Creating a Captivating Cage for Carbon

May 11, 2010
A tough, hard-working particle known as ZIF-8 that can selectively remove carbon dioxide from a complex mixture of gases was designed by scientists at Pacific Northwest National Laboratory.

(PhysOrg.com) -- A tough, hard-working particle known as ZIF-8 that can selectively remove carbon dioxide from a complex mixture of gases was designed by scientists at Pacific Northwest National Laboratory. Similar materials available today are very delicate, unable to tolerate exposure to water and air. The hexagonal crystals are far from delicate, but the crystals were designed using a straightforward approach that relies on three readily available chemicals.

Natural gas often contains and other impurities that reduce the effectiveness of this common fuel. Industries need a material to remove the carbon dioxide. The ideal material is affordable, selective, removes large amounts of carbon dioxide, and can be recharged. A rechargeable material traps its target and then releases it under specific circumstances. Rechargeable materials can be used repeatedly, reducing costs and waste. Nano ZIF-8 might prove to be the answer.

Working with the chemicals at about 100 degrees centigrade, the temperature at which water boils, the researchers melted off-the-shelf zinc nitrate and 2-methyl imidazole with a third chemical known as a surfactant, which helped the chemicals to mix to form hexagonal shaped . They washed out the impurities and dried the crystals. The surfactant in the mixture caused the chemicals to assemble into nanoscale ZIF-8, a white powder resembling baking flour.

Next, the team did extensive experiments on the particles with transmission electron microscopes, scanning electron microscopes, and at the Department of Energy's EMSL. They found that the crystals had a diameter of about 50 with a wall thickness of about 40 nanometers and very high surface area. "A gram of this stuff has the area of a football field," said Dr. Praveen Thallapally, a materials scientist at PNNL and co-lead on this research with Dr. Jun Liu and Dr. Greg Exarhos.

Funded by DOE's Office of Basic Energy Sciences, the team will be conducting research to increase the surface area of the material. While the material has a high surface area, it is about a factor of 3 lower than the more common material available today. "We want to increase that surface area, to really push the envelope," said Exarhos.

Explore further: Scientist hopes to improve rare earth purification process

More information: Nune SK, PK Thallapally, A Dohnalkova, C Wang, J Liu, and GJ Exarhos. 2010. "Synthesis and Properties of Nano Zeolitic Imidazolate Frameworks." Chemical Communications. DOI:10.1039/c002088e

Related Stories

Miniature Gas Tank

Jan 28, 2005

Porous networks of organic Van der Waals crystals can selectively store methane and carbon dioxide Washing powders are generally known to consist partially of inorganic zeolites. These aluminosilicates form porous structure ...

Crystal sponges excel at sopping up CO2

Dec 01, 2005

Since the Industrial Revolution, levels of carbon dioxide---a major contributor to the greenhouse effect---have been on the rise, prompting scientists to search for ways of counteracting the trend. One of the main strategies ...

Serpentine locks up Carbon Dioxide

Sep 02, 2004

A common mineral can remove carbon dioxide from combustion gases, but in its natural state, it is glacially slow. Now, a team of Penn State researchers is changing serpentine so that it sequesters the carbon ...

New Class of Catalyst Sports Shapely Selectivity

Mar 10, 2010

A new class of catalytic material has been studied by scientists at Pacific Northwest National Laboratory. Metal-organic frameworks (MOFs) display a unique three-dimensional structure that is highly selective ...

Recommended for you

Chemists eye improved thin films with metal substitution

Jul 21, 2014

The yield so far is small, but chemists at the University of Oregon have developed a low-energy, solution-based mineral substitution process to make a precursor to transparent thin films that could find use ...

User comments : 1

Adjust slider to filter visible comments by rank

Display comments: newest first

YSLGuru
1 / 5 (1) May 12, 2010
This is great news! Now we just need to find a way to get rid of that deadly and environmnetally dangerous brother of CO2, Oxygen! If we can find a way to eliminatre Oxygen too we will have finally created our Pro enviro-friendly haven on earth. Granted no one will be able to live to see it since we need oxygen to breathe and the trees need co2 to create the Oxygen we need but that's not whats important.