Abstract
Ammonia solutions are considered to be effective solvents for carbon dioxide absorption. Despite numerous advantages of these solvents, their high volatility is a significant technical and economic problem. Therefore, in this work, silica particles were used as additives to improve CO 2 absorption and inhibit NH 3 desorption. SiO 2 microparticles and colloidal SiO 2 particles in the concentration range of 0-0.15 wt.% were used in this study. The most favorable mass transport for CO2 absorption was at the concentration of colloidal particles of 0.05 wt.%. Under these conditions, the enhancement in the number of moles of absorbed CO 2 was above 30%. However, in solvents containing 0.01 wt.% SiO2 microparticles, the increase in CO 2 absorption was about 20%. At the same time, the addition of SiO2 particles significantly reduced the escape of ammonia from the solution. The best improvement was obtained when colloidal SiO 2 particles were added, and then NH 3 escape was decreased by about 60%. This unfavorable phenomenon was also inhibited in ammonia solutions containing SiO2 microparticles at a concentration of 0.01 wt.%.
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