December 23, 2013
Creating sustainably produced biofuels from waste may eventually become a greener, less energy-intensive process thanks to work by a group of West Chester University biology students.
Undergraduates Joseph R. Mossman and William Schultz and graduate-level student Zehra Zaybak were honored with an international award for their project “Enhanced waste-to-fuel conversion with a bioelectrochemically controlled autotrophic bioreactor.” In layman's terms, the students used a minute electrical stimulus to promote the formation of biogas – combustible methane and non-combustible carbon dioxide (CO₂) – from wastewater while actively growing algae efficiently removed the CO₂. The algae used in the process is autotrophic: It can synthesize its own food from inorganic substances using light or chemical energy. WCU microbiologist John M. Pisciotta says his students' experiment is the first he knows of "that couples autotrophic biogas processing with electrically enhanced biogas production."
Guided by Pisciotta, the students measured real-time rates of CO₂and methane production and removal using sensors and other gas analysis technology from BlueSens, a German manufacturer. The company offers an educational loan of equipment and sponsors an international competition for universities that use its products. The West Chester students placed second behind a team of graduate students from Clemson University's departments of Electrical & Computer Engineering and Bioengineering. The breakdown of organic waste matter – from food scraps to sewage – is a long process. Pisciotta explains that the use of anaerobic digestion is just starting to take off in North America but it is already popular in Europe for production of renewable bio-methane for fuel. Unfortunately, separation of the CO₂portion from the combustible bio-methane usually requires energy-intensive mechanical processing.
"We applied voltage to environmental bacteria to promote breakdown of the waste into biogas. In a second stage, algae biologically scrubbed out CO₂by converting it to living cellular material. The liquid nutrients that are left behind by this process can be used as a low-cost fertilizer. The matured algae can in turn be used as a protein-rich animal feed or can be converted into other products, like biodiesel."
With their prize money, the team plans to further develop this promising technology at West Chester.
Pisciotta is an assistant professor of biology who teaches industrial microbiology and microbial physiology. Mossman of Springfield, Pa., is a senior majoring in microbiology; Schultz of Scranton, Pa., is a senior majoring in general biology with a chemistry minor; and Zaybak from Berlin, Germany, is a professional-growth graduate student in physics.