American chemists from the National Chemical Association have developed new and effective methods for disposing of electronic waste – a technique that cannot be recycled by classical methods.
A typical recycling process involves the use of a large number of similar products made from a single material that can be converted either into valuable raw materials or even finished products. For electronics, such a traditional method does not work, since radio engineering, computer and other devices contain too many small parts made from various materials with very different properties. It is not possible to separate the components using classic more or less cheap technologies used by recyclable materials.
At the same time, electronic waste is of significant value – it contains a high content of non-ferrous metals and other elements in demand. After analyzing the situation, the American Chemical Association has developed complex mechanisms that combine the preliminary calibration of waste and its subsequent processing at strictly defined temperatures. This made it possible to obtain composite materials from electronic waste with useful properties.
Following the developed algorithms, the researchers turned a mixture of glass and plastic into a valuable ceramic containing silica. They also used a calibration and selective heating process to extract copper, which is widely used in electronics, including printed circuit boards.
Further, by studying the properties of various copper and silica compounds, a team of experts led by Veena Sahajwalla and Rumana Hossain found that, after extracting them from e-waste, these materials could be used to create a new, durable hybrid coating suitable for protection metal surfaces.
To create and then apply the hybrid material to steel, the scientists first heated glass and plastic powder from old computer monitors to 2,732 ° F, creating silicon carbide nanowires. They then positioned the resulting nanowire, along with circuit boards, on a steel substrate and reheated it to 1832 ° F, which caused the copper to melt to form a silicon carbide-rich hybrid layer over the steel.
Subsequent testing showed that the hybrid layer is firmly attached to the steel, without cracks or chips. This not only protects the metal from corrosion, but also increases its surface hardness by 125%.
Scientists called the developed process of creating and applying a hybrid protective coating “waste microsurgery” and believe that it opens a new direction in the processing of electronic waste, which can be used profitably without the use of additional expensive raw materials.