|C. perfringens, H2 Producer|
Dennis Kunkel Microscopy, Inc.
NanoLogix, formerly InfecTech (earlier post), has signed an agreement to generate hydrogen from a scaled-up bio-reactor system using waste organic matter from a winery as feedstock for hydrogen-producing bacteria.
There are two basic approaches to the microbial production of hydrogen: fermentative and photosynthetic. Clostridia species, methanogens and archeabacteria are known fermentative producers of hydrogen, while purple sulfur bacteria and green algae are examples of photosynthetic producers.
There are a number of requirements to be met for such a bioconversion process to be commercially viable. One is to keep the bacterial culture healthy and thriving. Another is to increase the stability of the process and the conversion yield to the point of commercial utility.
NanoLogix, originally founded in 1989 for the development of diagnostic kits for infectious diseases, is diversifying into technologies for the biological production of alternative sources of fuel and the remediation of toxic materials. It uses its patented bacterial culturing methods with Clostridia for the hydrogen production.
In a natural fermentative process, some of the hydrogen produced by Clostridia would be used (inter-species transfer) by methane-producing bacteria (methanogens) in the inoculum. Reducing or eliminating the methanogens is one approach to increasing the ultimate yield of hydrogen.
Researchers have found that heat treatment is one of the effective techniques for accomplishing that.
A Clostridium bacterium will form a bacterial spore in the presence of heat, and survive. The methanogens are non-spore-forming; the heat kills them. The application of the heat process thus effectively selects for the Clostridia population and so for production of hydrogen while eliminating the competing process of methanogenesis.
NanoLogix’ process is based on combining the bacterial production of hydrogen with excess industrial heat.
NanoLogix recently announced that preliminary data and results of a study which confirms laboratory proof-of-concept measurements have shown it possible to generate hydrogen in high yields via the use and adaptation of its intellectual property. In this study, the bioreactor produced biogas consisting of 50% hydrogen by volume, without any trace of methane.
Hydrogen Production by Anaerobic Microbial Communities Exposed to Repeated Heat Treatments, Proceedings of the 2002 US DOE Hydrogen Program Review, NREL/CP-610-32405
The Relative Effectiveness of pH Control and Heat Treatment for Enhancing Biohydrogen Gas Production, Environ. Sci. Technol., 37 (22), 5186-5190, 2003
Removal of Headspace CO2 Increases Biological Hydrogen Production, Environ. Sci. Technol., 39 (12), 4416-4420, 2005.