My last post on commercial algae production mentioned the importance of CO2. Without additional CO2 - in densities greater than what's found in the atmosphere - algae farms would not be commercially viable.

There may be another way to get energy from CO2. The Max Planck Institute has developed a catalyst that breaks the stable CO2 bond much like algae and other plants.

In photosynthesis, the CO2 molecule is initially bonded to nitrogen atoms, making reactive compounds called carbamates. These less stable compounds can then be broken down, allowing the carbon to be used in the synthesis of other plant products, such as sugars and proteins.

In an attempt to emulate this natural process, Goettmann and colleagues Arne Thomas and Markus Antonietti developed their own nitrogen-based catalyst that can produce carbamates. The graphite-like compound is made from flat layers of carbon and nitrogen atoms arranged in hexagons.

The team heated a mixture of CO2 and benzene with the catalyst to a temperature of 150 ºC, at about three times atmospheric pressure. In a first step, the catalyst enabled the CO2 to form a reactive carbamate, like that made in plants.

The catalyst's next useful step was to enable the benzene molecules to grab the oxygen atom from the CO2 in the carbamate, producing phenol and a reactive carbon monoxide (CO) species.

From there it is relatively easy to refine fuel. When oil supplies were limited during World War II, Nazi Germany made fuel from carbon monoxide derived from coal.

Now these researchers are attempting to further increase efficiency by using light as the energy source to split CO2 - again, like plants.

It seems that one way or another, excess CO2 will be less a problem than a solution.