<p style="text-align: justify"><img class="alignright" style="border: 2px solid black" alt="CO2 Tanks" src="http://farm7.staticflickr.com/6205/6077870033_66f7dd6094_q.jpg" width="150" height="150" /></p>
<p>One of the major environmental causes undertaken by researchers is the issue of the increased concentration of carbon dioxide (CO?) in the air.</p>
<p>CO? is one of the main greenhouse gases, and a leading instigator in global warming.</p>
<p>The high levels of CO? are largely as a result of burning fossil fuels such as coal and petrol.</p>
<p>An interesting technological development could ironically see a fuel, rather than simply emitting CO2,</p>
<p>actually pulling CO? out of the air while being manufactured.</p>
<h2><strong>Titanium Nanotubes</strong></h2>
<p>The application of nanotube technology in the energy industry has been known for some time now.</p>
<p>A nanotube is a cylinder made up of atomic particles with whose diameter is a few billionths of a metre (or nanometres).</p>
<p>They’re stronger than steel, but more flexible than plastic.</p>
<p>They have a variety of uses because they exhibit excellent thermal and electrical conductivity.</p>
<p>Carbon-based nanotubes are the most popularly used nanotubes at this time, but also gaining attention now are titanium oxide nanotubes.</p>
<p>Scientists have used titanium oxide nanotubes, together with sunlight, to transform CO? back into methane,</p>
<p>the main ingredient in natural gas. This can be used as fuel that burns cleaner than other fossil fuels, such as petroleum or coal.</p>
<p>So, on one hand, this could reduce the quantity of CO? in the atmosphere, and on the other hand, provide an alternative, cleaner fuel.</p>
<p>Working on this project is Craig Grimes of Pennsylvania State University, who says, “Right now there is lots of talk about burying carbon dioxide, which is ridiculous.</p>
<p>Instead we can collect the waste out of the smoke stack, put it though a converter, and presto, use sunlight to change [CO?] back into fuel.”</p>
<h2><strong>How it actually works</strong></h2>
<p>The chemical conversion of water and carbon dioxide to methane is easy enough to understand:</p>
<p>one carbon dioxide molecule and two water molecules become one methane molecule and two oxygen molecules.</p>
<p>The team of researchers accomplish this by making an arrangement of titanium oxide nanotubes vertically in the shape of a honeycomb,</p>
<p>which is then covered with a thin layer of copper oxide.</p>
<p>When sunlight is in contact with these two substances, which act as catalysts, carbon is released from the CO? and hydrogen is released from the water molecules.</p>
<p>The released carbon and hydrogen combine to form burnable methane, with oxygen as a by-product.</p>
<h2><strong>A new kind of solar power?</strong></h2>
<p>Sunlight seems to be the way to go.</p>
<p>Using outdoor, visible light, they reported a yield of methane that was 20 times higher than previous attempts conducted in laboratory conditions using intense ultraviolet exposures instead.</p>
<p>Craig Grimes calculates that focusing the light collected from 1,100 square feet onto one of these nanotube membranes could produce over 132 gallons of methane on a sunny day.</p>
<p>Grimes thinks of this process as being analogous to solar power, because essentially energy is being generated via sunlight.</p>
<p>Instead of storing electrons in batteries, energy is stored chemically.</p>
<p>This makes for a clean and sustainable energy source, as the main ingredients are sunlight and water.</p>
<p>So let’s hope that this technology becomes commercially used in the near-future.</p>
<h5>Featured images:</h5>
<p><span class="license">License: Creative Commons</span></p>
<p><span class="source">image source</span></p>
<p>Queenie Bates is an avid reader and writer, especially in the field of sustainable energy.</p>
<p>She tries to stay up to date on new technologies by attending gas events and oil conferences, and reading up on as much as she can.</p>

New Technology Turns CO2 Back Into Fuel
