Researchers discover way to generate hydrogen fuel from sea water
October 2, 2020The Penn State team use membranes to extract the salt from the water to help split the molecule.
A team of Penn State researchers have found a way to produce hydrogen fuel from sea water using purification technology integrated into a new proof-of-concept electrolyzer design.
This method uses electric current to split the water molecules into the fuel and oxygen.
The idea behind being able to make hydrogen fuel from sea water is to make it easier to power green fuel generation through wind and solar energy. In this way, these renewable sources of electricity can be converted into fuel that can be stored and transported, said Bruce Logan, professor of environmental engineering and Evan Pugh University professor.
“Hydrogen is a great fuel, but you have to make it,” said Logan. “The only sustainable way to do that is to use renewable energy and produce it from water. You also need to use water that people do not want to use for other things, and that would be sea water. So, the holy grail of producing hydrogen would be to combine the sea water and the wind and solar energy found in coastal and offshore environments.”
Hydrogen fuel from sea water is not a common process, despite the abundance of the source.
The issue is that the salt in ocean water must be removed before it can enter the electrolyzer. Desalinating is an expensive process, which has meant that this source of water has not had much appeal for traditional H2 production. If the salt were to be left in place during electrolysis, the chloride ions convert into toxic chlorine gas, which damages both the equipment and the environment.
In order to prevent such damage, the research team used a thin, semipermeable membrane. The membrane was originally developed for reverse osmosis (RO) water purification treatment. That membrane replaced the ion-exchange membrane that is a typical component in electrolyzers.
“The idea behind RO is that you put a really high pressure on the water and push it through the membrane and keep the chloride ions behind,” explained Logan.
During this process of producing hydrogen fuel from sea water, the water would not be forced through the RO membrane. Instead, the membrane would contain it. The membrane is employed for separating reactions taking place near two submerged electrodes – a negatively charged cathode and a positively charged anode – which are connected by way of an external source of electricity. Once the electricity is turned on, the water splits near the anode, releasing protons (hydrogen ions) and producing oxygen gas. From there, the protons pass through the membrane to the cathode where they combine with electrons and form H2.
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solution to non-existant problem, use large global condensation system called rain
Off peak hydro and atomic generation power plant generation and usage should be the time that hydrogen is produced for storage and transmission or to be fed back into the grid during periods of high demand.
Existing rights of way could facilitate pipe lines for shipment of this clean source of hydrogen for use as a fuel or use in fuel cell applications
I have difficulty determining the “discovery”expressed in the article title. Desalination is usually requisite before electrolysis of seawater. RO membranes are often used.
Wasn’t H Power was doing this for the US Navy more than 30 years ago?
Few people realize that ocean water must be used to produce hydrogen and oxygen in the future. There is not enough fresh water to allow using hydrogen as a replacement for gasoline over an extended period of time. Hydrogen is the most likely energy source to replace fossil fuels and must come from using sunlight and ocean water. Oxygen will be released into the atmosphere and ocean water minerals captured. Best not to deplete fossil fuel reserves with no viable replacement and rely on fusion energy.
Energy for the world, endless energy, and a solution for climate change.
If an electrolyzer is used in conjunction with a bank of fuel cells to generate electricity back, a good fraction of the water consumed in the electrolyzer could be recovered in the fuel cells and recycled into the electrolyzer after purification. Such combination of an electrolyzer with fuel cells are essential to make solar and wind systems dispatchable.
Need to explore and develop in malaysia
Submerging both the electrolysis electrodes and membranes to appropriate depth in the sea within appropriate piping allows the process to generate pressurized gas in the connecting piping with no additional hardware. Installing a small submersible pump in the connecting piping would allow for fresh water recovery. A check valve at the bottom would allow initial filling with fresh water, displacing any saline. Electrolysis lowers this water level, and at a calculated point the DP across the membrane at the bottom would force the fresh water through, maintaining proper level. An deep sea submergence installation could supply fresh water, pressurized O2 & H2.
Good Idea, water depth vs salinity of water in sea seems viability of the project, provided electrolysis process is independent of pressure inside the container, which I believe so. Any proof of concept?
Does the membrane clog up similar to the ones in the RO process?