolves the micelle network and liquefies the gel almost immediately.
Propellant safety and testing limits
While resting in a reservoir, the gel behaves largely like an elastic solid. The developers intended this resting state to suppress fuel movement inside spacecraft tanks and reduce the risk of accidental leaks compared with traditional liquid propellants. Laboratory samples demonstrated durable shelf stability, remaining unchanged for more than a year inside sealed containers.
Concordia University is a public research institution located in Montreal, Canada. Kerosene has served as a foundational rocket propellant across the space industry for decades, typically refined into aerospace grades like RP-1. In traditional liquid systems, propellant sloshing can shift a rocket's centre of mass during flight, forcing engineers to install heavy internal baffles to maintain stability.
The research team published their findings in Langmuir, a scientific journal published by the American Chemical Society that focuses on the physical chemistry of interfaces and colloids. While the study tracked the breakdown of the micelle network under thermal shifts and mechanical loads, the scientists have not yet tested the fuel inside operational rocket engines or satellite thrusters, keeping their initial work focused on its physical and flow properties.
