träkul

Trækul is the Danish word for charcoal. It is a carbonaceous material produced by heating wood in a low-oxygen environment, a process called pyrolysis. This process removes water and volatile compounds, leaving behind a residue that is primarily carbon. Trækul has been used by humans for millennia for various purposes due to its combustibility and ability to absorb impurities.

Historically, trækul was a crucial fuel source for metallurgy, enabling the smelting of iron and other metals. Its high carbon content and relatively clean burn made it superior to raw wood for these high-temperature applications. It was also used in pottery kilns and for heating homes. In modern times, while still used as a fuel, particularly for grilling and barbecues, its applications have expanded.

Trækul is also employed as an adsorbent. Its porous structure allows it to trap and hold molecules from liquids or gases. This property makes it valuable in water purification, air filtration, and even in some medical applications, such as treating poisoning. Activated trækul, a form of träkul that has undergone further processing to increase its porosity, is particularly effective as an adsorbent. The production of trækul can be done through various methods, ranging from traditional earth kilns to more sophisticated industrial retorts. The type of wood used and the pyrolysis conditions influence the properties of the resulting träkul.