Premium
Direct oxidation of hydrogen sulphide to sulphur using impregnated activated carbon catalysts
Author(s) -
Dalai Ajay K.,
Cundall Michael T.,
De Mahuya
Publication year - 2008
Publication title -
the canadian journal of chemical engineering
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.404
H-Index - 67
eISSN - 1939-019X
pISSN - 0008-4034
DOI - 10.1002/cjce.20034
Subject(s) - activated carbon , catalysis , chemistry , sulfur , potassium carbonate , inorganic chemistry , nuclear chemistry , carbon fibers , mesoporous material , ammonium iodide , adsorption , organic chemistry , materials science , composite number , composite material
Low concentrations of H 2 S were directly oxidized to sulphur and small quantities of SO 2 , over seven different activated carbons with or without impregnation. The effectiveness of virgin activated carbon was tested at 175°C, 700 kPa, and O 2 /H 2 S ratio with 5% greater than stoichiometry. The conversion of H 2 S was 99.9 mol% with SO 2 production of 3–6%, for 360 min runtime for Fisher coconut shell activated carbon and 648 min for Envirotrol bituminous (EB) activated carbon. Then the activated carbons became deactivated due to deposition of sulphur on the surface. Under these conditions mesoporous activated carbons such as EB and Hydrodarco had the longest breakthrough time. The addition of 5.5 wt% ammonium iodide, potassium iodide and potassium carbonate individually to EB decreased the production of SO 2 while having minimal effect on the overall H 2 S conversion. The addition of 5.5 wt% NH 4 I decreased the average SO 2 production from 2.5% to 0.9%. The activation energy for the H 2 S oxidation on the 5.5 wt% NH 4 I on EB activated carbon was determined to be 40 kJ/mol.