Porosity and surface area of carbon black

✍ Scribed by Jaspard H. Atkins

• Publisher: Elsevier Science
• Year: 1965
• Tongue: English
• Weight: 370 KB
• Volume: 3
• Category: Article
• ISSN: 0008-6223
• DOI: 10.1016/0008-6223(65)90064-3

✦ Synopsis

This is a critical evatuation of the B.E.T. and Cumulative Surface Area techniques for measuring specific surface areas. The Cumulative Surface Area technique which calculates the surface areas for different pore size increments which can be displayed as a histogram is described briefly and the results obtained for different carbon blacks are discussed.

With graphitized MPC carbon black which contains no pores of less than 20 A diameter, the agreement between the two techniques is good. With MPC which has some pores between 10 and 20 A, the nitrogen B,E.T. value is higher, but if the isotherm is corrected for nitrogen condensed in small pores, the recalculated BET.

value agrees with the Cumulative Surface Area value. With samples having some pores less than 10 A diameter, which is the case for most air-oxidized biacks, the agreement is poor.

The nitrogen B.&T. area is higher than the true value, and the Cumulative Surface Area is lower. This statement is supported by additional B.E.T. areas using neopentane, a large gas molecule, as the adsorbate.