(440c) Supported Ionic Liquid Sorbent for Simultaneous Capture of Carbon Dioxide and Mercury

Carbon dioxide and mercury vapor in the atmosphere are both significant environmental concerns in the US. Capture of carbon dioxide and mercury at their major sources, coal fired power plants, requires multiple air pollution control devices if conventional technologies are used. To reduce the cost of controlling these emissions, a new approach is being developed in which both carbon dioxide and mercury are captured using an integrated adsorbent system. In this adsorbent system, an ionic liquid is supported on mesoporous silica particles with high surface area and pore volume. Through proper choice of ionic liquid chemistry, carbon dioxide is captured reversibly, while mercury is captured irreversibly. Since carbon dioxide is sorbed reversibly, the sorbent can be used in a conventional carbon dioxide sorption/desorption process. On the other hand, mercury, which is present in very small quantities, accumulates in the sorbent over an extended time. Test results indicate that this system can be used to capture carbon dioxide and mercury simultaneously from simulated flue gas.