Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Computer Simulations Indicate Calcium Carbonate Has a Dense Liquid Phase

23.08.2013
Berkeley Lab research could help scientists predict how carbon is stored underground

Computer simulations conducted at the U.S. Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) could help scientists make sense of a recently observed and puzzling wrinkle in one of nature’s most important chemical processes.


Artistic rendition of liquid-liquid separation in a supersaturated calcium carbonate solution. New research suggests that a dense liquid phase (shown in red in the background and in full atomistic detail based on computer simulations in the foreground) forms at the onset of calcium carbonate crystallization. (Credit: Berkeley Lab)

It turns out that calcium carbonate—the ubiquitous compound that is a major component of seashells, limestone, concrete, antacids and myriad other naturally and industrially produced substances—may momentarily exist in liquid form as it crystallizes from solution.

Calcium carbonate is a huge player in the planet’s carbon cycle, so any new insight into how it behaves is potentially big news. The prediction of a dense liquid phase during the conversion of calcium carbonate to a solid could help scientists understand the response of marine organisms to changes in seawater chemistry due to rising atmospheric CO2 levels. It could also help them predict the extent to which geological formations can act as carbon storage reservoirs, among other examples.

The research is published in the August 23 issue of the journal Science. It was performed in support of the Center for Nanoscale Control of Geologic CO2, an Energy Frontier Research Center established at Berkeley Lab by the U.S. Department of Energy.

The research may also reconcile some confounding experimental observations. For more than a century, scientists believed that crystals nucleate from solution by overcoming an energy barrier. But recent studies of calcium carbonate revealed the presence of nanoscopic clusters which, under certain conditions, appear to circumvent the barrier by following an alternative aggregation-based crystallization pathway.

“Because nucleation is ubiquitous in both natural and synthetic systems, those findings have forced diverse scientific communities to reevaluate their longstanding view of this process,” says the study’s co-corresponding author Jim De Yoreo, formerly of Berkeley Lab and now a scientist at Pacific Northwest National Laboratory.

The Berkeley Lab-led team used molecular dynamics simulations to study the onset of calcium carbonate formation. The simulations predict that in sufficiently supersaturated calcium carbonate solutions, nanoscale dense liquid droplets can spontaneously form. These droplets then coalesce to form an amorphous solid prior to crystallization.

The findings support the aggregation-based mechanism of calcium carbonate formation. They also indicate that the presence of the nanoscale phase is consistent with a process called liquid-liquid separation, which is well known in alloys and polymers, but unexpected for salt solutions.

“Our simulations suggest the existence of a dense liquid form of calcium carbonate,” says co-corresponding author Adam Wallace. He conducted the research while a post-doctoral researcher in Berkeley Lab’s Earth Sciences Division, and is now an assistant professor in the Department of Geological Sciences at the University of Delaware.

“This is important because it is an as-yet unappreciated component of the carbon cycle,” adds Wallace. “It also provides a means of explaining the unusual presence of nanoscale clusters in solution within the context of established physical mechanisms.”

This research was supported by the U.S. Department of Energy’s Office of Science through the Energy Frontier Research Center program established in 2009. The work was conducted at Berkeley Lab’s Molecular Foundry, a Department of Energy national user facility. The research also used resources of the Department of Energy’s National Energy Research Scientific Computing Center, which is located at Berkeley Lab.

The Molecular Foundry is one of five DOE Nanoscale Science Research Centers (NSRCs), national user facilities for interdisciplinary research at the nanoscale, supported by the DOE Office of Science. Together the NSRCs comprise a suite of complementary facilities that provide researchers with state-of-the-art capabilities to fabricate, process, characterize and model nanoscale materials, and constitute the largest infrastructure investment of the National Nanotechnology Initiative. The NSRCs are located at DOE’s Argonne, Brookhaven, Lawrence Berkeley, Oak Ridge and Sandia and Los Alamos National Laboratories. For more information about the DOE NSRCs, please visit science.energy.gov.

Lawrence Berkeley National Laboratory addresses the world’s most urgent scientific challenges by advancing sustainable energy, protecting human health, creating new materials, and revealing the origin and fate of the universe. Founded in 1931, Berkeley Lab’s scientific expertise has been recognized with 13 Nobel prizes. The University of California manages Berkeley Lab for the U.S. Department of Energy’s Office of Science. For more, visit www.lbl.gov.

The DOE Office of Science is the single largest supporter of basic research in the physical sciences in the United States and is working to address some of the most pressing challenges of our time. For more information, please visit science.energy.gov.

Additional information:
• The research, “Microscopic Evidence for Liquid-Liquid Separation in Supersaturated CaCO3 Solutions” is published in the August 23, 2013 issue of the journal Science.

Dan Krotz | EurekAlert!
Further information:
http://www.lbl.gov

More articles from Life Sciences:

nachricht Symbiotic bacteria: from hitchhiker to beetle bodyguard
28.04.2017 | Johannes Gutenberg-Universität Mainz

nachricht Nose2Brain – Better Therapy for Multiple Sclerosis
28.04.2017 | Fraunhofer-Institut für Grenzflächen- und Bioverfahrenstechnik IGB

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Fighting drug resistant tuberculosis – InfectoGnostics meets MYCO-NET² partners in Peru

28.04.2017 | Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

 
Latest News

Wireless power can drive tiny electronic devices in the GI tract

28.04.2017 | Medical Engineering

Ice cave in Transylvania yields window into region's past

28.04.2017 | Earth Sciences

Nose2Brain – Better Therapy for Multiple Sclerosis

28.04.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>