What is the difference between Tar and Bitumen?

Bitumen;

BITUMEN is a petroleum product formed by the process of distillation of crude petroleum. It is available both in solid and liquid form. It is providing a good grip to the tyres as compared to the coal tar. Bitumen is available in three types that is; Rapid Setting, Slow Setting and Medium setting. In the modern era, we used bitumen instead of Coal Tar because Coal Tar is Carcinogenic.

COAL TAR; Coal tar is derived from the coal.It18 is a black viscous liquid used as a sealing agent in old roads making all over the world. It is not used in the current era, due to the carcinogenic product. It is produced through the process of destructive distillation in the absence of air. Coal Tar not provide enough grip to the tyres of the vehicle and heat up quickly causes wearing out of tyres.

1. Tar And Bitumen

• Tar: No longer used for road construction because of its *Carcinogenic Effect and high temperature susceptibility. Presently, roads are mostly constructed using Bitumen.
• Reason For Confusion Between Tar and Bitumen: Both have black color and both have very good Waterproofing and adhesion property.
• Production Method:
  • Tar→ From Destructive Distillation (Burning in Specific Condition of Temperature, Without Presence of Oxygen) of Bituminous Coal
  • Bitumen→ Obtained From Refining Process (Fractional Distillation) of Crude Oil (A Petroleum Product)

* For Manufacturing of Tar, Coal is Burnt Without Presence of Oxygen. This induces formation of specific molecules called Polyclic Aromatic Hydrocarbons [PAH] which are carcinogenic.

(PAH represent 20–30% Composition of Tar. That’s the Reason the Use of Tar is Banned in Most Countries.)

[PAH is also present in Bitumen. But only approximately 0.01%. So, it is not carcinogenic]

Bitumen:

1. Bitumen is naturally occurring substances, it is dark in color & it occurs in both solid and liquid form.

2. Bitumen is a viscous organic substance, which occurs naturally.

3. Bitumen is strongly adhesive and water-resistant. & it is always a viscous liquid.

4. Bitumen is created by distilling crude oil.

5. Bitumen use as a waterproof, sealing agent and in road construction.  It is a good binder.

Tar:

1. Tar is obtained artificially by the process of destructive distillation. It is always in a viscous liquid form.

2. Tar is very thick, it is good water-resistant.

3. Tar widely use in industries.