New biobattery for hydrogen storage
Microbiologists has succeeded in using bacteria for the controlled storage and release of hydrogen
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Goethe-Universität Frankfurt am Main
“The measured rates of CO2 reduction to formic acid and back are the highest ever measured and many times greater than with other biological or chemical catalysts; in addition, and unlike chemical catalysts, the bacteria do not require rare metals or extreme conditions for the reaction, such as high temperatures and high pressures, but instead do the job at 30°C and normal pressure,” reports Müller. The group now has a new success to report: the development of a biobattery for hydrogen storage with the help of the same bacteria.
For municipal or domestic hydrogen storage, a system is desirable where the bacteria first store hydrogen and then release it again in one and the same bioreactor and as stably as possible over a long period of time. Fabian Schwarz, who wrote his doctoral thesis on this topic at Professor Müller’s laboratory, has succeeded in developing such a bioreactor. He fed the bacteria hydrogen for eight hours and then put them on a hydrogen diet during a 16-hour phase overnight. The bacteria then released all the hydrogen again. It was possible to eliminate the unwanted formation of acetic acid with the help of genetic engineering processes. “The system ran extremely stably for at least two weeks,” explains Fabian Schwarz, who is pleased that this work has been accepted for publication in “Joule”, a prestigious journal for chemical and physical process engineering. “That biologists publish in this important journal is somewhat unusual,” says Schwarz.
Volker Müller had already studied the properties of these special bacteria in his doctoral thesis – and spent many years conducting fundamental research on them. “I was interested in how these first organisms organised their life processes and how they managed to grow in the absence of air with simple gases such as hydrogen and carbon dioxide,” he explains. As a result of climate change, his research has acquired a new, application-oriented dimension. Surprisingly for many engineers, biology can produce by all means practicable solutions, he says.