Gujarat Technological University

L.D. College of Engineering

Year: 2016-17Subject: Chemical Process Industries (2130505)

Topic : Manufacturing of Carbon Black

Name of the Student:Jaydrath Sindhav (160283105011)

History of Carbon Black

The first commercial nano-material. Carbon black was called "soot" in the west and "shouen" in the east.

In the 1740's, plant production started in the United States, and because of the production method used, it was then called “lampblack.”

The term "carbon black" originated in the 1870's, when products manufactured from natural gas were sold under this name and since then the name prevails.

An allotrope of carbon, mainly differing from graphite and so-called amorphous carbon by its physical arrangement

Used since more than 5000 years in pigmentation Found its major development with automobile and more specifically the tyre industry as rubber reinforcing agent.

Carbon black properties

Physicochemical properties 1. Particle size : This refers to the size of an individual particle of carbon black, the

smaller the particle size the larger the specific surface. 2. Structure : This shows the state of particles adhered to others of similar size and

also indicates oil absorption. The greater the oil absorption, the more complex the configuration.

3. Surface characteristic : Various functional groups are combined on the surface of carbon black, by modifying the surface properties, we can change the compound characteristics.

4. Aggregate distribution : The size of the aggregates (individual carbon black particles fused to other particles of a similar size) varies.If the distribution is sharp, this indicates that there are many aggregates of the same size.

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1. Reinforcement : Carbon black is added to the rubber used in tire treads, to high-pressure hoses, and has other demanding applications, as well as added to plastics as material reinforcement.

2. Conductivity : Conductive carbon black is added to natural rubber or other materials to decrease their electrical resistance. For example: the conductivity of natural rubber is 1015Ωcm, whereas the conductivity of conductive rubber (natural rubber + conductive carbon black) is between 1-1015Ωcm. It is believed that this characteristic is the result of the structure of carbon black particles contacting each other which forms conductive channels of electrons jumping between dispersed carbon black particles.

3. Pigmentation : Carbon black has strong tint properties, it is heat stable and suitable for plastic and film colouring. This property is believed to result from the particle size and the structure's interaction with light.

4. Preventive properties against ultraviolet degradation : Carbon black's absorption of ultraviolet light is excellent. Adding carbon black to other materials prevents ultraviolet degradation.

Carbon black common Uses

1. Rubber reinforcement : Carbon black is a rubber-reinforcing additive used in a multitude of rubber products. In particular, in case of vehicles, large amounts of carbon black are used for tires. In addition, carbon black is used with rubber to dampen earthquake vibration, in the soles of shoes and in many other products.

2. Colours and pigments for plastics : Compared with other colorants, carbon black has a high colouring power. Therefore. it is used as ink for printing newspapers, as ink-jet toner, and other such uses. It is also suitable as a pigment for heat-molded plastics, car fenders, coating for electric wires and other products.

3. Electric equipment and conductive components : Since carbon black has excellent conductive properties, it is used as a component for magnetic tapes and semiconductors.

Carbon black manufacturing process

Carbon black is produced by combusting oil or gas with a great deal of oxygen inside large furnaces. The furnace walls lined with bricks become very hot because the oxygen and oil combust.

By varying the amount of oil and air, the internal temperature of the furnace can be altered, which permits manipulation of the particle size and particle connections of the carbon black being produced.

The time required to produce carbon black from oil is so short that it cannot be confirmed by the human eye

Classification of carbon black manufacturing processesManufacturing process Raw material Manufacturing method Explanation

Incomplete combustion

Aromatic hydrocarbon oil Oil furnace This is currently the most common method

Mineral/vegetable oils Lampblack Oldest industrial method

Natural gas

Channel Flames contact the lower surface of a channel (an H-shaped steel beam)

Gas furnace Useful for fine-particle carbon black

Thermal decomposition

Acetylene Acetylene decomposition As this is a heat-generation reaction, continuous production is possible

Natural gas ThermalCombustion and thermal

decomposition are repeated in cycles

Classification of carbon black manufacturing procees

Oil furnace method

he furnace method is a carbon black production method that uses continual thermal decomposition of feedstock using heat generated by the combustion of fuel and air.

To resist high temperatures, a special reaction section is lined with a heat-resistant material. Hot air and fuel (oil) are introduced into this section to undergo complete combustion, which elevates the temperature to 1300 degrees.

When a high-temperature atmosphere is formed, feedstock oil is continuously atomized for thermal decomposition.

High-temperature gas with carbon black formed downstream of the reactor is atomized with water to quickly lower its temperature to 1000 degrees, which stops the reaction.

The time between carbon black formation and the end of the reaction is extremely short—generally around a few milliseconds to 2 seconds.

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During this short reaction process, adjustments made to the reactor shape and manufacturing conditions—such as the reactor's temperature and reaction time—make possible the manufacture of carbon black with different particle sizes and structures (particle bonds).

Lampblack method

This method has been used since ancient times and consists of heating resin from trees to produce carbon black. In Europe, this method was used until the middle of the 1930's, when it was replaced by the furnace method.

Lampblack manufacturing equipment consists of a metallic plate to place the raw material, and a cover with a heat-resistant lining for collection. Between the metallic plate and the cover, there is a space into which air can penetrate. Adjusting the amount of air controls the carbon black quality. Radiant heat from the cover vaporizes the raw material and produces partial combustion, resulting in carbon black.

Channel Process

This method forms carbon black by bringing partially combusted fuel, which is generated with natural gas as raw material, into contact with channel steel (H-shaped steel) and then collecting the carbon black which results.

There are yield and environment issues around this method, and therefore has lost the leading role as the mass production process to the furnace process. This method, however, provides carbon black with many functional groups on the surface, being used in some painting applications.

Acetylene Black Process & Gas Furnace Process Acetylene Black Process This process obtains carbon black by thermally decomposing acetylene gas. It provides

carbon black with higher structures and higher crystallinity, and is mainly used for electric conductive agents.

Furnace Black Process This method forms carbon black by blowing petroleum oil or coal oil as raw material

(feedstock oil) into high-temperature gases to combust them partially. This method is suitable for mass production due to its high yield, and allows wide control over its properties such as particle size or structure. This is currently the most common method used for manufacturing carbon black for various applications from rubber reinforcement to colouring.

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