How to Make Hydrogen Gas From Sea Water

Oceans are enormous reservoirs of hydrogen. If properly harvested (without environmental catastrophe), it can solve many pressing energy concerns.

Oceans and seas contain vast amounts of hydrogen. Catalytic chemistry is central to efficient hydrogen production. Seawater electrolysis uses specially coated electrodes. This coating protects against unwanted side reactions. Some microorganisms give off hydrogen. They act as biological catalysts and "electrodes". To become widespread, hydrogen production from seawater must be efficient enough to compete in an open market.

Things You'll Need

• Reference and data on catalytic chemistry
• Electrodes coated with manganese dioxide (MnO2)
• Equipment to grow and manipulate hydrogen-producing microorganisms
• Data on energy production, costs, and market opportunities.

Instructions

1. Research catalytic chemistry. Catalysts affect reaction rate by lowering how much energy it takes to start a reaction. A constant amount of energy may produce hydrogen from seawater very inefficiently. Drop in a catalyst and the reaction may proceed very quickly. Seawater contains many impurities. These impurities may have a harmful effect on the intended hydrogen production. Catalysts have to withstand the chemical attack of seawater in order to be effective.

2. Use electrodes coated with manganese dioxide (MnO2). In principle, electrolysis is possible without the coating. However, uncoated electrodes quickly degrade. The UoS reference article explains why. Unwanted reactions involving sodium hypochlorite (NaClO) hinders hydrogen production. With the specially coated electrodes, seawater electrolysis gives hydrogen molecules with far less corrosive effects on the metal electrodes.

3. Utilize bacteria and/or plankton to expel hydrogen. Certain aquatic microorganisms expel hydrogen as a waste product. Growing and "harvesting" these organisms can aid attempts to extract hydrogen from seawater. If a friendly growth environment is present, the hydrogen-expelling bacteria can increase hydrogen supply over time. This trend is in contrast to "artificial" means such as electrolysis and catalyzed reactions. Fabricated chemicals and parts eventually wear out and degrade.

4. Calculate which production method (if any) may be commercially viable. New energy production has to compete with established names and brands, as with any industry or sector. Forbes Magazine has a flowery perspective on hydrogen in "Energy Revolution is Just Beginning". Nevertheless, the article makes a salient point: the hydrogen energy equivalent of a gallon of gasoline costs less than 50 cents as of July 2010. That is progress over previous research, especially on larger production size scales.

Tips & Warnings

• "Energy equivalency" refers to how much usable energy a fuel type can provide with current technology. The Forbes Magazine quotation does not mean that it takes less than 50 cents to make a gallon of hydrogen. Rather, it takes a bit less than 50 cents to make the amount of hydrogen---what the amount is, in terms of mass or volume, remains unspecified--that would generate as much energy as would a gallon of gasoline.

References

• Department of Chemistry, Texas A&M University: Catalytic Kinetics
• Food and Agriculture Organization of the United Nations (FAO): Hydrogen Production
• Royal Society of Chemistry: Producing Hydrogen From Seawater
• Energy Systems Research Unit, University of Strathclyde (UoS): Hydrogen--Production
• Forbes Magazine: Hydrogen Fuel---Energy Revolution is Just Beginning