(423d) Simultaneous Capture of Carbon Dioxide and Mercury From Coal Flue Gas by Using Supported Ionic Liquid Solid Sorbents

Previous studies have shown that novel solid sorbents developed by the investigators can capture gas-phase mercury and carbon dioxide individually. These sorbents consist of ionic liquids supported on mesoporous silica particles with high surface area and pore volume. This work has been extended to demonstrate combined capture of mercury and carbon dioxide. In the combined capture process, mercury (present in trace quantities in flue gas) accumulates in the sorbent via strong chemical bonding over an extended time, while carbon dioxide (present in large quantities in flue gas) is reversibly adsorbed and desorbed.

Another key issue associated with carbon dioxide adsorption, the energy required for sorbent regeneration, is also addressed. To better understand the energy cost associated with carbon dioxide sorbent regeneration, the heats of adsorption and desorption were measured directly using microcalorimetery; the results were also fit with a thermodynamic model. These results provide guidelines for process design and operation cost estimation.