For those of you who are still rooting for hydrogen fuel cells to lead the world into an emissions free future, there’s good news. Professor Richard O’Hair and a team of scientist as the University of Melbourne have devised a new chemical process they say unlocks hydrogen from formic acid in a way that is much less expensive than traditional methods.
But first, what is formic acid? According to Wikipedia, “Formic acid is the simplest carboxylic acid. The chemical formula is HCOOH or HCO2H. It is an important intermediate in chemical synthesis and occurs naturally, most notably in some ants. The word ‘formic’ comes from the Latin word for ant, formica, referring to its early isolation by the distillation of ant bodies.”
You don’t need an advanced degree in chemistry to realize there are two hydrogen atoms in each molecule of formic acid. Break the chemical bonds between them and the other atoms and you get lots of free hydrogen. Just the thing for powering the fuel cells in automobiles.
Previously, it took very high temperatures and lots of energy to break those bonds and set the hydrogen free. But O’Hair and his colleagues say their process works at temperatures as low as 70º Celsius.
“One of the grand challenges for chemists today is to develop perfect chemical reactions that proceed with 100 per cent yield and 100 per cent selectivity without forming any waste products,” Professor O’Hair says. “With formic acid, the aim was to transform it into hydrogen and carbon dioxide, which could really lend itself to the important practical applications of hydrogen energy in the transport sector.”
Using a suite of powerful gas-phase techniques, the research team designed a series of silver complexes and examined their reactions with formic acid. The team was able to identify and orchestrate the exact catalyst that would effectively manipulate a strict hydrogen/carbon dioxide-only production.
Athanasios Zavras, the study’s lead author and a PhD student at the University of Melbourne, says having the initial gas-phase results validated using a nuclear magnetic resonance (NMR) instrument was an exciting moment. “It was an extremely exciting moment. We were glued to our seats that day,” he says.
“I prepared solutions containing well-defined amounts of the same silver, salt and ligand combination and these were studied with a NMR that allowed us to incrementally increase the temperature from 25°C and track the formation of products. There was no reaction for a while, but we persevered and at 70°C, we unequivocally identified the production of hydrogen gas and carbon dioxide.” The report has recently been published in the journal Nature Communications.
So, let’s see if we have this straight. Until the discovery of this new process, it took very high heat and lots of energy to get hydrogen and carbon dioxide from formic acid. Now, using far less energy, scientists have found a way to get hydrogen and carbon dioxide from formic acid for less money.
Ummmm, isn’t the purpose of using hydrogen in fuel cells to avoid adding more carbon dioxide to the atmosphere? Professor O’Hair says he and his team are working on that.
Source: Electric Cars Report Image credit: University of Melbourne