Tjäror

Tjäror is a term that generally refers to viscous, dark, and sticky substances that are byproducts of the destructive distillation of organic materials, most commonly wood or coal. These substances are complex mixtures of hydrocarbons and other organic compounds, with their exact composition varying significantly depending on the source material and the processing conditions. Historically, tar has been a valuable commodity, used for its waterproofing and preservative properties.

Wood tar, often referred to as Stockholm tar, was historically produced by heating wood in the absence of air. This process yields a dark, pungent liquid that was widely used to treat wooden ships, ropes, and tools to protect them from decay and moisture. It also found applications in traditional medicine and as a fuel. Coal tar, on the other hand, is a byproduct of the coking process in the steel industry, where coal is heated to produce coke. Coal tar is a much more complex mixture than wood tar and is a significant source of various aromatic compounds, many of which are valuable precursors for the chemical industry.

The industrial importance of coal tar has led to the development of sophisticated processes for its fractional distillation, separating it into numerous useful components such as benzene, toluene, xylene, naphthalene, and phenols. These chemicals are fundamental building blocks for a vast array of products, including plastics, dyes, pharmaceuticals, and pesticides. While the direct use of tar for waterproofing has diminished with the advent of modern synthetic materials, its derivatives remain crucial in many industrial sectors. Concerns about the environmental impact and potential health hazards associated with tar and its constituents have also led to stricter regulations regarding their production, handling, and disposal.