(125f) High Throughput Membrane Screening System Development for Carbon Capture Membranes

Carbon capture may be required for combustion based power plants in the near future. Current technology cannot capture carbon dioxide without unacceptable increases in the cost of energy. Membranes are an attractive option for separation of carbon dioxide from pre- and post-combustion gas streams. Polymer membranes, supported ionic liquid membranes (SILM), and mixed matrix membranes (MMM) are all potential candidate technologies. Each of these types of membranes has several ‘knobs’ which can be turned to control the separation properties of the membrane such as variation of the types of polymer, ionic liquid, or filler particle. While there are currently a limited number of commercially available polymers that show promise for carbon capture, synthesis of designer polymers is possible, greatly increasing the number of potential polymer membranes for study. Supported ionic liquid membranes consist of an ionic liquid embedded in a polymer support and are designed to have the separation characteristics of the ionic liquid. With an estimated 10¹⁴ ionic liquid theoretically possible, there is essentially a limitless number of SILMs from which to select. MMMs are a type of membrane consisting of a polymer matrix with embedded filler particles. In principle, a MMM can have the separation characteristics of the filler particle. For MMMs, the polymer matrix, filler particle identity, particle size, and particle loading can all be varied. Even if we limit ourselves to metal organic frameworks, which have shown promise for CO₂ capture, the number of possible MMMs is essentially limitless. Due to the nearly infinite number of potential membranes for CO₂ separation, a high throughput testing system for rapid screening of candidate membranes is required. To meet this need, a system capable of testing 16 membranes simultaneously has been developed at NETL. The system operates in the isobaric mode, which allows for a constant pressure drop across the membrane, and can test mixed gas performance. The system is designed to allow rapid screening of membrane candidates for CO₂ separation under realistic temperature and pressure conditions for pre- and post-combustion separation. The design of this novel system will be presented, and key technical issues will be discussed.