Cullinan, Krishnagopalan develop pulping process for high-yield biofuels

Published: Dec 4, 2009 4:26:00 PM
Media Contact: Sally Credille,, 334.844.3447

As part of a joint venture agreement between Auburn University and the U.S. Department of Agriculture's Forest Service Forest Products Laboratory, chemical engineering faculty members Harry Cullinan and Gopal Krishnagopalan have developed a selective and efficient pre-extraction and modified pulping process for softwood that maintains yield and pulp quality.

A large fraction of hemicelluloses in wood chips is dissolved into black liquor during the pulping process. This portion is essentially wasted, as only its fuel value is recovered. Integrating biorefineries with existing forest based industries would allow for significant economic growth through new value-added products and higher resource utilization. Recovery of the hemicelluloses was achieved by prehydrolyzing the wood chips using hot water, steam or acid to remove the hemicelluloses before the pulping process. The major effect that needed to be researched was the quality of the pulp and paper products produced from prehydrolyzed wood chips. The process will now be scaled up for testing in a lab digester, which will involve additional work to screen less expensive additives for pretreatment and optimize pretreatment and cooking conditions.