Teamwork: Great Minds Work Together

The development of Centia is the product of cross-discipline collaboration at NC State, one of the guiding principles of the university.

Dr. Bill Roberts, a professor of mechanical and aerospace engineering, and Timothy Turner, a doctoral student in mechanical engineering, began working on the problem of bio-jet fuel in response to a solicitation issued by the Defense Advanced Research Projects Agency (DARPA) in 2006. The challenge was to make jet fuel that was indistinguishable from the petroleum-based fuel that is currently in use. Although they did not receive funding from DARPA, they continued working on the project, which led to the development of Centia.

Here's how it happened:

Roberts, an expert in combustion and fuels, was able to identify the physical, chemical, and flame properties that needed to be met. Turner suggested they design a process to be able to make use of low-cost feedstocks, such as animal fats and used cooking oil. He mapped out a three-step process and did the thermodynamic analysis to determine the efficiency of energy conversion, which determines whether or not the process is economically viable.

Roberts had the idea to burn glycerol, a byproduct of step one, to provide process heat for all three reaction steps.  That reduces the amount of energy inputs needed from outside, helping to make the entire process economically viable. He designed, built and tested a swirl burner to show that the glycerol can be burned cleanly and efficiently.

Dr. Larry Stikeleather, a professor of biological and agricultural engineering who was working on biodiesel production techniques with Turner, provided expertise in the hydrolysis of fats, which is the first step of the Centia process. Stikeleather optimized the hydrolysis reaction and built a prototype 10-liter reactor. Stikeleather and Turner also began working on an alternative for the second step of the process, using gas-phase chemistry.

Dr. Henry Lamb, a professor of chemical and biomolecular engineering, developed advances in the use of catalysts for steps two and three, working with post-doctoral researcher Dr. Jason Kelly and Ph.D. student Jeremy Immer.