![]() So, the researchers tweaked the structure of the solvent, creating a molecule called 2-EEMPA. A collaboration with a team led by Robert Perry, a chemist at GE Global Research, revealed that when the amines bound CO 2, hydrogen atoms on solvent molecules became attracted to neighboring molecules, tying them together. Heldebrant's team found that when the solvent captured CO 2, carbon-rich solids precipitated out, making the liquid viscous and difficult to pump. Organic solvents can release CO 2 when heated but, unlike water, need not be boiled and recondensed, potentially saving energy. Over the next decade, he and his team created a collection of liquid organic solvents, eventually settling on one containing C0 2-grabbing amine groups with no need for water or dissolved capture agents. In 2009, David Heldebrant, a chemist at the Pacific Northwest National Laboratory (PNNL), sought a new approach: "The goal was to get away from the water," he says. MICHAEL PERKINS/PACIFIC NORTHWEST NATIONAL LABORATORY, ADAPTED BY N. All CO2 capture agents must be purified so they can be reused, but unlike water-based agents, organic solvents don't need to be boiled to release the CO2. A cheaper cleanup Organic solvents promise to capture carbon dioxide (CO2) from fossil fuel-burning power plants more cheaply than the water-based capture systems of today. The condensed water is added back to the amines and piped to the tower for another round of CO 2 capture. Then, applied pressure causes water vapor to condense, leaving a pure stream of CO 2 to be captured and stored. ![]() At the bottom of the tower, the CO 2-rich liquid gets pumped into a separate vessel and heated to boil off the water. As the droplets fall through the gas, they sop up CO 2. ![]() Typically, water that contains amines is sprayed into the top of an exhaust tower. ![]() Department of Energy projects that by 2035, the cost needs to fall from roughly $58 per ton with state-of-the-art water-based amines to $30 per ton. For carbon capture efforts to be scaled up by orders of magnitude, the U.S. Last year, companies captured some 40 million tons of CO 2 emissions, and the additional 30 carbon capture facilities planned worldwide could up that figure to 140 million tons-still minuscule compared with current annual global emissions of some 35 billion tons. "This is a beautiful, very complete study," Brennecke says.įor decades, researchers have worked to find ways to capture carbon from industrial emissions and either use it to make chemicals or store it underground. Enter new "water lean" capture materials, including one described in the latest report. Releasing the CO 2 requires boiling the water and later recondensing the water vapor, which requires a vast amount of energy and increases the cost. The problem is that once the amines capture CO 2, the greenhouse gas must be stripped off and stored so the amines can be reused. Today's technology uses CO 2-grabbing chemicals called amines, dissolved in water. tax credits are added to the mix, carbon capture is nearing commercial viability, says Joan Brennecke, a carbon capture expert at the University of Texas, Austin. But researchers are now developing a new generation of chemical CO 2 traps, including one shown this month to reduce the cost by nearly 20%. Today's most popular approach for capturing CO 2 is too expensive for widespread use. climate experts say, will also require capturing carbon dioxide (CO 2) from the tens of thousands of fossil fuel power plants and industrial smokestacks likely to keep belching for years to come. Windmills and solar panels are proliferating fast, but not fast enough to stave off the worst of climate change.
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