I wonder how tall sugar cane can grow in microgravity. It seems the way this would work as a liquid propellant is keeping the sugar in an aqeous solution not higher than 67.5% and suspending solid potassium nitrate particles in it, making it a monopropellant. Not ideal, not just because of the water which won't participate in the reaction, but also because one would have to work out the ratios to define the compounds and reactions (that's a troubling proposition for myself at least). Here's molten potassium nitrate though, and an associated product. From here reactions with any existing hydrogen-containing fuels can be made easily enough; after reading that it is soluble in ammonia I tested it with that first and was greeted by chlorine-hydrogen levels of exhaust velocity.
Material Potassium Nitrate Elements K N O ElementCount 1 1 3 Density_kg__m3 2109 EnthalpyOfFormation_kJ__mol -494 MeltingPoint_K 607 BoilingPoint_K 673 ThermalConductivity_W__m_K .411 SpecificHeat_J__kg_K 940.2 Viscosity_Pa_s 1.01e-3 Dissociation Products Potassium Monatomic Nitrogen Monatomic Oxygen ProductCounts 1 1 1
Material Potassium Hydroxide Elements K O H ElementCount 1 1 1 Density_kg__m3 2120 EnthalpyOfFormation_kJ__mol -425.8 GibbsFreeEnergyOfFormation_kJ__mol -380.2 BondDissociationEnergy_kJ__mol 667 MeltingPoint_K 633 BoilingPoint_K 1600 SpecificHeat_J__kg_K 851.8 Test reactions: