Thursday, February 16, 2023

Scientists Use Nano Carbons To Convert Methane Into Hydrogen

  • Scientists at the University of Surrey discovered metal-free catalysts that could contribute to cost-effective and sustainable hydrogen production technologies.

  • The study has shown promising results for the use of edge-decorated nano carbons as metal-free catalysts for the direct conversion of methane into hydrogen.

  • When it comes to storing hydrogen methane is a good choice, nature had that figured out hundreds of millions of years ago.

University of Surrey researchers have found that a type of metal-free catalysts could contribute to the development of cost-effective and sustainable hydrogen production technologies.

The results entitled ‘First-Principles Microkinetic Modeling Unraveling the Performance of Edge-Decorated Nanocarbons for Hydrogen Production from Methane’ have been published at ACS Applied Materials & Interfaces.

The study has shown promising results for the use of edge-decorated nano carbons as metal-free catalysts for the direct conversion of methane, which is also a powerful greenhouse gas, into hydrogen. Among the nano carbons investigated, nitrogen-doped nano carbons presented the highest level of performance for hydrogen production at high temperatures.

Crucially, the researchers also found that the nitrogen-doped and phosphorus-doped nano carbons had strong resistance to carbon poisoning, which is a common issue with catalysts in this process.

Dr Neubi Xavier Jr, the research fellow who performed the material science simulations, said, “Our results suggest that using edge-decorated nano carbons as catalysts could be a game-changer for the hydrogen industry, offering a cost-effective and sustainable alternative to traditional metal catalysts. At the same time, this process gets rid of methane, which is a fossil fuel involved in global warming.”

Hydrogen fuel is a clean and renewable energy source that has the potential to reduce carbon emissions and decrease our dependence on fossil fuels. When used as a fuel, hydrogen can power vehicles, generate electricity, and heat buildings. The only by-product of hydrogen fuel is water vapor, making it an environmentally friendly alternative to traditional fossil fuels.

However, the production of hydrogen fuel is currently reliant on fossil fuels, which creates carbon emissions in the process, and metal catalysts, which mining and manufacturing are energy intensive and can negatively affect the environment. Therefore, the development of sustainable hydrogen production methods and catalytic materials is crucial to realizing the full potential of hydrogen fuel as a clean energy source.

The research was conducted by a team led by Dr Marco Sacchi from the University of Surrey, an expert in the field of sustainable energy and computational chemistry, who combined quantum chemistry, thermodynamics and chemical kinetics to determine the most efficient edge decoration for hydrogen production.

Dr Sacchi said, “One of the biggest challenges with catalysts for hydrogen production is that they can get poisoned by carbon. But our study found that nitrogen and phosphorus-doped nano carbons are pretty resistant to this problem. This is a huge step forward for sustainable hydrogen production.”

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While it is a bad thing to be venting methane out into the atmosphere, methane is a great store of energy and produces more heat and light energy by mass than other hydrocarbons. That could be because methane is one carbon atom and four hydrogen atoms.

When it comes to storing hydrogen methane is a good choice. Nature had that figured out hundreds of millions of years ago.

What’s not said in the press release is where those carbon atoms end up. There seem to be choices in the study paper. For now lets say the CH2CH2 ethylene double bound molecules as a chemical (there is quite a large worldwide market for ethylene) would need remade into something(s) civilization or nature can use to their benefit. For now, answers like carbon monoxide for industrial processes or carbon dioxide for plant sustainability won’t go with the hysterical anti carbon crowd. The next step looks critical for the process to find true usefulness. The next step could prove to be a driver of the process.

On the other hand, this information could be an alternative to the current tech of extracting the hydrogen from methane. That tech is still the low cost leader for making hydrogen fuel. It will be interesting to see how this progresses over the coming years.

Scientists Successfully Split Seawater To Produce Green Hydrogen

  • A team of scientists have successfully split natural seawater without pre-treatment to produce green hydrogen. 

  • The team will work on scaling up the system by using a larger electrolyzer so that it can be used in commercial processes such as hydrogen generation for fuel cells and ammonia synthesis.

  • Seawater is an almost infinite resource and is considered a natural feedstock electrolyte.

University of Adelaide’s Professor Shizhang Qiao and Associate Professor Yao Zheng from the School of Chemical Engineering led an international team that successfully split seawater without pre-treatment to produce green hydrogen.

Professor Qiao said, “We have split natural seawater into oxygen and hydrogen with nearly 100 per cent efficiency, to produce green hydrogen by electrolysis, using a non-precious and cheap catalyst in a commercial electrolyser.”

The team published their research in the journal Nature Energy.

A typical non-precious catalyst is cobalt oxide with chromium oxide on its surface.

Associate Professor Zheng explained, “We used seawater as a feedstock without the need for any pre-treatment processes like reverse osmosis desolation, purification, or alkalization. The performance of a commercial electrolyser with our catalysts running in seawater is close to the performance of platinum/iridium catalysts running in a feedstock of highly purified deionized water.

Professor Zheng added, “Current electrolysers are operated with highly purified water electrolyte. Increased demand for hydrogen to partially or totally replace energy generated by fossil fuels will significantly increase scarcity of increasingly limited freshwater resources.”

Seawater is an almost infinite resource and is considered a natural feedstock electrolyte. This is more practical for regions with long coastlines and abundant sunlight. However, it isn’t practical for regions where seawater is scarce.

Seawater electrolysis is still in early development compared with pure water electrolysis because of electrode side reactions, and corrosion arising from the complexities of using seawater.

“It is always necessary to treat impure water to a level of water purity for conventional electrolysers including desalination and deionization, which increases the operation and maintenance cost of the processes,” noted Zheng. “Our work provides a solution to directly utilize seawater without pre-treatment systems and alkali addition, which shows similar performance as that of existing metal-based mature pure water electrolyser.”

The team will work on scaling up the system by using a larger electrolyzer so that it can be used in commercial processes such as hydrogen generation for fuel cells and ammonia synthesis.

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Should this work get replication with similar success it will be a breakthrough. No expensive precious metals involved. But cobalt while not so rare isn’t abundant by any means and is often sourced from ore gathering by small children. That makes the future of cobalt very much up in the air for assessment. Should this research prove up, the cobalt demands would sky rocket and get way more expensive. There is cobalt to be had, its just buried under ‘not in my backyard’ and the environmental green groups’ lawyer barriers, which plug up the politics quite severely.

The second matter is that the power source isn’t discussed. While the energy input is definitely electric and the claim is near 100% efficiency, the input vs product calculation isn’t shown or discussed.

Yet the prospect of a greatly reduced water source cost, plus not using precious metals is cause for a lot of anticipation. Congratulations to the team is in order. Lets hope the next steps are solvable by low costs and not requiring decades of political maneuvering to get the jobs done.

By Brian Westenhaus via New Energy and Fuel

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