Experimental Study on the Reaction of Magnesium in Carbon Dioxide and Nitrogen Atmosphere

This manuscript presents an experimental study focusing on the combustion of magnesium in an atmosphere depleted of oxygen. The study explores various mixtures of carbon dioxide and nitrogen, examining their impact on the combustion performance. The experimental design involved evaluating how the carbon content influences combustion parameters. Temperature profiles were analyzed to elucidate different stages of the combustion process. Furthermore, the effects of pressure (2 and 3 ata) and the composition of CO2-N2 mixtures (10%, 19.5%, 35%, 48%, 72%, and 80% CO2 content) on magnesium combustion, including ignition time, maximum temperature, and post-combustion temperatures, were investigated. The results revealed a substantial impact on the ignition delay and combustion time, with the ignition delay decreasing with higher chamber pressure. The combustion process, especially with regard to the ignition time and heat of combustion, was notably affected by CO2 concentration. The morphology of the combustion residue from the magnesium microparticles was characterized using scanning electron microscopy combined with energy-dispersive X-ray spectroscopy (SEM-EDX). The reaction of Mg with CO2 represents a promising energy source, quickly releasing a substantial amount of heat with a very low quantity of Mg. The estimated value of the heat of combustion for magnesium in N2-CO2 atmosphere is 78.4 kJ mol−1.