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Title: Adsorption of hydrogen sulfide onto activated carbon fibers: effect of pore structure and surface chemistry

Abstract

To understand the nature of H{sub 2}S adsorption onto carbon surfaces under dry and anoxic conditions, the effects of carbon pore structure and surface chemistry were studied using activated carbon fibers (ACFs) with different pore structures and surface areas. Surface pretreatments, including oxidation and heat treatment, were conducted before adsorption/desorption tests in a fixed-bed reactor. Raw ACFs with higher surface area showed greater adsorption and retention of sulfur, and heat treatment further enhanced adsorption and retention of sulfur. The retained amount of hydrogen sulfide correlated well with the amount of basic functional groups on the carbon surface, while the desorbed amount reflected the effect of pore structure. Temperature-programmed desorption (TPD) and thermal gravimetric analysis (TGA) showed that the retained sulfurous compounds were strongly bonded to the carbon surface. In addition, surface chemistry of the sorbent might determine the predominant form of adsorbate on the surface. 38 refs., 7 figs., 3 tabs.

Authors:
; ; ;  [1]
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  1. University of Pittsburgh, Pittsburgh, PA (United States). Department of Civil and Environmental Engineering
Publication Date:
OSTI Identifier:
20700939
Resource Type:
Journal Article
Resource Relation:
Journal Name: Environmental Science and Technology; Journal Volume: 39; Journal Issue: 24; Other Information: vidic@pitt.edu
Country of Publication:
United States
Language:
English
Subject:
54 ENVIRONMENTAL SCIENCES; HYDROGEN SULFIDES; ACTIVATED CARBON; CARBON FIBERS; PORE STRUCTURE; SURFACE PROPERTIES; SURFACE AREA; OXIDATION; SORPTIVE PROPERTIES; ADSORPTION; RETENTION; HEAT TREATMENTS

Citation Formats

Wenguo Feng, Seokjoon Kwon, Eric Borguet, and Radisav Vidic. Adsorption of hydrogen sulfide onto activated carbon fibers: effect of pore structure and surface chemistry. United States: N. p., 2005. Web. doi:10.1021/es0507158.
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Wenguo Feng, Seokjoon Kwon, Eric Borguet, & Radisav Vidic. Adsorption of hydrogen sulfide onto activated carbon fibers: effect of pore structure and surface chemistry. United States. doi:10.1021/es0507158.
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Wenguo Feng, Seokjoon Kwon, Eric Borguet, and Radisav Vidic. Thu . "Adsorption of hydrogen sulfide onto activated carbon fibers: effect of pore structure and surface chemistry". United States. doi:10.1021/es0507158.
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@article{osti_20700939,
title = {Adsorption of hydrogen sulfide onto activated carbon fibers: effect of pore structure and surface chemistry},
author = {Wenguo Feng and Seokjoon Kwon and Eric Borguet and Radisav Vidic},
abstractNote = {To understand the nature of H{sub 2}S adsorption onto carbon surfaces under dry and anoxic conditions, the effects of carbon pore structure and surface chemistry were studied using activated carbon fibers (ACFs) with different pore structures and surface areas. Surface pretreatments, including oxidation and heat treatment, were conducted before adsorption/desorption tests in a fixed-bed reactor. Raw ACFs with higher surface area showed greater adsorption and retention of sulfur, and heat treatment further enhanced adsorption and retention of sulfur. The retained amount of hydrogen sulfide correlated well with the amount of basic functional groups on the carbon surface, while the desorbed amount reflected the effect of pore structure. Temperature-programmed desorption (TPD) and thermal gravimetric analysis (TGA) showed that the retained sulfurous compounds were strongly bonded to the carbon surface. In addition, surface chemistry of the sorbent might determine the predominant form of adsorbate on the surface. 38 refs., 7 figs., 3 tabs.},
doi = {10.1021/es0507158},
journal = {Environmental Science and Technology},
number = 24,
volume = 39,
place = {United States},
year = {Thu Dec 15 00:00:00 EST 2005},
month = {Thu Dec 15 00:00:00 EST 2005}
}
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Journal Article:
DOI:  10.1021/es0507158
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  • ; ; - Journal of Colloid and Interface Science
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  • ; ; - Environmental Progress; (United States)
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