Park SJ, Jung WY. Effect of KOH Activation on the Formation of Oxygen Structure in Activated Carbons Synthesized from Polymeric Precursor.
J Colloid Interface Sci 2002;
250:93-8. [PMID:
16290638 DOI:
10.1006/jcis.2002.8309]
[Citation(s) in RCA: 85] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2001] [Accepted: 02/21/2002] [Indexed: 11/22/2022]
Abstract
In this work, the influence of KOH activation on the surface chemistry of activated carbons (ACs) synthesized from polystyrene-based cation exchangeable resin (PSI) has been investigated. The surface chemistry of ACs has been characterized by using Fourier transformed infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), pH measurement, and Boehm's titration method. As a result, PSI can be successfully converted into ACs with high porosities. The total oxygen content on the ACs studied increases with increasing the KOH-to-PSI ratio. FT-IR and XPS analyses show that the resulting carbons possess a number of oxygen surface functional groups, such as carbonyl, quinone, phenol, ether, and carboxylic acid groups. The highest oxygen content and acid value are observed at a KOH-to-PSI ratio of 4 (KPS-4). However, its pH and surface basicity are higher than those of a KOH-to-PSI ratio of 2 (KPS-2), indicating the formation of basic species, such as quinone and pyrone groups. Although the oxygen-containing groups with basic character exist in the resulting carbons, all the samples are still acidic in character.
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