What are The Differences Between Carbon Black and Graphite?

 

Introduction to Carbon Black and Graphite

 

Carbon Black

Carbon black is an amorphous form of carbon. Light, loose and very fine black powder, with a very large surface area, ranging from 10 to 3000m2/ g, is the product of incomplete combustion or thermal decomposition of carbon-containing substances (coal, natural gas, heavy oil, fuel oil, etc.) under the condition of insufficient air. Specific gravity 1.8-2.1. Those made from natural gas are called "gas black", those made from oil are called "lamp black", and those made from acetylene are called "acetylene black". In addition, there are "trough black" and "furnace black". According to the performance of carbon black, there are "reinforced carbon black", "conductive carbon black", "wear-resistant carbon black", etc., which can be used as black dye.

 

 

Graphite

Graphite, commonly found in metamorphic rocks, is formed through regional metamorphism or magmatic intrusion from coal or carbonaceous rocks (or sediments) [1]. Graphite is an allotrope of elemental carbon, with each carbon atom being surrounded by three other carbon atoms arranged in a honeycomb pattern of hexagons and exhibiting weak van der Waals attractions between layers. Due to the liberation of electrons from each carbon atom, graphite functions as an electrical conductor. It possesses one of the lowest hardness levels among minerals and has an opaque and greasy texture upon touch. Its color varies from iron black to steel gray, manifesting in diverse forms such as crystals, sheets, scales, striations, layers or dispersed within metamorphic rocks. Chemically inert and resistant to corrosion.

 

The Difference of Carbon Black and Graphite

1. Difference in Definition

Carbon Black:

The term "carbon black" refers to a type of amorphous carbon characterized by its lightweight, porous nature, extensive surface area, and exceptionally fine particles. It is produced through the incomplete combustion or thermal decomposition of carbon-based substances such as coal, natural gas, heavy oil, or fuel oil. The adjective "amorphous" denotes its lack of defined shape and absence of regular structural patterns.

Graphite:

Graphite is characterized by a hexagonal layered structure and possesses excellent chemical stability, corrosion resistance, as well as low reactivity towards acids, bases, and other reagents.

 

2. Difference in Structural

Carbon Black:

The structure of carbon black is determined by the extent to which its particles form chains or clusters. It consists of aggregates that exhibit variations in size, morphology, and particle count within each aggregate. This particular type of carbon black is commonly referred to as high-structure carbon black.

Graphite:

Graphite is a layered crystal with transitional properties, bridging the gap between atomic, metallic, and molecular crystals. The interlayer bonding is facilitated by van der Waals forces, while the carbon atoms within each layer form covalent bonds through sp2 hybridization. Each carbon atom forms connections with three neighboring carbon atoms, resulting in the formation of regular hexagonal rings on a single plane. These rings extend to create a lamellar structure.

 

3. Difference in Physicochemical Property

Carbon Black:

When carbon black is pigmented, its darkness primarily results from the absorption of light. The chemical properties of graphite remain relatively stable at room temperature, and only fluorine among halogens can directly react with elemental carbon. Under heating conditions, elemental carbon readily undergoes oxidation by acid. At elevated temperatures, carbon can also form metal carbides through reactions with various metals. Carbon exhibits reducibility and enables the smelting of metals at high temperatures.

Graphite:

The same plane of carbon atoms contains electrons that can freely move within the lattice, leading to graphite's metallic luster and its ability to conduct electricity and heat. Due to the significant interlayer spacing, the van der Waals force binding between layers is weak, facilitating layer sliding. Consequently, graphite exhibits lower density compared to diamond and possesses a soft and lubricious texture. Moreover, the intralayer binding force among carbon atoms is exceptionally strong and extremely resistant to disruption, resulting in graphite's high melting point and stable chemical properties.

 

4. Difference in Electroconductibility

The electrical conductivity of graphitized carbon is exceptional, and its conductivity improves with a higher degree of graphitization. Consequently, graphite generally exhibits superior electrical conductivity compared to carbon black. However, in plastic systems, incorporating a smaller amount of carbon black can yield better conductivity than graphite due to the conductive factor being influenced not only by the inherent conductivity of the added conductive powder but also by the distribution of conductive particles within the polymer matrix. When comparing equal quantities of carbon black and graphite with a lower proportion of carbon black occupying a larger volume fraction in the polymer system, it facilitates the formation of a conductive network and thus achieves enhanced filler conductivity compared to graphite powder. Nevertheless, when highly aggregated, graphite aggregates exhibit significantly superior electrical conductivity than carbon black. This explains why high-quality conductive electrode materials are fabricated using graphite rather than conductive carbon black.

 

5. Difference in Application

Carbon Black:

It is primarily utilized as a reinforcing agent and filler in rubber applications, accounting for approximately 50% of total rubber consumption. Carbon black for rubber constitutes 94% of overall carbon black production, with around 60% being employed in tire manufacturing. Furthermore, it serves as a pigment in inks, coatings, and plastics, while also acting as a UV screening agent for plastic products. Additionally, it plays a crucial role as an additive in various other industries including electrodes, dry batteries, resistors, explosives, cosmetics, and polishing pastes.

Graphite:

Graphite is utilized in the production of refractory materials, conductive materials, wear-resistant materials, lubricants, high-temperature sealing materials, corrosion-resistant materials, thermal insulation materials, adsorption materials, frictional materials and radiation protection materials. These versatile substances find extensive applications in industries such as metallurgy, petrochemicals machinery electronics nuclear technology and national defense.

 

Grinding Mill Recommendation

The particle size of both carbon black and graphite powder needs to be finely processed, which is determined by their respective application fields. Taking carbon black as an example, the reinforcing property becomes stronger as the particle size decreases after grinding. Therefore, Clirik recommends utilizing the third generation HGM ultrafine grinding mill.

 

 

HGM Ultrafine Grinding Mill

Capacity: 0.5-45 t/h

Feed Size: ≤20 mm

Powder Fineness: 325-3000 mesh

The HGM Ultrafine grinding mill (also known as micro powder mill, superfine powder grinding mill, ultra fine powder grinder) has been meticulously designed by Clirik's R&D department through numerous innovations and rigorous testing. It has been unequivocally proven by a multitude of satisfied customers that our ultra fine powder grinder possesses exceptional features, unwavering quality, effortless operation, and maintenance convenience. Undoubtedly, it stands as the quintessential equipment for precision fine powder milling.

 

Working Principle

  

The materials are propelled to the periphery of the rotating plate by centrifugal force and descend into the grinding chambers, where they undergo repeated compression, crushing, and grinding by the rollers.

Subsequently, the materials cascade through multiple layers and continue to be pulverized until they reach a micro powder consistency. The high-pressure air blower continuously draws in air within the fine grinding mill, creating an airflow that carries crushed materials to the classifier. Within this classifier, a high-speed impeller screens the airflow, separating unqualified particles which fall back into the mill for regrinding while qualified particles mixed with air enter into a cyclone powder collector.

The majority of qualified powders exit through the discharging valve at bottom while a small proportion of fine powders accompany airflow to reach a dust cleaner where they adhere to filter bags on its surface. Simultaneously, these adhered fine powders are dislodged due to sudden vibrations caused by instantly ejected high-pressure gas controlled by pulse valves. Both sets of materials mentioned above are conveyed at bottom for packaging finished powders. Additionally, clean filtered air is emitted from an outlet in muffler's end.

 

Mill Advantages

 

1. Enhanced Efficiency With equivalent final size and motor power, the superfine powder grinding mill boasts double the capacity of a jet mill, mixing grinder, or ball mill, while reducing energy consumption by 30%.

 

2. Prolonged Lifespan of Spare Parts The ring and roller are forged from specialized materials with high utilization rates. Under identical grinding material and desired special size conditions, spare parts have a lifespan of approximately one year - two to three times longer than an impact mill or turbo mill. Moreover, when grinding calcite carbonate, their longevity can reach 2-5 years. The lifespan of spare parts varies depending on material hardness.

 

3. Superior Safety and Reliability Due to the absence of rolling bearings or screws in the grinding cavity, issues caused by bolt shedding or rapid wear of bearings and seal components are eliminated.

 

4. Exceptional Fineness and Adjustable Precision The ultimate fineness of ground materials can be flexibly adjusted within the range of 325 meshes to 3000 mesh.

 

5. Advanced Intelligent Speed Control Device Pulse bag filters and mufflers effectively mitigate dust pollution and noise.

 

6. Environmentally Friendly Approach By uniformly feeding material into the machine and adjusting its main speed to better suit ground material characteristics, it enhances capacity efficiency while reducing power consumption.