Electricity generation from fossil fuel combustion is a major source of CO₂ emissions both internationally (37% of total emissions)[1] and nationally (50% of total emissions)[2]. To effectively reduce atmospheric CO₂ emissions in the short to medium term will probably require CO2 capture and storage as a part of the solution.
The CSIRO Division of Energy Technology has undertaken a major CO₂ capture research program covering many aspects of the technology. On the laboratory scale, the chemical reactions involved in CO₂ capture and release by chemical absorption are being investigated and modelled to identify where and how improvements in efficiency can be made. In this work a detailed characterisation of five amine formulations has been undertaken. The vapour-liquid equilibria (VLE) between 5 molL^-1 solutions and CO₂ has been determined at 40°C and 100°C for CO₂ partial pressures covering a the range 2 - 900 kPa and compared to monoethanolamine (MEA). MEA is used in CO₂ cleaning of gas in commercial processes. The partial pressure range and temperature difference was chosen to provide data relevant PCC from power stations and other industries such as steel manufacturing and to give an indication of the lean and rich loadings of the formulations.
Results showed that some formulations have similar or higher absorption capacities than MEA. Many of the amine formulations were found to have a higher cyclic capacity than MEA. These results highlight the importance and need to collect CO₂ absorption data in aqueous amines at a range of CO₂ partial pressures.