2. Industrial coal tar processing

The use and valorization of the products obtained after distillation has evolved considerably over time.

In the 19th century, tars were distilled mainly to separate pitch for use as a coating for boat caulking.

During the first half of the twentieth century, tar distillation was perfected to extract a number of aromatic molecules through additional treatments such as physical-chemical extraction, crystallization and rectification, laying the foundations for industrial organic chemistry.