Author Archives: nat shipp

Turning CO2 back into fuel

Typically, when you burn a hydrocarbon fuel, you get waste products like CO2, a serious greenhouse gas. But what if we could turn CO2 back into fuel? A research team at Oak Ridge National Laboratory in Tennessee has made a breakthrough: they found a simple method to do just that. By embedding copper into nanospikes, they were able to make a powerful electrocatalyst that works something like many tiny lightning rods, which concentrate an electric field. This is able to turn CO2 into ethanol.

The reaction starts by reducing CO2 to carbon monoxide, CO. Then two CO molecules connect to form a dimer with the two carbon atoms bonded to each other. Finally, this dimer is reduced, removing an oxygen atom and gains hydrogen atoms. Although they initially believed this process would produce methanol, the final product is actually ethanol.

The structure of ethanol.

The structure of ethanol. This public domain image is from https://commons.wikimedia.org/wiki/File:Ethanol-2D-flat.png.

The process is fairly efficient, but not efficient enough to use on an industrial scale yet. The electrons have a yield of 63 percent, meaning only 27 percent of electrons will be “lost” during the reaction, mostly being taken up by hydrogen. The CO2 has a yield of 84 percent. The energy efficiency is not as good, only around 20 percent. On the positive side, the process only needs common materials, such as carbon, nitrogen, copper, and CO2.

It is hoped that this process will someday help reduce CO2 added to the atmosphere. Since it uses CO2 as a reagent, it would only add about as much to the atmosphere as it removes. The reaction could even work as efficient, clean energy storage – excess energy from renewable sources could be used to convert CO2 into ethanol, storing it as chemical energy for later use. However, it is still in development and has a long ways to go before it’s ready for large-scale use.

~ Nat Shipp

 

Sources:

Popular Mechanics – Meet the scientists turning CO2 into ethanol

Discover – Nanospikes Convert Carbon Dioxide Back Into Ethanol

Oak Ridge National Laboratory – Nano-spike catalysts convert carbon dioxide directly into ethanol

SciShow – Using Devil’s Milk to kill superbugs

 

Montreal Protocol amendment limits hydrofluorocarbon manufacture

In 1987, after the hole in the ozone layer was discovered over Antarctica, an international treaty called the Montreal Protocol was agreed to. This treaty basically ended chlorofluorocarbon (CFC) manufacture all over the globe. CFCs were widely-used refrigerants used in refrigerators and air conditioning. CFCs were replaced by hydrofluorocarbons (HFCs). This treaty was a success – a couple of years ago, the ozone layer was clearly showing signs of recovering. However, since 1987 it has been found that while it varies from chemical to chemical, HFCs as a whole tend to be just as bad as CFCs. This is why, a few days ago in Rwanda, delegates from the 197 countries involved in the treaty agreed to an amendment that aims to cut down on HFC production.

An example of a CFC an an HFC.

An example of a CFC an an HFC. HFCs contain hydrogen instead of chlorine. Both are gases used as refrigerants, and are greenhouse gases and harmful to the ozone layer.
This public domain image is courtesy of Wikimedia and the original can be found at https://commons.wikimedia.org/wiki/File:CFC-12_HFC-134a(catal%C3%A0).svg

According to this new agreement, the richest countries such as the US, Canada, and the EU countries are required to begin cutting down by 2019, developing countries such as China and Latin American countries begin in 2024, and some of the poorest countries such as Pakistan and Iran do not need to begin until 2028. However, China and India already say they will actually begin phasing out HFCs later than they agreed to in the treaty. India doesn’t have widespread use of air conditioning or refrigeration, but China produces the most HFCs in the world.

Experts estimated that this treaty will lessen atmospheric CO2 by 70 billion tons by 2050 – this may not be enough to reduce global warming by 0.5 degrees as hoped, but it is no small feat. It must have been hard for 197 nations to come to an agreement, although I’m a little disappointed it took them seven years of negotiation to do it. Overall, though, I think this is pretty exciting.

~ Nat Shipp

 

Sources:

BBC – “Climate Change: ‘Monumental’ deal to cut HFCs, fastest growing greenhouse gases”

Euronews – “‘Historic’ climate change deal reached in Rwanda”

Business Standard – “Global deal on climate-changing refrigeration gases sealed in Rwanda”

Bits of Science – “Transition from CFCs to HFCs under Montreal Protocol hurts climate – adjustment required”

BBC – “Ozone layer showing ‘signs of recovery,’ UN says”

 

UBC Researcher Developing Marijuana Breathalyzer

Earlier this year at UBC Okanagan’s Advanced Thermo-Fluidic Laboratory, engineering professor Mina Hoorfar and PhD student Mohammad Paknahad developed a breathalyzer for tetrahydrocannabinol (THC), the active ingredient in marijuana. While attempting to make an affordable miniature gas chromatography-mass spectrometry (GC-MS) device, it occurred to them that, with marijuana becoming legalized in more parts of the world every year, there was a growing market they could to tap into. When testing out their device as a THC detector was a success, they started to develop their device specifically as a marijuana breathalyzer.

Unlike traditional breathalyzers, this device utilizes GC-MS and a computer, and is therefore highly adaptable – it can easily be used to search for concentrations of a variety of chemicals. Some other uses they’ve thought of for the device include analyzing the characteristics of wine, checking your own blood alcohol content, monitoring glucose levels in diabetic people, and finding gas leaks along pipelines.

Gas Chromatography-Mass Spectrometry schematic, courtesy of Wikimedia

Gas Chromatography-Mass Spectrometry schematic, courtesy of Wikimedia (https://upload.wikimedia.org/wikipedia/commons/b/b9/Gcms_schematic.gif) Gas is injected into the column, where it sorts itself into groups based on properties such as polarity and molecule size. The groups of molecules pass through the mass spectrometer, which analyzes how much of each chemical there is.

Mina Hoorfar specializes in microfluidics, the field of manipulating tiny amounts of gas and liquid using their chemical properties. In this device, the exhaled breath is channeled through a column that is only one micrometer thick, where the chemical components are separated by their properties and analyzed using the same processes as in regular GC-MS. The results are then sent via Bluetooth to a computer or smartphone, showing the user exactly what is in their breath. The device would cost about $15 to build – incredibly cheap for a GC-MS device, which often cost thousands of dollars – and Hoorfar says that she is working with a lab instrument company to bring the device to the market.

~ Nat Shipp