The new system opens up the transition to CO2's production fuel


Carbon dioxide ball and stick model. Credit: Wikipedia

Think of the day when the atmosphere is backward – gases from power plants and heavy industries are instead captured and catalyzed catalytic reactors that chemically transform greenhouse gases such as carbon dioxide into industrial fuel or chemicals and just oxygen.


This is the future that Hottian Vang says is that many are much closer.

In the Roland Institute of Holvard, along with Vang and colleagues, developed an improved system for the use of renewable electricity to reduce carbon monoxide carbon monoxide – the main goods used during major industrial processes. The system is described on paper published on November 8 Julie, A newly opened sister magazine of the mobile press.

"The most promising idea can be to connect these devices with coal-fired power plants or other industries that carry many codes2, – said Vang, "About 20 percent of these gases are CO2So if you can pump this pump … Clean power combination, then we can potentially use useful chemicals from these wastes to sustainable way and this CO2 Cycle ".

The new system, Wang said, represents a dramatic step ahead of one and his colleagues first described in the 2017 paper Chem.

Where the old system was hardly mobile phone size and relied on the two chambers filled with electrolytes, each of which was electrodes, the new system is cheaper and relies on high concentrations of CO2 More efficient operation of gas and water steam – only 10-inch 10-inch cells, says Vanagi, could produce four liters of CO per hour.

The new system, Wang said, will address two major challenges in the cost and scalability that are considered as limiting the approach from.

"In this early work we discovered one nickel atom catalyst that was very selective for the reduction of CO2 CO … But one challenge faced that the materials were expensive to synthesize, "said Vang," We used to support one-time nickel atoms based on Grapefen, wanting to imagine a gram or a kilogram throughout the future for practical use. "

To solve this problem, he said, his team became a commercial product that is thousands of hours cheaper than alcoholic beverages alternative.

Such process of electrostatic attraction, volatile and colleagues can absorb single nickel atoms (positively charged) into defective carbon black nanoparticles (positively charged), resulting in low and high selection of CO2 Decrease.

"Right now, we can best describe the gram, but we could only have one picture of the billions before," Vang said. "But this is only limited by the synthesis apparatus if you have a bigger tank, you can have a kilogram or even a ton of catalyst."

The second challenge Wang and colleagues had to overcome were tied to the fact that the original system only worked with a liquid solution.

The original system worked in one of the wards to divide water molecules into oxygen and protons using electrodes. As oxygen hampers, protons transmit through the liquid solutions in the second ward, where with the help of nickel catalyst they are CO2 And the molecule has died, leaving CO and water. This water soon switched to the First Chamber where it would be split again and the process would start again.

"The problem was that CO2 We can reduce this system only in water. Most of the molecules around the catalyst were water, "he said," only traces of paper CO2, So it was quite ineffective. "

Although it may be tempting to simply increase the voltage used catalyst to increase the reaction rate that may have unforeseen resulting dividing water, no reduction in CO2, – said Vang.

"If you hang on the CO2 This is near the electrode, other molecules need to be expanded and it takes time, "said Van, but if the voltage is increased, the adjacent water will get the opportunity to react and split hydrogen and oxygen."

The solution was relatively simple to avoid dividing the water, the team received a catalyst solution.

"We have replaced liquid water with water steam and fill in high concentrations of CO2 Gas, "he said," so if the old system had more than 99% water and less than 1% of CO2, Now we can completely revise that and pump 97 percent CO2 Gas and just 3% water vapor in this system. This liquid water also functions in the system of ionic conductors, and now we use ion exchange membranes instead to help ions move without liquid water.

"The impact is that we can supply a high power density by order," he continued. "Earlier, we worked around ten miles per square centimeter, but today we can easily divide 100 million.

Going forward, Vang says that the system still has to overcome challenges, especially stability.

"If you want to use this economic or ecological impact, it must have thousands of hours of continuous operation," he said. "Now, we can do dozens of hours so it's still a huge gap, but I believe these problems can be addressed to a more detailed analysis of both CO2 Reduce catalyst and water oxidizing catalyst. "

Ultimately, Wang said today can come when the industry will be able to capture CO2 Which is now transformed into an atmosphere and transformed into a useful product.

"Carbon monoxide is not a particularly high value chemical product," Wang said. "To explore more opportunities, my group has also developed several copper-based catalysts that will further reduce CO2 Into much more valuable products.

Wang used it for the freedom of the Rowdale Institute to promote the new system.

"Rowland gave me as an early career researcher, a great platform for independent research that starts with a large part of research in the direction my group will continue to push forward," said Wang, who recently took a position in Rice at the University. "I will definitely miss my days here".


Learn further:
Carbonizing the carbon: The system can move CO2 to CO2 for use in the industry

Journal Reference:
Julie

Provided by:
Harvard University