A modified plastic material greatly improves the ability to separate global warming-linked carbon dioxide from natural gas as the gas is prepared for use, according to engineers at The University of Texas at Austin who have analyzed the new plastics performance.
Like a sponge that only soaks up certain chemicals, the new plastic permits carbon dioxide or other small molecules to go through hour-glass shaped pores within it, while impeding natural gas (methane) movement through these same pores. The thermally rearranged (TR) plastic works four times better than conventional membranes at separating out carbon dioxide through pores.
Dr. Ho Bum Park, a postdoctoral student in the laboratory of Professor Benny Freeman, also found that TR plastic membranes act quicker. They permit carbon dioxide to move through them a few hundred times faster than conventional membranes do even as they prohibit natural gas and most other substances from traveling through their pores for separation purposes.
If this material was used instead of conventional cellulose acetate membranes, processing plants would require 500 times less space to process natural gas for use because of the membranes more efficient separation capabilities, and would lose less natural gas in their waste products, said Freeman, noting that, pound for pound, natural gas has a worse global warming impact on the atmosphere than carbon dioxide.
When developed for commercial use, the plastic could also be used to isolate natural gas from decomposing garbage, the focus of several experimental projects nationally. The TR plastic described in tomorrows issue of Science could also help recapture carbon dioxide being pumped into oil reservoirs in West Texas and elsewhere, where it serves as a tool for removing residual oil.
Freeman is a co-author on the Science article about the research. He holds the Kenneth A. Kobe Professorship and Paul D. and Betty Robertson Meek & Ame
|Contact: Barbra Rodriguez|
University of Texas at Austin