Tuesday 28 October 2014

Special Catalyst or How to Convert Greenhouse Gases into Useful Chemicals

Introduction

Welcome again, dear readers. Today I looked through the modern discoveries in science and found one interesting investigation, published in University of Delaware journal, which was conducted in January 30, 2014. This investigation is about new catalyst that converts greenhouse gas into chemicals. In this post I want to explain the science of this discovery, and to demonstrate its significance for the society and scientific community. By the end of this post you will understand: what is the discovery about, how this innovation works, how this investigation related to chemistry science and why it is important. 

Development of New Catalyst

In January 30, 2014, explorers from the University of Delaware investigated a special catalyst that was able to convert greenhouse gas, which is carbon dioxide (CO2), to carbon monoxide (CO) (see Picture 1). The point is that this catalyst makes the reaction occur with extremely high percentage of efficiency, 92 %.


Picture 1. Converting of Carbon Dioxide (left) to Carbon Monoxide (link)

In fact, this efficiency was achieved by using a selective electrocatalyst that consists of nano-porous silver. In comparison with polycrystalline silver, catalyst that is usually used to convert carbon dioxide into other chemicals, nano-porous silver electrocatalyst is 3000 times more active. The reason of the high activity of new catalyst lies in its structure. Electrocatalyst, discovered by UD (University of Delaware) research group, has inside surface that is very large and extremely curved. This surface is 20 times larger and 20 times more active than polycrystalline silver has.

We have considered the discovery, now let`s discuss this investigation as a chemist. Firstly, this catalyst converts carbon dioxide to carbon monoxide. Actually, this reaction occurs when carbon dioxide is reduced to produce carbon monoxide and oxygen: CO2 --> CO + 1/2 O2

It can be expected that you will ask: what is a catalyst? Catalyst is a compound that increases a chemical reaction, but does not participate in it. It speeds up the reaction by lowering activation energy, energy that is required for the reaction to occur (see Picture 2).

Picture 2. Activation Energy With and Without Catalyst (link)

 

Significance of the New Investigation

The development of new catalyst is very important in different cases. New catalyst converts carbon dioxide to carbon monoxide with extremely high efficiency. As a result, more carbon monoxide is produced. This is very beneficial, because carbon monoxide might be used to elaborate helpful chemicals.

Greenhouse gases have negative impact on the planet, because there are a lot of problems due to them, for example: melting of polar ice caps, impact on weather, damage to agriculture. Therefore, this development is important, because it converts greenhouse gas, carbon dioxide, into carbon monoxide, and decrease the amount of danger greenhouse gases present on the planet.

In conclusion, we discussed the investigation discovered by University of Delaware research group. They investigated a catalyst that converts carbon dioxide into carbon monoxide with 92% efficacy. Even though its mechanism uses very simple chemistry, it is highly significant to society and scientific community. This catalyst increases the production of carbon monoxide that might be used to elaborate useful chemicals. Also, this development converts CO2, greenhouse gas, into CO. So it decreases the amount of greenhouse gases present on the Earth. This is significant because greenhouse gases are very dangerous to our planet. If you want to research more about this discovery, you can use sources listed in the reference list below.


References:

1. Chen, Zuofeng, Javier J. Concepcion, M. Kyle Brennaman, Peng Kang, Michael R. Norris, Paul G. Hoertz, and Thomas J. Meyer. "Splitting CO2 into CO and O2 by a single catalyst." Proceedings of the National Academy of Sciences 109, no. 39 (2012): 15606-15611.
 2. Green Energy. "Greenhouse Gases – The Dangers." Green Energy. http://www.greenenergyhelpfiles.com/articles/17.htm (accessed October 28, 2014).
 3. Hsu, David. "Definition of Catalyst." Chemicool. http://www.chemicool.com/definition/catalyst.html (accessed October 27, 2014).
 4. Lu, Qi, Jonathan Rosen, Yang Zhou, Gregory S. Hutchings, Yannick C. Kimmel, Jingguang G. Chen, and Feng Jiao. "A selective and efficient electrocatalyst for carbon dioxide reduction." Nature communications 5 (2014).
5. Roberts, Karen . "Renewable energy resources." UDaily. http://www.udel.edu/udaily/2014/jan/new-catalyst-013014.html (accessed October 28, 2014).
 

Tuesday 7 October 2014

Upp Hydrogen Fuel Cell: Useless Innovation or Future?

Introduction

Welcome to my blog again, dear readers. Yesterday, I read an article from the Guardian News that was called “Upp hydrogen fuel cell review: get off the grid, but at a price”, published in October 6. This article has considered a device that is called “Upp”. In this post I want to explain this article and provide additional information by conducting extra research. By the end of this post you will know: what is Upp hydrogen fuel cell, how this device works and how this can be evaluated using chemistry knowledge. 

What`s Upp and How It Works?

According to the article, the Upp is a hydrogen fuel cell. But what is a fuel cell? Fuel cell is an electrochemical apparatus that perform a chemical reaction in order to produce electricity. The article states that Upp hydrogen fuel cell liberates electrons which produce a current by rearranging hydrogen into water. This technology is considered as “off-the-grid” charger for electronic devices, which needs only reusable hydrogen fuel receptacle and air to power electronics through a USB port.


Picture 1. Upp Hydrogen Fuel Cell (link)

As stated in the article, the Upp consists of two parts (see Picture 1). First part, shorter one (9 cm), is fuel cartridge. Second part, the main part, is 12 cm long and it contains all electronic components, including cell fuel. In consonance with an article from ZdNet, when these parts are connected to each other by a special magnet, the device is ready to work. If you want to see how it actually works, you can watch the video above.

Video 1. Upp Personal Hydrogen Fuel Cell Hands-on (link)

In the gas state hydrogen is extremely dangerous, due to its high flammability. Therefore, hydrogen in the Upp is in the form of solid metal hydride. This is hydrogen fuel, known as Hydralloy C5, which contains hydrogen combined with titanium, zirconium, vanadium, iron, chromium and manganese. At the end of the article, author concluded that Upp hydrogen fuel cell has high price (£149), £35 for cartridge and £10 to refill it. One cartridge is able to charge no more than 5 smartphones. Also, he enclosed that it is heavy (full weight is 620 gram) and it works very slowly.

We have understood what is the Upp device and how it works. However, I think you want to ask me: is there any connection with chemistry? The answer is yes. Now, let`s look at this case as a chemist. First of all, the Upp technology uses Hydralloy C5 that is protecting storage of hydrogen. However, firstly, hydrogen should be extracted and then stored in this form. Hydrogen is abundant in our planet, but only in the form of chemical compounds, like hydrocarbons or water. And one of the beneficial sources of hydrogen is methane (CH4). Methane decomposes to release carbon (C) and hydrogen (H2).
Picture 2. Production of Water by Combining Hydrogen and Oxygen (link)  

At the start, I mentioned that current is produced when hydrogen is converted into water by combining with air. Actually, the mechanism is slightly different. Hydrogen reacts with oxygen, contained in air, to produce water (see Picture 2). The reaction is explosive, therefore the Upp device uses hydrogen not in a pure form, but in the form of Hydralloy C5.

Decomposition of one mole (unit of measurements in chemistry) of methane requires 90.1 kJ of energy, while production of water from hydrogen releases 232 kJ. Therefore, we can state that this process is beneficial, because we achieve more energy than we spend.

In conclusion, we looked through an article that explained the device that is called “Upp”. It is portable and it needs only air, hydrogen fuel cell and hydrogen itself to work. In the article it was concluded that it is not useful, because it is heavy, expensive and the process of charging is slow. Then, this case was evaluated using chemistry knowledge. Hydrogen for the device is extracted from methane, and then this hydrogen reacts with oxygen to produce water. It was calculated that this process is beneficial, because we get more energy than we give. Therefore, this process may be not so useful in the sphere of portable chargers, but can be very beneficial in generating electricity for other spheres. If you want to know more about the article that was explained or sources that were used, you can see reference list above.

References:

      1. Carcassi, M. N., and F. Fineschi. "Deflagrations of H2–air and CH4–air lean mixtures in a vented multi-compartment environment." Energy 30, no. 8 (2005): 1439-1451. Accessed October 7, 2014. http://www.sciencedirect.com/science/article/pii/S0360544204000532
      2. Choudhary, T.V.. Methane Decomposition: Production of Hydrogen and Carbon Filament. Texas: The Royal Society of Chemistry, 2006. Accessed October 5, 2014.  http://www.chem.tamu.edu/rgroup/goodman/pdf%20files/465_catal_19_06_164.pdf
      3. Gibbs, Samuel. "Upp hydrogen fuel cell review: get off the grid, but at a price." Guardian News (London), October 6, 2014. Accessed October 6, 2014. http://www.theguardian.com/technology/2014/oct/06/upp-hydrogen-fuel-cell-review-off-grid-charger
      4. International Bureau of Weights and Measures, Barry N. Taylor, and Ambler Thompson. The international system of units (SI). US Department of Commerce, Technology Administration, National Institute of Standards and Technology, 2001. Accessed October 7, 2014. http://pml.nist.gov/Pubs/SP330/sp330.pdf
      5. McLellan, Charles. "Upp fuel cell review: Off-grid gadget power, at a price gadget power, at a price." ZDnet (London), June 4, 2014. Accessed October 5, 2014. http://www.zdnet.com/upp-fuel-cell-review-off-grid-gadget-power-at-a-price-7000030214/
      6. Miessler, Gary L., and Donald A. Tarr. Inorganic chemistry. 3rd ed. Upper Saddle River, N.J.: Pearson Education, 2004. Acessed October 6, 2014. http://www.mediafire.com/download/rav02sav4yazvzw/%5BeBook%5D+Inorganic+Chemistry_Pearson-Miessler+%26+Tarr-3rd+edition.pdf
      7. Pohlmann, Carsten, Lars Röntzsch, Felix Heubner, Thomas Weißgärber, and Bernd Kieback. "Solid-state hydrogen storage in Hydralloy–graphite composites." Journal of Power Sources 231 (2013): 97-105. Accessed October 7, 2014. http://www.sciencedirect.com/science/article/pii/S0378775312018903
      8. Porcja, Bob. "Explosive Reaction of Hydrogen and Oxygen Using Balloons." Rutgers Chemistry Lecture Demonstration (CLD) Facility. Accessed October 6, 2014. http://cldfacility.rutgers.edu/content/explosive-reaction-hydrogen-and-oxygen-using-balloons
      9. Smithsonian Institution. "Fuel Cell Basics." A Basic Overview of Fuel Cell Technology. Accessed October 5, 2014. http://americanhistory.si.edu/fuelcells/basics.htm
      10. University of California. "The Future of Methane." Future Energy Use. Accessed October 5, 2014. http://earthguide.ucsd.edu/virtualmuseum/climatechange2/11_3.shtml