Fuel from diamonds?
Futuristic fuels could replace our current supplies, recycling what the latter’s combustion produces most: carbon dioxide. And synthetic diamond exposed to light may hold the key
18 October 2017
Nothing is lost, nothing is created, everything is transformed. The principle underlying modern chemistry seems to support efforts by scientists to fight CO2 emissions.
European researchers are investigating new possible approaches to decrease the concentration of carbon dioxide in the atmosphere, with a view to exploiting them. If successful, the experimental technology will help fight climate change and provide a more sustainable supply of raw materials for certain industrial branches.
The vision is to produce useful chemicals from the carbon dioxide treated in water or in other green solvents, with the aid of sunlight. The resulting substances could be used to get fuels for cars, or obtain other compounds such as methanol, formic acid or methane, necessary to the chemical industry that, right now, relies on petroleum or natural gas.
“That would help use less fossil sources and recycle carbon dioxide closing, in a way, the circle,” says Anke Krueger from the Institute for Organic Chemistry of Julius-Maximilians University in Wuerzburg, Germany. She coordinates the DIACAT project (Diamond materials for the photocatalytic conversion of CO2 to fine chemicals and fuels using visible light), which is part of the EU Future and Emerging Technologies (FET) programme.
The milestone of the whole process is synthetic diamond, a very resistant material produced artificially. When the electrons are excited during a chemical reaction inside the diamond, they get high levels of energy and transform CO2 into fine chemicals.
This solution can be seen as a man-made alternative to the photosynthesis of plants, which reintroduce carbon dioxide into the biochemical cycle. Only the photocatalytic system is different.
The ingredients needed in the lab experiment are: solvent, which works as a medium, synthetic diamond, the active material, and carbon dioxide as a study material. Light is used to excite electrons in the diamond, sparking a reaction with carbon dioxide.
Neither of the compounds that go into this reaction is detrimental to the environment, Krueger assures: “We don’t use dangerous materials to make this process, we use water or ionic liquids for the solvent. And diamond material itself is not toxic. The carbon dioxide is anyway the exhaust gas from cars, power stations or cements plants, constantly emitted by transportation and industry, so removing that from air is beneficial, rather than problematic.”
“If this technology is utilised on a large-scale, the side effects of the carbon dioxide, namely the production of the greenhouse gas effects, can also be reduced. At the moment, we are at the laboratory scale, so the carbon dioxide consumption is very small, but the goal is to use as much carbon dioxide as possible to produce something useful out if it,” explains Krueger. She underlined that the scientific team is not targeting other toxic gases in the atmosphere for the time being.
By the end of the project (the finish line is mid-2019) a demonstrator lab device will be ready to produce C1 building blocks, which are basic substances from CO2, to show that the whole process is running properly and to allow the collection of the stability data. Later, large enterprises could be involved, and a technologically more advanced demonstrator could be used at the industrial scale.
By Sorina Buzatu