Paper360 - May/June 2013 - (Page 30)

TECHLINK CARBON FIBERS Broadening the Availability of Carbon Fibers with Lignin The benefits carbon fibers may have in our future are limited by significant obstacles in the present TYRONE WELLS C arbon fibers are a modern biomaterial with an encouraging set of amazing mechanical properties that are set to enhance the future of civil, energy, and automotive engineering. This novel material, which is composed of highly-oriented carbon atoms, is generally several-fold stronger than steel, with only a third of the weight. Moreover, other attractive features of carbon fibers include low thermal expansion and an astonishingly high range of versatility. For example, carbon fibers can be spun into strands thinner than a human hair, or molded into rigid shapes ranging from high-end tennis rackets to next generation transportation vehicles. According to the U.S. Department of Energy, the manifold beneficial properties of this biomaterial have an immediate potential to entirely modernize the transportation industry. If implemented as a substitute for steel, carbon fibers can reduce the weight 30 Paper360º MAY/JUNE 2013 of a vehicle by nearly 60 percent without a compromise in automobile safety standards. Additionally, the reduced weight of the vehicle would directly lead to improvements in fuel economy by as much as 30 percent and a corresponding reduction in automotive emissions, based on studies performed by Oak Ridge National Laboratory. Even more compelling is that all of these advantages could be realized without any substantial changes to engine technology, and could improve the efficiency of hybrid and electric engine systems. Unfortunately, the benefits carbon fibers may have in our future are limited by significant obstacles in the present. More specifically, the widespread incorporation of carbon fibers into general consumer goods is inhibited by high production costs of the material. The high cost production of synthetic and petroleum-derived carbon fiber precursors, among other important factors, is one of the chief factors that ultimately limit the use of the biomaterial to just highperformance applications. Innovations in more cost-effective alternative carbon fiber production strategies may increase the availability of this highly useful biomaterial. ENTER LIGNIN Toward this end, scientists have examined the use of lignin, a highly abundant plantderived bioresource, as a potential carbon fiber precursor. Kraft lignin is a byproduct of the Kraft pulping process and is generally burned as fuel in pulp mill recovery boilers. Th is scenario presents an opportunity for recovery boiler-limited mills to repurpose Kraft lignin toward higher-utility applications such as high-value biomaterials. As a result, Kraft lignin has attracted significant interest as a starting material for carbon fibers. Progress to date has made it apparent that the resulting mechanical attributes of the carbon fibers rely on the quality and chemical nature of the isolated Kraft lignin. Hence, current research is now focused on discovering suitable and economic optimization processes of lignin that can benefit carbon fiber production. Professor Arthur J. Ragauskas of the Institute of Paper Science located at Georgia Institute of Technology, and Hans Thielander of Forest Products and Chemical Engineering at Chalmers Institute of Technology, are moving to the next phase of a joint research initiative towards determining novel optimizations of Kraft lignin for carbon fiber generation. Tyrone Wells, a Ph.D. candidate at the Institute of Paper Science, Georgia Institute of Technology, recently spoke on this topic at the 2013 TAPPI Student Summit. He can be contacted at Courtesy of the Gunnar Nicholson Fellowship Program, Wells will travel to Chalmers Institute of Technology, a Swedish university located in Gothenburg that focuses on research and education in technology, natural science, and architecture, to work with Professor Hans Theilander to implement upgrading strategies that will ultimately provide new insights aimed toward broadening the availability of carbon fibers derived from lignin. REFERENCES Deaton, Jamie Page, "Can carbon fiber solve the oil crisis?" 27 May 2008. HowStuff (http://auto. howstuff carbon-fiber-oil-crisis.htm). 16 January 2013. Gellerstedt, G., E. Sjoeholm, and I. Brodin, The woodbased biorefi nery: a source of carbon fiber? Open Agric. J. 4: p. 119-124. Truss, R.W., Natural fibers for biocomposites. MRS Bull. 36(9): p. 711-715. Woodyard, Chris. "Carbon fiber sparkles with diamondlike appeal," 16 July 2005. USA Today. (http://

Table of Contents for the Digital Edition of Paper360 - May/June 2013

Over the Wire . . . News Summary
The 2013 TAPPI Award Winners
Successful Asset Management in the Paper Industry from an OEM Point of View
TAPPI Journal Summaries
Managing the Risk of Fire and Explosion in the Pulp and Paper Industry
Broadening the Availability of Carbon Fibers with Lignin
TAPPISAFE Through the Eyes of a Labor Attorney
Bleached Softwood Kraft Pulp
Association News
What’s New on

Paper360 - May/June 2013