Scientists use microwave oven to turn coal into graphite


In a microwave oven, sparks are generated inside a glass vial containing charcoal powder and copper foil. The result is polycrystalline graphite. (Image courtesy of the University of Wyoming).

This “one-step method with metal-assisted microwave processing” is a new approach which they believe could represent a simple and relatively inexpensive coal conversion technology to make good use of the coal from the Powder River Basin of the Wyoming.

According to the team led by TeYu Chien at the University of Wyoming, while previous research has shown that microwaves can be used to reduce the moisture content of coal and remove sulfur and other minerals, most of these methods require a specific chemical pretreatment of the carbon. In their experience, however, the only treatment performed was to grind the raw coal from the Powder River Basin into powder.

This powder was then placed on a sheet of copper and sealed in glass containers with a gas mixture of argon and hydrogen, before being placed in a microwave oven.

“By cutting the copper foil in the shape of a fork, sparks were induced by the microwave radiation, generating an extremely high temperature of over 1,800 degrees Fahrenheit within seconds,” said Chris Masi, lead author of the article, in a press release. .

The high temperatures then transformed the carbon powder into polycrystalline graphite, with the copper foil and hydrogen gas also contributing to the process.

The group – which also includes researchers from New York, Nepal and China – believes this new method of converting coal could be refined and carried out on a larger scale to produce both higher quality and quantity of nano material. -graphite.

Source link