derailment leads to ethanol fire

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NEWS OF THE WEEK SPLITTING WATER CREATES ALLOY RADIATION CHEMISTRY: X-rays cause ice under pressure to form H 2 -0 2 solid Z APPING ICE VII—a crystalline form of water that occurs at high pressure and ambient tem- perature—with X-rays cleaves the O-H bonds and creates a novel crystalline solid composed of molecular hydrogen and oxygen (Science 2006,314, 636). The finding, reported by a multi- institutional team, opens up new avenues for high-pressure ra- diation chemistry. "There are so many studies on water, you wonder, how can there be anything more to find?" says Wendy L. Mao, a postdoc- toral fellow at New Mexico's Los Alamos National Laboratory who spearheaded the research. But the new UNDER PRESSURE The brown smear in the left image indicates where X-rays struck ice VII under high pressure, forming a crystalline com- pound of 0 2 and H 2 . Gas bubbles out of this ma- terial when the pressure is released (right). material looks different from what has been seen be- fore, she adds. Mao's team—including her father, Ho-kwang Mao, and Russell J. Hemley of the Carnegie Institution of Washington, as well as Peter J. Eng of the University of Chicago—made the unexpected discovery while trying out a new high-pressure synchrotron X-ray technique that irradiates substances with moderately high-energy X-rays for long periods of time. "At first, we saw these unexpected H 2 and 0 2 peaks in our X-ray Raman spectra," Wendy Mao tells C&EN. "Then we released pressure from the diamond anvil cell, and we actually saw gas bubbling out." Upon further investigation, they determined that at high pressure the X-rays dissociate H 2 0 and the result- ing atoms recombine into a previously unknown solid of H 2 and 0 2 . This new "alloy" is spectroscopically dis- tinct from a simple H 2 -0 2 mix. X-rays are known to create free radicals and instigate reactions at ambient pressure, but examples of similar transformations at high pressure are rare. "We man- aged to hit on just the right level of X-ray energy input," Hemley explains. "Any higher, and the radiation tends to pass right through the sample. Any lower, and the radiation is largely absorbed by the diamonds in our pressure apparatus." The new alloy exhibits surprising stability, so long as it's kept at high pressure. Six months after the original experiments, the material hasn't reverted to ice VII, Mao says, even after heating it to 700 Κ and blitzing it with lasers and X-rays.—BETHANY HALFORD Norfolk Southern train carrying ethanol derailed in New Brighton, Pa., over the Beaver River. DERAILMENT LEADS TO ETHANOL FIRE EXPLOSION: Growing market for ethanol puts more pressure on rails T WENTY-THREE RAILCARS in an 86 tanker long train carrying ethanol derailed on Oct. 20, leading to an explosion and fire near New Brighton in ru- ral Pennsylvania, 25 miles north of Pittsburgh. The Nor- folk Southern cars derailed near a bridge over Beaver River, and many wound up in the river. No one was hurt in the accident, but some 100 people were evacuated. The company would not release figures on the amount of ethanol spilled or the total amount the train carried, Rudy Husband, a company spokesman, tells C&EN. But he says each tanker has a capacity of 30,000 gal. More than 80% of the nearly 5 billion gal of ethanol made in the U.S. this year is shipped by rail, says Ron Lamberty, vice president for market development with the American Coalition for Ethanol, an association of ethanol-related businesses and ethanol supporters. The rest goes by barge or truck. Unlike for gasoline, there are no pipelines for ethanol. Because ethanol is water soluble, it must be isolated from water, a fact that makes its handling difficult. And there are other problems with pipeline transportation for this fuel. For gasoline, Lamberty notes, a system of pipelines takes refined gas from the coasts, mostly Texas and Louisiana, to the rest of the country. "There are about 250 billion gal of fuels moving around the country," Lamberty says, "but ethanol is only about 5 billion gal. It is an insignificant amount." And for ethanol the flow must go the other way. "We've talked about a pipeline running from the Mid- west to the East or West Coast, but the question is whether it would be economical," Lamberty adds. Meanwhile, ethanol production and use is encour- aged by the government, and the amount produced by U.S. companies continues to increase. "This is a growing business for us," Husband says. He refuses to give shipment numbers, however, saying this would aid Norfolk Southern's competitors. Railroads maintain that they have the capacity to handle the added cargoes, a fact underscored by Hus- band, who adds that the Oct. 20 accident was the only ethanol accident he could remember—JEFF JOHNSON WWW.CEN-0NLINE.ORG \Q OCTOBER 30, 2006

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NEWS OF THE WEEK

SPLITTING WATER CREATES ALLOY

RADIATION CHEMISTRY: X-rays cause ice under pressure to form H2-02 solid

ZAPPING ICE VII—a crystalline form of water that occurs at high pressure and ambient tem­perature—with X-rays cleaves the O-H bonds

and creates a novel crystalline solid composed of molecular hydrogen and oxygen (Science 2006,314,

636). The finding, reported by a multi-institutional team, opens up new avenues for high-pressure ra­diation chemistry.

"There are so many studies on water, you wonder, how can there be anything more to find?" says Wendy L. Mao, a postdoc­toral fellow at New Mexico's Los Alamos National Laboratory who spearheaded the research. But the new

UNDER PRESSURE The brown smear in the left image indicates where X-rays struck ice VII under high pressure, forming a crystalline com­pound of 0 2 and H2. Gas bubbles out of this ma­terial when the pressure is released (right).

material looks different from what has been seen be­fore, she adds.

Mao's team—including her father, Ho-kwang Mao, and Russell J. Hemley of the Carnegie Institution of Washington, as well as Peter J. Eng of the University of Chicago—made the unexpected discovery while trying out a new high-pressure synchrotron X-ray technique that irradiates substances with moderately high-energy X-rays for long periods of time.

"At first, we saw these unexpected H2 and 0 2 peaks in our X-ray Raman spectra," Wendy Mao tells C&EN. "Then we released pressure from the diamond anvil cell, and we actually saw gas bubbling out."

Upon further investigation, they determined that at high pressure the X-rays dissociate H20 and the result­ing atoms recombine into a previously unknown solid of H2 and 02 . This new "alloy" is spectroscopically dis­tinct from a simple H2-02 mix.

X-rays are known to create free radicals and instigate reactions at ambient pressure, but examples of similar transformations at high pressure are rare. "We man­aged to hit on just the right level of X-ray energy input," Hemley explains. "Any higher, and the radiation tends to pass right through the sample. Any lower, and the radiation is largely absorbed by the diamonds in our pressure apparatus."

The new alloy exhibits surprising stability, so long as it's kept at high pressure. Six months after the original experiments, the material hasn't reverted to ice VII, Mao says, even after heating it to 700 Κ and blitzing it with lasers and X-rays.—BETHANY HALFORD

Norfolk Southern train carrying ethanol derailed in New Brighton, Pa., over the Beaver River.

DERAILMENT LEADS TO ETHANOL FIRE EXPLOSION: Growing market for

ethanol puts more pressure on rails

TWENTY-THREE RAILCARS in an 86 tanker long train carrying ethanol derailed on Oct. 20, leading to an explosion and fire near New Brighton in ru­

ral Pennsylvania, 25 miles north of Pittsburgh. The Nor­folk Southern cars derailed near a bridge over Beaver River, and many wound up in the river. No one was hurt in the accident, but some 100 people were evacuated.

The company would not release figures on the amount of ethanol spilled or the total amount the train carried, Rudy Husband, a company spokesman, tells C&EN. But he says each tanker has a capacity of 30,000 gal.

More than 80% of the nearly 5 billion gal of ethanol made in the U.S. this year is shipped by rail, says Ron Lamberty, vice president for market development with the American Coalition for Ethanol, an association of ethanol-related businesses and ethanol supporters.

The rest goes by barge or truck. Unlike for gasoline, there are no pipelines for ethanol.

Because ethanol is water soluble, it must be isolated from water, a fact that makes its handling difficult. And there are other problems with pipeline transportation for this fuel.

For gasoline, Lamberty notes, a system of pipelines takes refined gas from the coasts, mostly Texas and Louisiana, to the rest of the country.

"There are about 250 billion gal of fuels moving around the country," Lamberty says, "but ethanol is only about 5 billion gal. It is an insignificant amount."

And for ethanol the flow must go the other way. "We've talked about a pipeline running from the Mid­west to the East or West Coast, but the question is whether it would be economical," Lamberty adds.

Meanwhile, ethanol production and use is encour­aged by the government, and the amount produced by U.S. companies continues to increase.

"This is a growing business for us," Husband says. He refuses to give shipment numbers, however, saying this would aid Norfolk Southern's competitors.

Railroads maintain that they have the capacity to handle the added cargoes, a fact underscored by Hus­band, who adds that the Oct. 20 accident was the only ethanol accident he could remember—JEFF JOHNSON

WWW.CEN-0NLINE.ORG \Q OCTOBER 30, 2006