Separation of Olefins and Paraffins Using Stable Customized Amorphous Fluoropolymer (CAF) Membranes

The oil and gas industry expends 250 trillion BTU/year separating olefins and paraffins (e.g., propylene from propane) through the use of costly and energy intensive distillation columns, a technology that is little changed in the last 40 years. The separations of these materials are some of the costliest, most energy intensive, and most technically difficult separations in the industry due to the very similar size and nature of the molecules being separated. The ability to separate these materials using a stable membrane would provide substantial economic benefit to petrochemical processes and dramatically decrease the energy required.

Using customized amorphous fluoropolymer (CAF), Compact Membrane Systems has developed membranes which have shown high propylene flux and propylene/propane selectivity over a period of greater than 180 days. The permeance and selectivity combination of the membranes are above the industry Robeson curve. While we have previously shown data for propylene/propane separation, we have recently demonstrated the ability to separate C2s (as well as C3s) obtaining very high olefin permeance (~270 GPU) and selectivity (>70) for ethylene/ethane separation. In addition, membrane stability was evaluated in presence of poisons such as hydrogen sulfide, acetylene and hydrogen. We will discuss these results as well as some of our economic modeling showing very low payback times and positive IRRs for a variety of scenarios governing petrochemical processes.