Ignition dynamics in glycolaldehyde flame catalyzed by Na and Mg ions: a theoretical multiscale approach

The effects of inorganic components on biofuel combustion characteristics are crucial for the design of green energy sources but are not fully understood. To address this knowledge gap, we herein investigate the catalytic effects of Na⁺ and Mg²⁺ on glycolaldehyde combustion and quantitatively predicts energy transfer within the molecular chain during fuel cracking and ionic bonding–derived catalytic behavior. From a molecular level thermodynamics, Na⁺ and Mg²⁺ reduce the activation energy of GA combustion by 5.3 and 22.8 kJ mol⁻¹, respectively. Moreover, Na⁺ is shown to enhance flame–vortex interactions at the flame front and thus reduce the spatial scale of the vortex from 532 to 286 m⁻¹, with the electromechanical perturbations induced by this ion lowering the activation energies of radical-producing vibrational fuel-cracking reactions. Radical fragments increase proton emission by 1.4 times, facilitating the release of turbulent kinetic energy within the flame, i.e., Na⁺ reduces the flame temperature by 68 K. The energy released at the flame front promotes the hydrodynamic mixing of the oxidant and fuel and thus facilitates complete combustion. By contrast, Mg²⁺ promotes not only fuel cracking but also extinguishant production, thus counteracting flame initiation.