Bitumen: Types, Applications, and Comparisons with Tar

What Is Bitumen?

The bitumen is the binding material that is present in asphalt. It also sometimes called mineral tar. It is obtained by partial distillation of crude petroleum. It is chemically a hydro-carbon. It is insoluble in water, but it completely dissolves in carbon disulfide chloroform, alkalies, alkaline, carbonates, petroleum spirit, and oil of turpentine.

It is found on analysis is composed of 87 percent carbon 11 percent and 2 percent oxygen by weight. The bitumen is back or brown in colour, and it is obtained is solid or semi-solid or sate. Its applications are the same as the residual asphalt.

Type of Bitumen

Following are the types of Bitumen

1. Blown Bitumen.
2. Cutback Bitumen.
3. Straight Run Bitumen.
4. Penetration Grade.
5. Bitumen Emulsion.
6. Residual Bitumen.

#1. Blow Bitumen:

Soft bitumen can be modified by heating until it becomes a liquid and then passing air under pressure by which all the volatile compounds in it can be driven out. The product is called blown bitumen.

#2. Cutback Bitumen:

Bitumen combined with other petroleum distillates forms cutback bitumen. This may be regarded as a means of applying penetration-grade bitumen at lower temperatures.

#3. Straight Run Bitumen:

When bitumen distilled to a definite viscosity of penetration, which does not require further treatment like heating.

#4. Penetration Grade:

The basic form of bitumen and has to be heated before application.

#5. Bitumen Emulsion:

A product in liquid form, formed in aqueous medium and stabilizing agents. This also another means to obtain bitumen into a liquid form so that it can be easily applied at ambient temperature.

#6. Residual Bitumen:

It consists of bitumen thinner and suitable filler made into a plastic Conn. As it is plastic, it can be used for filling cracks in masonry, stopping leakages, etc.

Use of Bitumen

1. Bitumen is used for the manufacture of roofing and damp proofing felts.
2. For sealing accumulators and batteries.
3. It also used for heat insulation materials for building, refrigeration, and cold storage.

What Is Tar?

Tar is a viscous black liquid made of hydrocarbons that can form in multiple ways. Because of this, the chemical composition of tar varies, though it is always made of organic matter of some sort. It has many uses as a waterproofing and sealing agent. It is also used for many medicinal purposes.

Classified of Tar 

Tat is classified on the basis of its sources.

1. Coal Tar.
2. Mineral Tar.
3. Wood Tar.

#1. Coal Tar:

A heavy, back, and strong-smelling liquid is known as coal tar. In closed iron vessels, the variety of tar is prepared by heating the coal. The escaping gases are allowed to pass through the tube, which is kept cool by the circulation of water.

The coal tax gets deposited in these tubes. It is usually derived as a byproduct during the manufacture of coal gas. The coal tar is used for making macadam roads, preserving timber, etc.

#2. Mineral Tar:

Distillation of bituminous shales gives us mineral tar. It contains less matter.

#3. Wood Tar:

Distillation of pipes and resinous wood gives wood tar. In contains, creosote oil which can be obtained by further distillation of wood and hence is possessed stronger preservation property.However, the wood creosote is not so good as coal tar creosote for the preservation of timber.

Use of Tar :

For coating of sleepers, wooden poles, latrine walls, etc.

Bitumen Vs. Tar

FAQs about Bitumen and Tar

What is bitumen?

Bitumen is a binding material present in asphalt, also known as mineral tar. It is obtained by the partial distillation of crude petroleum and is chemically a hydrocarbon. It is insoluble in water but dissolves in various solvents like carbon disulfide and chloroform.

What is the chemical composition of bitumen?

Bitumen is composed of approximately 87% carbon, 11% hydrogen, and 2% oxygen by weight. It is typically black or brown and can be found in solid or semi-solid states.

What are the types of bitumen?

The main types of bitumen include:

1. Blown Bitumen
2. Cutback Bitumen
3. Straight Run Bitumen
4. Penetration Grade
5. Bitumen Emulsion
6. Residual Bitumen

What is blown bitumen?

Blown bitumen is produced by heating soft bitumen until it becomes liquid and then passing air through it under pressure to remove volatile compounds. The result is a modified bitumen with different properties.

What is cutback bitumen?

Cutback bitumen is bitumen combined with other petroleum distillates, allowing it to be applied at lower temperatures. It is a way to use penetration-grade bitumen more efficiently.

What are the uses of bitumen?

Bitumen is used in roofing, damp proofing, sealing accumulators and batteries, and as heat insulation material for buildings, refrigeration, and cold storage.

What is tar?

Tar is a viscous black liquid made of hydrocarbons, varying in chemical composition. It can be formed from different organic sources and is used as a waterproofing and sealing agent, among other applications.

How is tar classified?

Tar is classified based on its source:

1. Coal Tar
2. Mineral Tar
3. Wood Tar

What is coal tar?

Coal tar is a heavy, black, strong-smelling liquid produced by heating coal in closed iron vessels. It is typically a byproduct of coal gas

What is mineral tar?

Mineral tar is obtained from the distillation of bituminous shales and contains fewer volatile compounds compared to other types of tar.

What is wood tar?

Wood tar is produced by the distillation of resinous wood. It contains creosote oil, which has preservation properties, although wood creosote is not as effective as coal tar creosote for timber preservation.

What are the uses of tar?

Tar is used for coating sleepers, wooden poles, latrine walls, and various waterproofing applications.

What are the main differences between bitumen and tar?

Key differences include:

1. Bitumen is deep dark, while tar is jet black.
2. Bitumen has moderate carbon content; tar has very high carbon content.
3. Bitumen is usually solid; tar is a viscous liquid.
4. Bitumen melts upon heating; tar becomes more fluid.
5. Bitumen sets quickly; tar sets slowly.
6. Bitumen is less toxic and more resistant to weathering and acids than tar.
7. Bitumen is obtained from crude oil distillation; tar is obtained from destructive distillation of coal or wood.
8. Bitumen is more adhesive but less toxic than tar.
9. Bitumen is more expensive than tar.

Which is more commonly used for road construction, bitumen or tar?

Bitumen is more commonly used for road construction due to its better resistance to weathering and lower toxicity compared to tar.

Can bitumen be used for waterproofing?

Yes, bitumen is widely used for waterproofing applications, including roofing and damp proofing felts.

What is the viscosity of bitumen compared to tar?

Bitumen has a lower viscosity compared to tar, making it easier to handle and apply in various construction applications.