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By Shane Lasley
Mining News 

Graphite makes its mark on 21st Century

From mundane to miraculous, traditional and emerging uses drive demand for new supplies of the versatile carbon polymer

 

Last updated 3/25/2012 at Noon



Possessing neither the brilliance of diamonds nor the thermal-producing capabilities of coal, graphite is the middle sibling of the carbon family. Until recently, it has largely gotten by on its heat-resistant attributes. Some 70 percent of the 1.1 million metric tons of natural graphite consumed in 2011 was used in making steel and in automotive and lubrication applications.

But scientists today are finding new uses for the two-dimensional carbon polymer.

During a February interview with The Critical Metals Report, Technology Metals Research co-founder Jack Lifton spoke about the traits that are making graphite an important ingredient in advanced technology manufacturing.

"Graphite and diamonds are the only two natural polymers of carbon. Both are very strong, can withstand extreme heat, and resist attack from chemicals and corrosion. While a diamond is a three-dimensional crystal structure of carbon, graphite possesses a two-dimensional flake crystal structure," he explained. "Graphite is also a very good conductor of heat and electricity. Due to its amazing chemical and physical properties, new industrial, commercial and high-technology uses for graphite are constantly being discovered."

Graphite is a key ingredient in the manufacture of lithium-ion batteries, an important demand-driver of the mineral in the near-term.

"Graphite serves as the anode in lithium-ion batteries, and there is no substitute for it in this application. Due to their advantages relative to other battery types-including their comparatively light weight, lack of memory effect, slow self-discharge rate and environmental safety -the lithium-ion battery industry is growing 30-40 percent annually as products such as power tools, consumer electronics, and hybrid and all-electric vehicles switch from other, inferior battery technologies," Lifton said.

Scientists also recently discovered a way to slice graphite into one-atom-thick sheets of carbon known as graphene, the strongest and most conductive material known to man.

The new applications are expected to more than double the demand for graphite in the next few years.

This trend has sparked interest in exploration for new sources of graphite, including a project recently undertaken by Graphite One Resources Inc., formerly Cedar Mountain Exploration Inc., to explore the Graphite Creek property located about 65 kilometers (40 miles) north of Nome, Alaska.

Pencils and cannonballs

The use of graphite can be traced to around the 4th millennium B.C., where it was used as an ingredient of pottery paint by some southern Europeans. The mineral, though, made its first real mark on the human economy sometime during the first half of the 16th Century.

The turning point for graphite came when the locals of the Borrowdale parish of northern England discovered a plentiful supply of soft black rocks that could be easily carved into sticks and used as marking implements. Graphite, which was later named after the Greek word to write or draw, replaced harder and toxic lead as the inscription mineral of choice and led to the advent of the pencil.

Around 1565 the government of England discovered that moulds carved from the graphite at Borrowdale produced cannonballs that were rounder and smoother than those cast with traditional materials of the day. The longer range and truer trajectory of these 16th Century missiles is said to have contributed to the growing superiority of the English navy. The militaristic importance of graphite prompted the Crown to exert exclusive control over the Borrowdale deposit.

Due to its high melting point - around 3,650 degrees Celsius (6,600 degrees Fahrenheit) - graphite continues to be an important refractory material. In addition to its continued use in moulds, the carbon polymer is utilized in the production of fire bricks, crucibles and ladles for containing molten metals.

According to the U.S. Geological Survey, about 63 percent of the some 56,000 metric tons of graphite consumed in the United States in 2010 was used for refractory, foundry and steelmaking purposes. Brake and clutch linings made up 8 percent of domestic consumption and lubrication accounted for 3 percent. The USGS lumped the remaining 26 percent into other applications.

Global graphite production is estimated to be around 1.2 million metric tons in 2011, with some 65 percent being supplied by China.

The largest portion of the graphite produced in China is classified as amorphous or small flake. While a satisfactory ingredient for many industrial applications, this lowest form of graphite is not desirable for higher end purposes.

"China's production is suitable only for industrial applications such as steelmaking and lubrication rather than high-tech uses like batteries and graphene," Lifton said.

Large flake graphite containing more than 94 percent carbon is the variety being sought after for high-technology applications.

Powerful ingredient

While traditional uses continue to dominate the graphite market, the rechargeable lithium-ion battery is an increasingly important application and is expected to overtake industrial applications in the next five to 10 years.

"The lithium-ion battery is one of the fastest-growing uses of graphite. Each one actually contains greater than 10 times more graphite than lithium. These batteries are already widely utilized in the consumer electronics industry in devices like mobile telephones, laptop and tablet computers, and media players," explains Lifton.

Like the pencil in the 16th Century, graphite is in a position to become the lead of the 21st Century car battery.

"Both U.S. President Barack Obama and Chinese leaders have stated that they want to see 1 million electric vehicles on the roads by 2015," Lifton said.

Lithium-ion batteries are currently the power source of choice in the electric vehicle market.

Canaccord Research estimates that if electric and hybrid electric vehicles each gained a 10 percent foothold in the automotive market by 2020, the amount of flake graphite needed for this sector alone would be around 1.27 million metric tons per year, or more than triple the 2011 production of this variety of the carboniferous mineral.

"Annual flake graphite production will have to increase by a factor of six by 2020 to meet incremental lithium carbonate requirements for batteries," according to a Canaccord research report.

Fuel cells - which not only store energy but generate electricity through a chemical process - are another emerging use for graphite. Currently being used in vehicles ranging from bicycles to submarines - fuel cells show promise as a quiet, zero-emissions alternative power source.

Forklifts are currently the most common users of fuel cells, where they have been found to outperform both petroleum and battery powered forklifts on several fronts.

"Other new technologies like fuel cells also will drive demand. Fuel-cell-powered forklifts are in use in American warehouses. Some fuel-cell-powered taxis and buses are already found on city streets, and most major car companies will join Hyundai in producing fuel cell vehicles by 2015," explained Lifton.

"The proton exchange membrane fuel cells being developed for use in cars would require 100 pounds of graphite per vehicle," he added.

In its 2012 Mineral Commodity Summaries, the USGS notes that large-scale fuel-cell applications currently under development could consume as much graphite as other uses of the carbon polymer combined.

Researchers envision fuel cells small enough to power a cell phone and large enough to incorporate into the power-grid.

Miraculous graphene

Said to be the strongest and most conductive material ever measured, graphene has been dubbed a miracle material of the 21st Century.

A layer of graphene consists of a single layer of carbon atoms arranged in a hexagonal lattice that is most easily visualized as an atomic-scale version of chicken wire. It would take a stack of 3 million sheets of this truly two-dimensional material to measure 1-millimeter thick.

Professors Kostya Novoselov and Andre Geim of the University of Manchester, who first isolated a single layer of graphene in 2004, were awarded the 2010 Nobel Prize in Physics for their work with this "miracle material."

Though graphene technology is in its infancy, applications of this carbon material are seemingly endless.

"Our research establishes graphene as the strongest material ever measured, some 200 times stronger than structural steel," Columbia University Professor James Hone said. "It would take an elephant, balanced on a pencil, to break through a sheet of graphene the thickness of Saran Wrap."

Despite its strength, graphene is both elastic and flexible. These traits coupled with the materials conductivity is driving the first generation of graphene products toward commercial production.

"In collaboration with South Korea's Sungkyunkwan University, Samsung researchers have created a flexible touchscreen several feet wide from 'printed' graphene that could eventually be commercialized in strong, lightweight, flexible solar cells, touch sensors and flat-panel screens, perhaps maybe even directly integrated into clothing," according to Lifton.

Mobile phone-giant Nokia is studying the use of graphene as an inexpensive replacement material for touch screens. Using graphene technology, the Nokia Morph could become the world's first foldable phone. While still a concept, it has been hinted that the device could be ready for production within a year.

From mundane to miraculous, the traditional and emerging uses of graphite are driving demand for new supplies of the versatile carbon polymer.

"This booming demand will require more than a doubling of current global graphite production to meet the needs of traditional markets like North America and Europe, as well as such emerging markets as China, India, Russia and Brazil, Lifton said. "Fortunately, graphite reserves are present around the world, though many sites would require several years of development and significant investment to begin production."

Author Bio

Shane Lasley, Publisher

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Over his more than 16 years of covering mining and mineral exploration, Shane has become renowned for his ability to report on the sector in a way that is technically sound enough to inform industry insiders while being easy to understand by a wider audience.

 

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