Main-Product

Pitch is a black or dark brown viscoelastic residue obtained by distillation of coal tar, petroleum fractions, wood tar, or other organic materials. It consists of a complex mixture of predominantly aromatic hydrocarbons and heterocyclic compounds, exhibiting a broad softening range rather than a defined melting point.

Pitch is technically a highly viscous fluid that appears solid at room temperature and can shatter with hard impact, but flows extremely slowly over time. This viscoelastic behavior distinguishes pitch from true solids.​

Sources and Types

Pitch is obtained from three main sources:

• Coal tar pitch: Soft to hard brittle substance rich in polycyclic aromatic hydrocarbons (PAHs), aromatic resinous compounds, and their derivatives. Contains highly aromatic structures with minimal aliphatic substitution.

• Petroleum pitch: Derived from thermal processing of aromatic petroleum fractions. Characterized by lower aromaticity, substantial aliphatic substituents on aromatic rings, higher molecular weight, and presence of naphthene rings absent in coal tar pitch. Contains significantly lower carcinogenic PAH content than coal tar pitch.

• Wood tar pitch (rosin): Bright, lustrous substance containing resin acids derived from plant sources.​

Terminology

While "tar" and "pitch" are sometimes used interchangeably, tar generally refers to more liquid products from destructive distillation, whereas pitch specifically designates the semi-solid to solid residue remaining after tar distillation. Petroleum-derived pitch may also be called bitumen or asphalt, though these terms have broader meanings.