An environmentally friendly process holds the promise of producing pure graphene in large quantities using food waste, plastic and other materials
[Translation by Dr. Nachmani Moshe]
Scientists use high-energy beams of electricity to convert any carbon-containing source into crystalline graphene in an instant. The process ensures environmental benefits through the conversion of waste into the valuable material graphene that can be used to reinforce concrete and add to other composite materials. These products could significantly reduce the environmental impact of cement and other construction materials.
An innovative process developed in the chemistry laboratory of researcher James Tour at Rice University makes it possible to convert significant amounts of any carbon source into flakes of the valuable material graphene. The process is fast and cheap; The lead researcher says: "The 'graphene flash' method can convert a ton of coal, food waste or plastic into graphene at a fraction of the price of other methods of producing graphene in large quantities." "These are important findings," says the lead researcher. "Humanity throws away between thirty and forty percent of all food produced, since the food spoils, and in addition - plastic waste is becoming a worldwide concern. We have already proven that any solid carbon-based material, including mixed plastic waste and rubber tires, can be converted into graphene."
As published in the prestigious scientific journal Nature, 'flash graphene' is obtained within ten milliseconds by heating carbon-containing materials to a temperature of 5000 degrees Celsius. The source material can be almost any carbon-containing material - food waste, plastic, petroleum coke, coal, wood shavings are the main candidates, says the researcher. "In view of the expensive current commercial price of graphene which is between 67 and 200 thousand dollars per ton, the implications of this innovative process are important," said the researcher. The researcher explains that a minimal concentration of even 0.1% of flash graphene in the cement used to hold the cement in a stable form could reduce its environmental impact threefold. Cement production annually emits about eight percent of all man-made carbon dioxide.
"By strengthening the cement by incorporating graphene, we will be able to use less cement for construction, and thus production and transportation inputs will decrease." "Ultimately, we capture greenhouse gases such as carbon dioxide and methane that would otherwise be emitted by the food waste into landfills in the ground. We convert these carbon materials into graphene and then combine the graphene with other materials, such as cement, thereby reducing the amount of carbon dioxide produced in cement production. This use of graphene is a clear environmental advantage."
"Converting waste into a valuable material is a central element in the field of 'circular economy'," said one of the researchers. "In our case, the graphene is used both as a two-dimensional template and as a reinforcing material that controls the hydration phase of the cement, and ultimately the development of its strength."
In the past, explains the lead researcher, "graphene was too expensive to use in such applications. The flash process will significantly reduce the price and, in addition, will help in more correct management of waste." "With the help of our process, this carbon undergoes fixation," said the researcher. "He will not return to the air again in the vicinity."
The graphene flash process will be able to convert solid carbon into graphene for use in cement, asphalt, construction materials, vehicles, clothing and other fields, the researcher notes. The flash process takes place in a mat specially designed for this purpose, where the material is quickly heated and all the carbonaceous elements are emitted as gas. "When this process becomes industrialized, elements such as oxygen and nitrogen emitted from the flashback will be able to be captured as valuable small molecules." The lead researcher claims that the flash process produces a small amount of excess heat, channeling most of its energy to the required purpose. "All the excess energy is emitted as light, in the form of a very bright flash, and since the process is solvent-free, it is an extremely clean process." The lead researcher hopes to reach within two years of research a situation where one kilogram of flash graphene can be produced every day.
More of the topic in Hayadan:
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Sorry, don't know Graphene. I only know graphite and graphene. Even a Google search for the mysterious graphene did not bring up any alternative except graphene, it is graphene. What remains is of course graphite, which is a loose collection of (two-dimensional) layers of graphene, and it can be burned and turned into simple and massive CO2 (and all the layers of graphene from which it is composed). Indeed, Google claims that graphene burns and combines with oxygen at a temperature of 350 degrees C.
Regarding the natural decomposition of graphene, I don't know, but they are working on graphene that will be biodegradable (for medical applications). In any case, I wouldn't want the cable of the space elevator to just wear out like that in the middle of life.
A very small torch and a Greta Thunberg roast could have been my second name, although I don't think that's really a relevant answer. I think the plastic can also be cut with a torch. The question is whether it is necessary to drop from a hundred km/h to absolute zero in one energetic flash or is it better to follow the path of all flesh and rot in biochemical processes for a good few years? I don't know what the right answer is. I just wanted to comment that what requires 5000 degrees in its creation, may need high energies in its destruction.
Lab Tortoise (great name), in cement making processes reach 1200-1300 degrees
to the big green hopper,
Although graphite and graphene are very similar (graphene is a single layer of graphite) they have very different properties. And so, graphene is not a fancy way of saying graphite.
to the big green hopper,
Although graphene and graphene are very similar (graphene is a single layer of graphene) they have very different properties. And so, graphene is not a fancy way of saying graphite.
Assuming that what is written in the article and the video is true, then one permil of graphene in cement saves 35% of the amount of cement required. That is, a ratio of 1:350 in the amount of material that needs to be heated to a very high temperature.
Although the graphene is heated to a temperature of 5000 degrees Celsius, but also the cement, in the process of its preparation, is heated to a very high temperature, I think over 1,000 degrees Celsius.
Not bad at all.
Crystalline graphene? Isn't that a fancy way of just saying, "graphite"?
And one more thing, I couldn't figure out what all the mysterious "carbon elements" are that are emitted from the electric flash. How many carbon elements are there anyway?
And Ami Bacher, rest your mind, it seems to me that if you put a torch close to this graphene, it will simply turn into shriveled CO2, rise into the atmosphere and save Greta Thunberg within 12 years. Of course, they will need a very small torch for this, because the quantities they manage to produce today are minimal.
And what breaks down the graph? This is again the problem of plastic in the world, which piles up and piles up and there is nothing to break it down. If it takes 5000 degrees to make graphene, what is needed to break it down? We may still bury our carbon in a way that does not allow it to return to the cycle.