Membranes on Mars

Membranes might help reduce carbon dioxide emissions from factory smoke stacks.

It could, for example, be used to filter air on the space station or on a spaceship bound for Mars. Carbon dioxide, which is a waste product of our metabolism, must continually be removed from the atmosphere of self-contained spacecraft. Membranes that are permeable only to carbon dioxide would be perfect, says Mason. "The CO₂ would just passively go through the membrane into a holding chamber - or out into space. Oxygen and other gases would stay intact inside the habitat."

These membranes could potentially help slow global greenhouse warming, too. "There's some thought," says Mason, "that a membrane could be used in extracting CO₂ from factory smoke stacks - reducing the amount of carbon dioxide that's dumped into the atmosphere." Such an application still lies in the future, he says.

"The biggest potential Earth-application," adds Way, "is the removal of CO₂ from natural gas. CO₂ is the most common contaminant in natural gas besides water vapour. Membrane separations are one of the primary processes used to filter natural gas so that it meets pipeline specifications of less than 2% CO₂." This is a big deal because "the natural gas industry is huge - more than 100 billion dollars per year in retail value," according to Way.

To Mason, "the most exciting part of this technology is the fact that it may leverage us to actually go to Mars and live and work there someday." And, in the meantime, there are plenty of uses for it right here on Earth.