In great news for conspiracy theorists everywhere, the next major monetary policy introduced by the governments around the world could be laundering money – literally. Researchers Nabil M. Lawandy and Andrei Smuk have identified a cleaning technique using “supercritical” CO2 that could save billions of dollars and reduce the environmental impact that would otherwise result from destroying and reprinting 150 billion worn and dirty banknotes worldwide.
The research, outlined in a paper published in the ACS journal Industrial & Engineering Chemistry Research, demonstrates that the major culprit behind notes being pulled from circulation prematurely is the oil our skin produces to protect itself. Known as sebum, this oil oxidizes and causes notes to yellow. Another reason to make sure you handle your banknote collection carefully!
One way to make the notes last longer, and therefore reduce the financial and environmental cost of destroying, reprinting and reissuing the notes is to clean them, but this has a few challenges of its own. The most important issue is that many traditional cleaning methods also damage sensitive security features used in notes worldwide, such as phosphorescent ink and holograms.
The researchers solved that particular conundrum by turning to “supercritical” CO2, a substance that behaves like both a gas and a liquid when brought to the right temperature and pressure. It has commonly been used in other cleaning applications, such as environmentally friendly dry cleaning and – would you believe it – the production of decaffeinated coffee.
There is no doubt that this is potentially a fantastic money-saving process that could also help the environment and should be of interest to major note printing authorities around the world.
On the whole, this is a clever idea that could, if you will pardon the pun, save the government a lot of money. Time will tell if it ever goes in to practice.