Pennsylvania State University researchers found out a way to transform the messy CO2 from the atmosphere into burnable gas, with the help of the Sun. They made use of nanotechnology for this matter, and their results showed a 20 times yield, compared to other findings.
The research led by Craig Grimes, used a photocatalyst to react with the light, and the most proper one was titanium dioxide, or titania.
Several experiments have been made in the past using titania, but with no interesting results, despite the researchers’ struggles in experimenting with various forms, such as nanoparticles, pellets, and multi-film layers.
Craig Grimes used 140 micrometers-long and 115 nanometers-wide titania nanotubes, and enriched them with nitrogen particles. To increase their output even more, they scattered an ultra-thin platinum layer and/or copper, using as “cocatalyst” nanoparticles on the array’s surface.
Their final product has 2 square centimeters, with several samples created for the purpose of experimentation.
Here’s how they experimented: they made two reaction chambers, provided with a window at their top, to let in sunlight. After loading one sample into each of the chambers, they created a vacuum, and sealed them. Next, the researchers pumped CO2 through a water tank (probably using this method to humidify the CO2, flushing it through the intake and outtake valves for 10 minutes.
After leaving the samples 2.5 to 3.5 hours in full sunlight, they analyzed the the chambers’ interiors, and revealed high amounts of methane. Other gases were ethane, propane, butane, pentane, hexane, and others in very small concentrations. Comparing to previous alike experiments, Grimes concluded that the rate of hydrocarbon production rate was 20 times higher, and thought that a homogeneous distribution of the two catalysts (titania and copper) could increase the results even more.
Now, the following problem arises: if we convert CO2 into methane and burn it again, don’t we get the same amount of CO2 back? We’re not gaining anything from here, except maybe for the process of producing titanium dioxide, that may also produce CO2 on the way (if you know exact numbers, please comment). On the other hand, the good thing is that we’re recycling even the all-feared CO2.
This is a process similar to one featured in a story called “Storing Sunshine in a Can”, which was a popular mechanics (I think?) article from 6 or 8 years ago. The story went on about how Israel is using a process to convert sunlight, methane, and superheated steam (from the sun, hence the title) into a CO2 and hydrogen mixture that was stable and easy to transport. When the process is reversed, the mixture produces methane and superheated steam to drive turbines. 100% eco-friendly as the only produced material is water (the methane is captured and reused). I just wonder if the process was ever used? I guess it’s derived from a german WWII discovery, but the process itself is facinating.
Regarding the ‘recycling of CO2’ as described so well in your article, is that not what is being proposed for algae fuels? If I’m not mistaken, algae craves sunlight, sugars and CO2. Provided sufficient quantities of these, it multiplies quickly. Then we burn it, releasing the CO2. But the carbon balance isn’t that bad, certainly better than corn-ethanol…
Similarly, Carbon Science, Inc. in Santa Barbara claims to have figured out how to turn CO2 into gasoline fuels using microorganisms convert CO2 into hydrocarbons, will be recycling existing CO2, not creating new.
Cheers, Chris