The key difference between carbon black and activated carbon is that the surface-area-to-volume ratio of carbon black is lower than that of activated carbon.
Both carbon black and activated carbon are important materials as adsorbing agents. They have a high surface area compared to their volume, which allows the substance to absorb as much as it can. We call them paracrystalline carbon compounds.
CONTENTS
1. Overview and Key Difference
2. What is Carbon Black
3. What is Activated Carbon
4. Side by Side Comparison – Carbon Black vs Activated Carbon in Tabular Form
5. Summary
What is Carbon Black?
Carbon black is an adsorbing agent that forms from the incomplete combustion of heavy petroleum products. There are a few subtypes of carbon black, including acetylene black, channel black, furnace black, lamp black, and thermal black. The heavy petroleum products that can be used as sources for the production of carbon black are FCC tar, coal tar, ethylene cracking tar, etc. Anyhow, this material should not be confused with soot.
Figure 01: Carbon Black
Carbon black contains only carbon atoms. It appears as a black powder. Practically, this powder is insoluble in water. The molar mass of carbon black is 12 g/mol. All types of carbon black have chemisorbed oxygen complexes. E.g. carboxylic, quinonic, lactonic, etc. These complexes are on the surface of carbon black particles. Depending on the conditions and manufacturing steps, the degree of these complexes on particle surface differs. These surface compounds are considered as volatile species. Besides, carbon black is a non-conductive material due to its volatile content.
Moreover, there are many applications of carbon black. It is mainly an important reinforcing material. It is used as a reinforcing filler for tires and other rubber products. In addition, it is used as a colour pigment in paint, plastics, ink, etc. The carbon black that has a vegetable origin are useful as food colouring agents.
What is Activated Carbon?
Activated carbon is an adsorbing agent that is derived from charcoal. Therefore, it is also called an activated or active charcoal. This material is made of carbon atoms and it has a very high surface-area-to-volume ratio. It contains low volume pores that increase the surface area of the substance, allowing it to adsorb materials as much as it can.
Figure 02: Activated Carbon
There are many uses of activated carbon. It is useful in methane and hydrogen gas storage, air purification due to its adsorption ability, solvent recovery, decaffeination, gold purification, metal extraction, treating poisoning and overdose conditions, stationary phase for chromatographic separation techniques, etc.
What is the Difference Between Carbon Black and Activated Carbon?
The key difference between carbon black and activated carbon is that the surface-area-to-volume ratio of carbon black is lower than that of activated carbon. We call them paracrystalline carbon compounds. Besides, carbon black is produced from incomplete combustion of heavy petroleum products while activated carbon is produced from charcoal.
Below infographic summarizes the difference between carbon black and activated carbon.
Summary – Carbon Black vs Activated Carbon
Both carbon black and activated carbon are important as adsorbing agents. The key difference between carbon black and activated carbon is that the surface-area-to-volume ratio of carbon black is lower than that of activated carbon. We call them as paracrystalline carbon compounds.
Reference:
1. “Carbon Black.” Carbon Black – an Overview | ScienceDirect Topics, Available here.
2. “Carbon Black.” Wikipedia, Wikimedia Foundation, 16 Dec. 2019, Available here.
3. “Activated Carbon.” Wikipedia, Wikimedia Foundation, 6 Mar. 2020, Available here.
Image Courtesy:
1. “Carbon black” By FK1954 – Own work, Public Domain) via Commons Wikimedia
2. “Activated Carbon” By Self (en:User:Ravedave) – Self (en:User:Ravedave) (CC BY 2.5) via Commons Wikimedia