Emitted by manure and sewer pipes, Hydrogen sulphide – also known as sewer gas – is not only unpleasant to smell but also poisonous and corrosive. However, scientists have discovered a process to convert this foul-smelling gas into clean energy.
The researchers said that transforming this gas to hydrogen fuel creates an alternative energy source to oil and gas, which are significant contributors to climate change.
“Hydrogen sulphide is one of the most harmful gases in industry and to the environment,” said Lang Quin, a co-author on the study and research associate in chemical and biomolecular engineering, Ohio State University “..and because the gas is so harmful, we want to turn hydrogen sulphide into something that is preferably valuable.
”According to the study, the process uses little energy and cheap material, with only the chemical iron sulphide with a trace amount of molybdenum as an additive.
To convert the sewer gas into clean energy, the researchers use a process called chemical looping, which uses a solid material to break down a chemical reaction into many smaller sub-reactions – in this case, using metal oxide particles to circulate oxygen and burn fuel. This process has been used previously to burn fossil fuels like coal without emitting carbon dioxide, and now the team has found a way to apply the same principle to transform hydrogen sulphide into just hydrogen, which can be used as fuel.
According to Kalyani Jangam, lead author of the study and a graduate student in Ohio State’s Clean Energy Research Laboratory, it is too soon to tell if this research can replace any other hydrogen fuel production technologies available in their work is a viable alternative. However, they hope to perform tests at a larger scale in the near future.
“The big picture is we want to solve the harmful gas issue, and we thought that our chemical looping process would allow that,” Qin added.
The research is published in the journal ACS Sustainable Chemistry & Engineering.