Hydrogen from Dirty and Clean Sources

Dean Sigler Fuel Cells, Hydrogen Fuel, Sustainable Aviation Leave a Comment

Hydrogen, the first element created from the Big Bang, is the lightest in the periodic table, has the atomic number 1, and is “the most abundant chemical substance in the universe.” (Wikipedia).  Until starting this blog entry, though, your editor was unaware that this colorless gas came in brown, blue, and green variants – referring to the methods used to extract h2.  Hydrogen can be extracted from some fairly dirty sources, but the dirtiest may lead to an amazingly clean outcome, if we’re to believe what’s happening in Lancaster, California. The Guardian reports, “Broadly, there are currently three ways to make hydrogen. Brown hydrogen is produced when the element is stripped out of fossil fuels such as coal, while blue hydrogen is produced from gas. Green hydrogen is produced from running an electric current through water using an electrolyser powered by renewable energy such as solar.”  (A simplified list) Brown H2 from Brown and Black Coal Brown coal has more …

As Common As It Gets – But Hard to Get

Dean Sigler Electric Powerplants, Sustainable Aviation Leave a Comment

Since Michael Faraday first split water into hydrogen and oxygen in 1820, scientists have puzzled over how to do this economically in large quantities.   The Blog continues to run stories about “artificial leaves,” low-energy approaches to dividing the hydrogen in water from the oxygen, and doing so economically.  The current most widely-used approach to capturing hydrogen is pulling it from natural gas via several processes.  The Office of Energy Efficiency and Renewable Energy explains the process on its web site. Steam-methane Reforming In steam-methane reforming, “high-temperature steam (700°C–1,000°C) is used to produce hydrogen from a methane source, such as natural gas. In steam-methane reforming, methane reacts with steam under 3–25 bar pressure (1 bar = 14.5 psi) in the presence of a catalyst to produce hydrogen, carbon monoxide, and a relatively small amount of carbon dioxide. Steam reforming is endothermic—that is, heat must be supplied to the process for the reaction to proceed.” In a “’water-gas shift reaction,’ the carbon …