Increased chemisorption onto activated carbon after ball-milling

N. J. Welham; V. Berbenni; P. G. Chapman

doi:10.1016/S0008-6223(02)00123-9

Increased chemisorption onto activated carbon after ball-milling

N. J. Welham^*, V. Berbenni, P. G. Chapman

^*Corresponding author for this work

Research output: Contribution to journal › Article › peer-review

52 Citations (Scopus)

Abstract

Activated carbon has been milled for up to 1000 h in a laboratory-scale tumbling ball mill under a vacuum. Thermogravimetric (TG) analysis of the powder in argon showed an increasing mass loss with milling time indicating the presence of chemisorbed gas. TG Fourier transform infrared spectrometry showed the gas was a mixture of water, CO₂ and an unidentified gas (probably oxygen). BET surface area measurements showed a decreasing surface area with milling time, however, this was shown to be massively in error for the longer milling times due to the presence of the chemisorbed gas. The area occupied by the chemisorbed gas increased from 40 to 80% of the true surface area which was almost constant at 1258±27 m² g^-1 for all three powders. These results show that extremely large errors may be made when using BET analysis to determine the surface area of powders, especially those where the surface activity is substantially increased during processing.

Original language	English
Pages (from-to)	2307-2315
Number of pages	9
Journal	Carbon
Volume	40
Issue number	13
DOIs	https://doi.org/10.1016/S0008-6223(02)00123-9
Publication status	Published - 2002

Access to Document

10.1016/S0008-6223(02)00123-9

Cite this

@article{4a12f1b8a01e4e9cab6bdebd31d48c5c,

title = "Increased chemisorption onto activated carbon after ball-milling",

abstract = "Activated carbon has been milled for up to 1000 h in a laboratory-scale tumbling ball mill under a vacuum. Thermogravimetric (TG) analysis of the powder in argon showed an increasing mass loss with milling time indicating the presence of chemisorbed gas. TG Fourier transform infrared spectrometry showed the gas was a mixture of water, CO2 and an unidentified gas (probably oxygen). BET surface area measurements showed a decreasing surface area with milling time, however, this was shown to be massively in error for the longer milling times due to the presence of the chemisorbed gas. The area occupied by the chemisorbed gas increased from 40 to 80% of the true surface area which was almost constant at 1258±27 m2 g-1 for all three powders. These results show that extremely large errors may be made when using BET analysis to determine the surface area of powders, especially those where the surface activity is substantially increased during processing.",

keywords = "A. Activated carbon, B. Grinding, C. Thermal analysis (DTA and TGA), BET surface area, D. Adsorption properties",

author = "Welham, {N. J.} and V. Berbenni and Chapman, {P. G.}",

year = "2002",

doi = "10.1016/S0008-6223(02)00123-9",

language = "English",

volume = "40",

pages = "2307--2315",

journal = "Carbon",

issn = "0008-6223",

publisher = "Elsevier Ltd.",

number = "13",

}

TY - JOUR

T1 - Increased chemisorption onto activated carbon after ball-milling

AU - Welham, N. J.

AU - Berbenni, V.

AU - Chapman, P. G.

PY - 2002

Y1 - 2002

N2 - Activated carbon has been milled for up to 1000 h in a laboratory-scale tumbling ball mill under a vacuum. Thermogravimetric (TG) analysis of the powder in argon showed an increasing mass loss with milling time indicating the presence of chemisorbed gas. TG Fourier transform infrared spectrometry showed the gas was a mixture of water, CO2 and an unidentified gas (probably oxygen). BET surface area measurements showed a decreasing surface area with milling time, however, this was shown to be massively in error for the longer milling times due to the presence of the chemisorbed gas. The area occupied by the chemisorbed gas increased from 40 to 80% of the true surface area which was almost constant at 1258±27 m2 g-1 for all three powders. These results show that extremely large errors may be made when using BET analysis to determine the surface area of powders, especially those where the surface activity is substantially increased during processing.

AB - Activated carbon has been milled for up to 1000 h in a laboratory-scale tumbling ball mill under a vacuum. Thermogravimetric (TG) analysis of the powder in argon showed an increasing mass loss with milling time indicating the presence of chemisorbed gas. TG Fourier transform infrared spectrometry showed the gas was a mixture of water, CO2 and an unidentified gas (probably oxygen). BET surface area measurements showed a decreasing surface area with milling time, however, this was shown to be massively in error for the longer milling times due to the presence of the chemisorbed gas. The area occupied by the chemisorbed gas increased from 40 to 80% of the true surface area which was almost constant at 1258±27 m2 g-1 for all three powders. These results show that extremely large errors may be made when using BET analysis to determine the surface area of powders, especially those where the surface activity is substantially increased during processing.

KW - A. Activated carbon

KW - B. Grinding

KW - C. Thermal analysis (DTA and TGA), BET surface area

KW - D. Adsorption properties

UR - http://www.scopus.com/inward/record.url?scp=0036042288&partnerID=8YFLogxK

U2 - 10.1016/S0008-6223(02)00123-9

DO - 10.1016/S0008-6223(02)00123-9

M3 - Article

SN - 0008-6223

VL - 40

SP - 2307

EP - 2315

JO - Carbon

JF - Carbon

IS - 13

ER -

Increased chemisorption onto activated carbon after ball-milling

Abstract

Access to Document

Other files and links

Fingerprint

Cite this