Energy Efficient Separations of Olefins and Paraffins through a membrane

Executive Summary

Throughout the petrochemical and refining industry, the separation of olefins and paraffins is generally performed via distillation, a costly and capital intensive method, particularly for light olefins. This project uses a silver-incorporated custom amorphous fluoropolymer membrane to separate olefins and paraffins. Compared to previous attempts using facilitated transport membranes, this membrane has been shown to have very good longevity in laboratory settings and has been tested with reasonably-expected process poisons. The objective of this project is to gain a better understanding of the membrane performance in realistic operating conditions through both real world testing and fundamental modelling of the membrane system. It targets the case of integrating a membrane module in a process to recover propylene from propane in a polymerization reactor purge stream, with the propylene recycled to the reactor.

Technical Challenge

Developing membranes with sufficient performance and ability to operate over long time periods in a real world environment

Potential Impact

The commercial benefit of a technology to separate olefins and paraffins through a membrane is potentially very large. Light olefins are one of the most important chemical markets globally, approaching 200 million metric tons of propylene and ethylene production in 2018. These molecules are extremely important due to their status as building blocks for numerous petrochemicals including polyethylene and polypropylene. Currently, these molecules are separated from each other using distillation, an energy-intensive process that is estimated to consume 0.3% of the world’s energy. While many of the early applications will take place in cooperation with distillation, as the membrane technology developing under this project becomes more accepted and proven it may come in direct competition with distillation for new builds.

Resources

Compact Membrane Systems brings extensive experience in olefin-paraffin gas separations technology, and application analysis for various membrane uses. The Dow team has experience in olefins production and brings a wide breadth of knowledge of system design, testing and use. The University of Minnesota is an expert in membrane separations and has experience in development, testing, modeling, optimization of membranes and membrane processes for hydrocarbon separations and other applications. ACS GCI Chemical Manufacturers Roundtable brings experience in improving the environmental performance of chemical processes.