Ionic Liquid Thin Film Technology – Advanced Materials for Gas Purification

Novel Supported Ionic Liquid Phase (SILP) materials consist of an ionic liquid, dispersed as a thin film on the inner surface of a highly porous solid material. Since the ionic liquid is dispersed on the inner surface of the support, a dry solid material is obtained. These materials can be handled like classical adsorbents and can be applied in established fixed-bed reactors, thus making these novel materials highly attractive for large scale applications.

Due to the extremely low vapor pressure of ionic liquids, SILP materials are especially suited for continuous gas-phase reactions since no leaching of ionic liquid can occur via the gas-phase.SILP materials have been applied in dedicated gas purification systems, making use of the ionic liquids’ tunable solubility for certain compounds in the gas stream. Latest results from gas-phase desulphurization studies in which the sulfur compound butyl-mercaptan is absorbed in the ionic liquid film of the SILP material indicate the high potential for industrial applications. Easy regeneration of the SILP material was achieved by pressure and temperature swing cycles. Additionally, N-containing compounds have been removed from feed gas, exemplifying the potential of SILP adsorbers for industrial, first responder and military gas filters.

It is anticipated that SILP technology will facilitate new and promising applications in gas-purification scenarios both for the removal of hazardous gas components from exhaust streams or for the purification of valuable gases in a highly energy efficient manner.