(129d) Separation of Olefin-Paraffin Mixtures with OptipermTM Customized Amorphous Fluoropolymer Membranes

The separations of olefins from paraffins are some of the costliest, most energy intensive, and most technically difficult separations in the chemical industry due to the very similar size and nature of the molecules being separated. The technologies currently available for olefin-paraffin separation include distillation, adsorption, and absorption. Olefin-paraffin mixtures are conventionally separated mainly by distillation which is highly energy and capital intensive. A membrane based olefin-paraffin separation technology has the potential to provide substantial economic benefit to petrochemical industry and drastically reduce the energy required. While separations with membranes have been demonstrated in the laboratory, problems with membrane stability have prevented development of commercial systems.

Compact Membrane Systems (CMS) has developed Optiperm^TM membrane, a customized amorphous fluoropolymer (CAF) containing silver ions that selectively transport olefin molecules from a mixture of olefin and paraffin. Optiperm^TM membrane has shown stable performance over 12 months with high propylene flux and propylene/propane selectivity in the laboratory. Similar results were also obtained with ethylene and ethane gas mixtures. A broad range of tests have been conducted to characterize the membrane resistance to common poisons (such as hydrogen, acetylene, carbon dioxide) in refinery gas streams.

These silver based Optiperm^TM membranes have been tested in the laboratory with actual refinery gas mixture from a distillation column. A pilot Optiperm^TM system has been installed recently at the Delaware City Refining Company (DCRC) site in Delaware City, DE. The testing of the pilot unit has been initiated to provide real-world evidence of membrane stability in realistic conditions validating our laboratory testing. Pilot unit test results as well as some of our economic modeling results showing very low payback times and positive IRRs for a variety of scenarios governing petrochemical processes will be discussed in this presentation.