Nav: Home

New method for identifying carbon compounds derived from fossil fuels

September 13, 2017

Scientists at the National Institute of Standards and Technology (NIST) have developed a laboratory instrument that can measure how much of the carbon in many carbon-containing materials was derived from fossil fuels. This will open the way for new methods in the biofuels and bioplastics industries, in scientific research, and environmental monitoring. Among other things, it will allow scientists to measure how much of the carbon dioxide (CO2) in the atmosphere came from burning fossil fuels, and to estimate fossil fuel emissions in an area as small as a city or as large as a continent.

This is possible because carbon atoms occur in heavy and light forms, or isotopes, and measuring the relative amounts of each can reveal the source of the carbon. Using carbon isotopes in this way is not a new idea, but it requires extremely precise--and expensive--measurements. The new instrument, developed by NIST chemists Adam Fleisher and David Long and based on a technology called cavity ringdown spectroscopy (CRDS), promises to dramatically reduce the cost of those measurements. They described the instrument's performance in The Journal of Physical Chemistry Letters.

"Measuring carbon isotopes is an extremely useful technique, but until now, it has found limited use because of the cost," said Long. "Lowering the cost will open the way for new applications, especially ones that require testing a large number of samples."

The key to these measurements is carbon-14, a radioactive (yet harmless) isotope of carbon that is formed in the upper atmosphere. That carbon-14 finds its way into all living things. Unlike regular carbon, carbon-14 is unstable, with a half-life of 5,730 years. When living things die, they stop incorporating carbon into their bodies, and their carbon-14 starts to decay away.

Scientists can calculate how long ago something died by measuring how much carbon-14 is in its remains. That technique is called carbon dating, and scientists use it to date things like Neanderthal bones and ancient plant fibers.

Fossil fuels also are the remains of living things, mainly plants that died hundreds of millions of years ago. Virtually all their carbon-14 decayed away eons ago, so anything derived from them is marked by the absence of measurable amounts of carbon-14.

But carbon-14 is extremely rare, and to use it for identifying fossil fuels, scientists need to be able to measure it at concentrations as low as 1 part in 10 trillion. That's the equivalent of a single grain of sand in 60 dump trucks full of the stuff.

To measure concentrations that low, you need an extremely sensitive measurement technique, and such a technique already exists. Archaeologists have been relying on it for decades. But that technique requires a particle accelerator to separate the isotopes (the heavier carbon-14 accelerates more slowly than everyday carbon-12), along with a facility to house it and a team of PhDs to run it.

The CRDS instrument that Fleisher and Long have developed can sit on a laboratory benchtop and is relatively inexpensive to operate.

CRDS instruments analyze gases by detecting the wavelengths of light they absorb. For instance, CO2that contains carbon-14--so-called heavy CO2--absorbs a slightly different wavelength than regular CO2.

To measure how much heavy CO2 you have in a CO2 sample, you first inject the sample into the instrument's measurement cavity (the "C" in CRDS), which is a tube with mirrors inside at either end. You then tune a laser to the exact wavelength that only heavy CO2 absorbs and shoot a burst of it into the cavity. As the laser light bounces between the mirrors, some of its energy is absorbed by the gas. The greater the absorption, the greater the concentration of heavy CO2.

To achieve the required sensitivity, Fleisher and Long enhanced existing CRDS technology by engineering a system that chills the cavity to a uniform minus 55 degrees Celsius and minimizes temperature fluctuations that would throw off the measurement. Making the cavity very cold allows their instrument to detect very faint signals of light absorption, the same way that you might be able to hear a pin drop if you made a room extremely quiet.

This and other improvements boosted the instrument's sensitivity enough for accurate carbon dating.

To test biofuels and bioplastics, you would first burn those materials, then collect the resulting CO2 for analysis. This would allow you to test a fuel mixture to determine what fraction of it is biofuel. In the airline industry, for example, this would be useful because some countries require that aviation fuels include a specific biofuel percentage. Such tests could also be used to verify that bioplastics, which sell for a premium, do not contain petroleum-derived compounds.

To estimate fossil fuel emissions in a geographic area, you would collect many air samples across that area and analyze the atmospheric CO2 in those samples. Areas with high fossil fuel emissions, such as cities and industrial zones, will have below-normal concentrations of heavy CO2.

"Fossil fuel emissions dilute the concentration of heavy CO2 in the air," said Fleisher. "If we can accurately measure that concentration after it's been diluted, we can calculate how much fossil fuel emissions are in the mix."

A report from the National Academy of Sciences estimated that 10,000 samples a year, collected at carefully chosen locations around the United States, would be enough to estimate national fossil fuel emissions to within 10 percent of the actual value. Such a system of measurements can increase the reliability of national emissions estimates. This would be especially useful in parts of the world where high-quality emissions data are not readily available.
-end-
"There is a need for this type of measurement in many industries," Fleisher said. "We've demonstrated a path to meeting that need in a cost-effective way."

Paper: A. Fleisher, D. Long, Q. Liu, L. Gameson and J. Hodges. Optical Measurement of Radiocarbon below Unity Fraction Modern by Linear Absorption Spectroscopy. The Journal of Physical Chemistry Letters. Published online 7 September 2017. DOI: 10.1021/acs.jpclett.7b02105.

National Institute of Standards and Technology (NIST)

Related Carbon Articles:

The carbon dioxide loop
Marine biologists quantify the carbon consumption of bacterioplankton to better understand the ocean carbon cycle.
Transforming the carbon economy
A task force commissioned in 2016 by former US Secretary of Energy Ernest Moniz has proposed a framework for evaluating R&D on recycling carbon dioxide and removing large amounts of CO2 from the atmosphere.
Closing the carbon loop
Research at the University of Pittsburgh's Swanson School of Engineering focused on developing a new catalyst that would lead to large-scale implementation of capture and conversion of carbon dioxide (CO2) was recently published in the Royal Society of Chemistry journal Catalysis Science & Technology.
An overlooked source of carbon emissions
Nations that pledged to carry out the Paris climate agreement have moved forward to find practical ways to reduce greenhouse gas emissions, including efforts to ban hydrofluorocarbons and set stricter fuel-efficiency standards.
Enabling direct carbon capture
Researchers have developed a solid material that can capture carbon dioxide from the atmosphere, even at very low concentrations.
Development of a novel carbon nanomaterial 'pot'
A novel, pot-shaped, carbon nanomaterial developed by researchers from Kumamoto University, Japan is several times deeper than any hollow carbon nanostructure previously produced.
Unraveling truly one-dimensional carbon solids
Elemental carbon appears in many different forms, including diamond and graphite.
Carbon leads the way in clean energy
Groundbreaking research at Griffith University is leading the way in clean energy, with the use of carbon as a way to deliver energy using hydrogen.
Consumers care about carbon footprint
How much do consumers care about the carbon footprint of the products they buy?
Assessing carbon capture technology
Carbon capture and storage could be used to mitigate greenhouse gas emissions and thus ameliorate their impact on climate change.

Related Carbon Reading:

Altered Carbon (Takeshi Kovacs)
by Richard K. Morgan (Author)

SOON TO BE A BRAND-NEW SERIES ON NETFLIX

In the twenty-fifth century, humankind has spread throughout the galaxy, monitored by the watchful eye of the U.N. While divisions in race, religion, and class still exist, advances in technology have redefined life itself. Now, assuming one can afford the expensive procedure, a person’s consciousness can be stored in a cortical stack at the base of the brain and easily downloaded into a new body (or “sleeve”) making death nothing more than a minor blip on a screen.

Ex-U.N. envoy Takeshi Kovacs has been killed before, but... View Details


Carbon Democracy: Political Power in the Age of Oil
by Timothy Mitchell (Author)

Does oil wealth lead to political poverty? It often looks that way, but Carbon Democracy tells a more complex story. In this magisterial study, Timothy Mitchell rethinks the history of energy, bringing into his grasp as he does so environmental politics, the struggle for democracy, and the place of the Middle East in the modern world. 

With the rise of coal power, the producers who oversaw its production acquired the ability to shut down energy systems, a threat they used to build the first mass democracies. Oil offered the West an alternative, and with it came a new form of... View Details


Blood on the River: James Town, 1607
by Elisa Carbone (Author)

Twelve-year-old Samuel Collier is a lowly commoner on the streets of London. So when he becomes the page of Captain John Smith and boards the Susan Constant, bound for the New World, he can’t believe his good fortune. He’s heard that gold washes ashore with every tide. But beginning with the stormy journey and his first contact with the native people, he realizes that the New World is nothing like he imagined. The lush Virginia shore where they establish the colony of James Town is both beautiful and forbidding, and it’s hard to know who’s a friend or foe. As he learns the language of... View Details


Student Lab Notebook: 100 Spiral Bound duplicate pages(Package may vary)
by Hayden-McNeil Publishers (Author)

100 Carbonless duplicate pages sequentially numbered.
Copy (bottom page) perforated.
Fully laminated front and back cover.
Back cover folds over to prevent bleed through between sets.
Durable plasticoil spiral binding allows notebook to lie flat.
Cover contains most up-to-date Periodic Table and general lab reference information.
Table of Contents page and How to Keep a Laboratory Notebook guidelines included. View Details


Lab Notebook 100 Carbonless Pages Spiral Bound (Copy Page Perforated)
by Barbakam (Author)

No need for a carbon sheet between the pages to create a duplicate. These are carbonless self-copying pages (each page has a self duplicating page), 1/4 inch graph paper,all pages consecutively numbered, copy page is perforated for easy tear out, top page stays permanently in the notebook. Both the top page and the copy page are white for better clarity. Record of Contents page to log lab experiment information, Lab Safety Rules page, scientific reference information printed on the bi- fold back cover (ex.most up-to-date periodic table, scientific formulas, conversions, etc). Spiral Bound. View Details


Stealing Freedom
by Elisa Carbone (Author)

Inspired by a true story, the riveting novel of a young slave girl's harrowing escape to freedom on the Underground Railroad.

The moment Ann Maria Weems was born, her freedom was stolen from her. Like her family and the other slaves on the farm, Ann works from sunup to sundown and obeys the orders of her master. Then one day, Ann's family -- the only joy she knows -- is gone. Just 12 years old, Ann is overcome by grief, struggling to get through each day. And her only hope of stealing back her freedom and finding her family lies in a perilous journey: the Underground... View Details


Carbon (The Watcher Series) (Volume 2)
by AJ Eversley (Author)

Strangers become allies. Lovers become enemies. And a destiny formed before birth unfolds. Sawyer spent most of her life hunting the very thing she has now become. No longer the Watcher she once was, Sawyer struggles to make sense of her new identity. Though she now has the powers of a Carbon, she is also tied to the control Coleman has over all of his creations. Desperate for help and answers, Sawyer travels to the United Isles with Max in search of an ally. Not only must she learn to harness her new abilities, she must find a way to mend a broken heart…if her past doesn’t kill her... View Details


Carbon Fiber
by Paul Spencer (Author)

An accessible introduction to carbon fiber, its origins, science, and applications. The book contains simple explanations of complex scientific facts and beautiful images provided by the industry's best photographers. The text and photography will invite anyone to pick up a copy and enjoy the book.

View Details


Carbon Chemistry
by Ellen Johnston McHenry (Author)

Carbon Chemistry is an introduction to organic chemistry and biochemistry for ages 9-14. It is intended as a follow-up to "The Elements" by the same author, but can be used separately if the student has some basic knowledge of chemistry and the Periodic Table. The first section is a student booklet of eleven chapters, covering topics such as the carbon atom, hydrocarbons, alkanes and alkenes, functional groups, soaps, plastics, rubber, nylon, carbohydrates, fats, proteins, DNA and the carbon cycle. Despite the "heavy" nature of the topics, the text is light, easy-to-read and even humorous in... View Details


Student Lab Notebook: 100 Top Bound Carbonless Duplicate Sets
by Hayden-McNeil (Author)

100 Carbonless duplicate sets sequentially numbered.
Fully laminated front and back covers permanently bound at top of notebook.
White copy (bottom page) perforated.
Current Periodic Table on back cover folds over to prevent bleed through between sets.
3-hole punched paper.
Features tear-off ruler and general chemistry references.
Table of Contents and How to Keep a Laboratory Notebook guidelines included. View Details

Best Science Podcasts 2017

We have hand picked the best science podcasts for 2017. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Simple Solutions
Sometimes, the best solutions to complex problems are simple. But simple doesn't always mean easy. This hour, TED speakers describe the innovation and hard work that goes into achieving simplicity. Guests include designer Mileha Soneji, chef Sam Kass, sleep researcher Wendy Troxel, public health advocate Myriam Sidibe, and engineer Amos Winter.
Now Playing: Science for the People

#448 Pavlov (Rebroadcast)
This week, we're learning about the life and work of a groundbreaking physiologist whose work on learning and instinct is familiar worldwide, and almost universally misunderstood. We'll spend the hour with Daniel Todes, Ph.D, Professor of History of Medicine at The Johns Hopkins University, discussing his book "Ivan Pavlov: A Russian Life in Science."