Strategic Vapor Suppressing Additives for Ammonia Based CO2 Capture Solvent

CO2 is among the primary greenhouse gases in thr earth's atmosphere. This capture and sequestration of CO2 from process streams is of great importance to minimize greenhouse gas emissions from fossil fuels. The post combustion capture process consists of two steps, CO2 capturing by chemical absorption and solvent regeneration. The CO2 is subsequently stored in geological or other reservoirs. Aqueous ammonia can be used as absorbent for CO2. Ammonia is a low cost chemical in widespread commercial use and has the potential advantage of being free of degradation to hazardous molecules. Above all ammonia requires up to 40% lower regeneration energies compared to organic amines. The major concern using ammonia as capturing solvent is its high volatility. A possible approach to lower ammonia partial pressure is the elevation of the ammonia boiling temperature by additives is presented in this study. Selected inorganic salts were studied as vapour suppressing additives for aqueous ammonia.