America's Center in downtown St. Louis, Mo., hosted the American Oil Chemists Society's (AOCS) 97th Annual Meeting & Expo on April 29-May 3. Conferees came to the meeting to learn about and discuss various oleochemical topics, but interest in biodiesel was distinctly high this year. A two-day pre-conference short course on biodiesel kicked off the event, with the exposition and technical sessions following.

The Short Course on Biodiesel: Market Trends, Chemistry and Production hosted a number of representatives from a diverse group of companies simply looking to learn more about biodiesel. "There was a time when I would know almost everyone in the room at this type of course," said National Biodiesel Board Technical Director Steve Howell, elucidating the shift in interest from the once-niche gathering of research and industry insiders to an attendance from a wide spectrum of fields.

Two technical sessions, called Alternative Fuels I & II, addressed issues relating to the biodiesel industry. John Massingill of Texas State University presented an advanced fiber-based neutralization process that would eliminate centrifuging. According to Massingill, advantages of using this trademarked Fiber-Film technology seen in lab-scale trials include short contact time on the high surface area of the trademarked Fiber-Film in a fast, clean reaction. Results showed a 90 percent removal of free fatty acids in neat oils (up to 1 percent by volume). Other benefits incorporate reduced energy consumption with the elimination of capital and maintenance costs associated with centrifuges.

Novel feedstock discussions also took place. Karryanne Leroux from the Energy and Environmental Research Center (EERC) in Grand Forks, N.D., introduced an ongoing project to determine the feasibility of Cuphea oils as potential feedstocks for biodiesel. The seeded species of flowers in the Cuphea genus are native to North America and contain double the amount of oil per acre compared to soybeans. Leroux said its chemical properties also give way to better cold flow characteristics. USDA agricultural researcher Ronald Holser presented findings from the evaluation of milkweed seed oil as another outside-the-box feedstock. Holser said biodiesel from this oil, although lower in oxidative stability compared to soy biodiesel, has several other beneficial properties.

AOCS chair and USDA researcher Michael Haas presented results from his team's economic process model that compared costs from conventional means of biodiesel production versus those associated with in situ transesterification. With many assumptions plugged into the model, Haas' team found substantially higher utilities costs from in situ production because of the elevated energy levels required to recoup the high volume of excess methanol used to complete its reactions. Alcohol reduction is critical to making in situ transesterification economically competitive, Haas said.

Rose Patzer from the Agricultural Utilization Research Institute presented analyses of differing material deposits from four plugged fuel filters in Minnesota. Minnesota's B2 mandate, implemented in October, was suspended a second time when filters began plugging throughout the state last winter. A few samples showed evidence of microbiological degradation. One of Patzer's conclusions stated that the upset in Minnesota's B2 mandate was caused in part by lax storage tank maintenance and off-spec biodiesel. Many variables not yet isolated could have also contributed to the widespread filter plugging. Among many other ideas, the oxygen that alkyl esters bring to a biodiesel blend was said to possibly facilitate microbial growth at the water-fuel interface.