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Title: Activated carbon catalyst for selective oxidation of hydrogen sulphide: on the influence of pore structure, surface characteristics, and catalytically-active nitrogen

Abstract

The catalytic oxidation of hydrogen sulphide (H2S) on various activated carbon materials was studied. The effects of pore structure, surface characteristics, and nitrogen content on the activity and selectivity of the carbons towards oxidation of H2S were investigated. It was found that a high volume of both micropores and small mesopores, in combination with a relatively narrow pore size distribution, were crucial for the retention of sulphur dioxide (SO2), a by-product of H2S oxidation. For the retention of carbonyl sulphide (COS), another H2S oxidation by-product, high surface reactivity with a significant amount of basic groups were found to be important. The only carbon with all these characteristics, and consequently the carbon that was able to retain both H2S and COS for an extended period of time, was an experimental product, 'WSC'. This carbon was found to be superior to the other carbons studied, exhibiting high activity and selectivity for oxidation of H2S to sulphur. H2S breakthrough capacities and selectivity values of the carbons were found to be dependent on the nitrogen content of the carbons. In a hydrogen stream, carbons possessing the highest nitrogen contents exhibited the greatest H2S breakthrough capacities but, at the same time, the lowest selectivity withmore » respect to sulphur formation. In reformate streams, the maximum breakthrough capacity and greatest selectivity were exhibited by carbons with a nitrogen content of about 1-1.5 wt%.« less

Authors:
 [1];  [1];  [1];  [1];  [1]
  1. ORNL
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
FE USDOE - Office of Fossil Energy (FE)
OSTI Identifier:
958760
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Carbon; Journal Volume: 45; Journal Issue: 6
Country of Publication:
United States
Language:
English
Subject:
08 HYDROGEN; ACTIVATED CARBON; BY-PRODUCTS; CAPACITY; CARBON; CARBONYLS; CATALYSTS; DISTRIBUTION; HYDROGEN; NITROGEN; OXIDATION; PORE STRUCTURE; RETENTION

Citation Formats

Baskova, Svetlana, Baker, Frederick S, Wu, Xianxian, Armstrong, Timothy R., and Schwartz, Viviane. Activated carbon catalyst for selective oxidation of hydrogen sulphide: on the influence of pore structure, surface characteristics, and catalytically-active nitrogen. United States: N. p., 2007. Web. doi:10.1016/j.carbon.2007.01.005.
Baskova, Svetlana, Baker, Frederick S, Wu, Xianxian, Armstrong, Timothy R., & Schwartz, Viviane. Activated carbon catalyst for selective oxidation of hydrogen sulphide: on the influence of pore structure, surface characteristics, and catalytically-active nitrogen. United States. doi:10.1016/j.carbon.2007.01.005.
Baskova, Svetlana, Baker, Frederick S, Wu, Xianxian, Armstrong, Timothy R., and Schwartz, Viviane. Mon . "Activated carbon catalyst for selective oxidation of hydrogen sulphide: on the influence of pore structure, surface characteristics, and catalytically-active nitrogen". United States. doi:10.1016/j.carbon.2007.01.005.
@article{osti_958760,
title = {Activated carbon catalyst for selective oxidation of hydrogen sulphide: on the influence of pore structure, surface characteristics, and catalytically-active nitrogen},
author = {Baskova, Svetlana and Baker, Frederick S and Wu, Xianxian and Armstrong, Timothy R. and Schwartz, Viviane},
abstractNote = {The catalytic oxidation of hydrogen sulphide (H2S) on various activated carbon materials was studied. The effects of pore structure, surface characteristics, and nitrogen content on the activity and selectivity of the carbons towards oxidation of H2S were investigated. It was found that a high volume of both micropores and small mesopores, in combination with a relatively narrow pore size distribution, were crucial for the retention of sulphur dioxide (SO2), a by-product of H2S oxidation. For the retention of carbonyl sulphide (COS), another H2S oxidation by-product, high surface reactivity with a significant amount of basic groups were found to be important. The only carbon with all these characteristics, and consequently the carbon that was able to retain both H2S and COS for an extended period of time, was an experimental product, 'WSC'. This carbon was found to be superior to the other carbons studied, exhibiting high activity and selectivity for oxidation of H2S to sulphur. H2S breakthrough capacities and selectivity values of the carbons were found to be dependent on the nitrogen content of the carbons. In a hydrogen stream, carbons possessing the highest nitrogen contents exhibited the greatest H2S breakthrough capacities but, at the same time, the lowest selectivity with respect to sulphur formation. In reformate streams, the maximum breakthrough capacity and greatest selectivity were exhibited by carbons with a nitrogen content of about 1-1.5 wt%.},
doi = {10.1016/j.carbon.2007.01.005},
journal = {Carbon},
number = 6,
volume = 45,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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