Carbon Dioxide is often at the epicenter of all our environmental dialogues. Perhaps, the most convenient villain for all its popularity. But ask many to name some more greenhouse gases and most of us will come up short.

Their are far more dangerous villains out there, and one of them is chlorofluorocarbons. Known ubiquitously as CFC. Over the last few decades, a rising tide of environmental activism took CFCs off the grid. Long used as refrigerants, they were banned in the 1990's because of their tendency to damage the ozone layer. A victory of sorts in the first round of the environmental wars. Unfortunately, many compounds of similar ilk still find their way into the atmosphere. They might not have entered our collective consciousness but it doesn't make them any less dangerous.



One such is fluorocarbons. The absence of a chlorine molecule doesn't offset the danger as they are powerful greenhouse gasses in their own right. They are major components of many products ranging from Teflon cookware (there chemical structure is water-phobic) to artificial blood (they have high oxygen solubility).

Here's a fact to digest - A fluorocarbon, tetrafluoromethane is 6,500 times as potent a greenhouse gas as CO2. Once released into the atmosphere it can hang on in the atmosphere for 50,000 years. And this is where the problem starts as their unreactive nature makes them difficult to clean up from the atmosphere. Earlier proposed methods to clean up fluorocarbons rely on collecting and storing the chemical rather than converting it into safer forms. But their inactivity essentially means that they would have to stored for eternity.

Oleg Ozerov at Brandeis University in Waltham, Massachusetts and his team have been working on the problem for long. Their efforts have focused on a chemical neutralization process. As he says,
"If it's at all economically feasible, it would be better to put the fluorocarbons through a chemical transition rather than store them."
Earlier, they narrowed down their research to a class of chemical compounds called ‘Lewis Acids'. What these compounds do is to basically break the inert bonds that make up fluorocarbons. The problem they had encountered in their initial attempts was how to sustain the reaction for a length of time as the acid had a strong tendency to react with other elements too. The search was for a class of Lewis acids that could sustain itself through the entire duration of the chemical reaction with the targeted fluorocarbons.

The answer came in the form of a Lewis Acid discovered by Christopher Reed and his team at the University of California. Their version of the Lewis acid contains the element silylium (a reactive form of silicon) and a reagent, triethylsilane. Silylium is the aggressor which rips apart the fluorocarbon bonds while triethylsilane is the protector, coming in afterwards to tame and tidy up the highly reactive compounds produced.
Oleg Ozerov says that the reaction is a ‘downhill’ process; using very little energy and the end products leave very little impact on the atmosphere.

Granted that the experiment is still at the laboratory stage and for efficient real world success it needs to graduate up, but environmental safety withstanding some 'heroic' chemicals could be just the scourge for the 'villainous' ones.

Source: NewScientist.com
Image:Flickr.com