Sulphation and Sulphate Decomposition in Roasted Nickel Concentrates

The sulphation and sulphate decomposition occurring during the oxidation of nickel concentrates were studied by thermal analysis. Samples of industrial nickel concentrates were heated in inert gas to temperatures between 400°C and 850°C and oxidized isothermally in air or in a 4%O2-96%N2 mixture....

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Main Author: Pandher, Rajan
Other Authors: Utigard, Torstein A.
Language:en_ca
Published: 2010
Subjects:
Online Access:http://hdl.handle.net/1807/24615
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spelling ndltd-TORONTO-oai-tspace.library.utoronto.ca-1807-246152013-11-09T04:12:40ZSulphation and Sulphate Decomposition in Roasted Nickel ConcentratesPandher, Rajansulphationsulphatenickel concentrateroastingsulphate decompositionnonferrous pyrometallurgy0743The sulphation and sulphate decomposition occurring during the oxidation of nickel concentrates were studied by thermal analysis. Samples of industrial nickel concentrates were heated in inert gas to temperatures between 400°C and 850°C and oxidized isothermally in air or in a 4%O2-96%N2 mixture. During isothermal oxidation of the concentrates, SO2 evolved from the roasting reactions led to partial formation of metal sulphates. Following the oxidation and sulphation of the sample, the decomposition of the formed sulphates was studied. This was completed either by heating the sulphated sample to 950°C to thermally decompose the sulphates, or by lowering the partial pressure of oxygen while holding the sample at the isothermal oxidation temperature. The sulphation of the sample was found to follow the parabolic rate law, implying diffusion as the rate controlling-step. The thermal decomposition of the sulphates occurred at a near constant rate, implying zero-order kinetics.Utigard, Torstein A.2010-062010-07-27T19:55:23ZNO_RESTRICTION2010-07-27T19:55:23Z2010-07-27T19:55:23ZThesishttp://hdl.handle.net/1807/24615en_ca
collection NDLTD
language en_ca
sources NDLTD
topic sulphation
sulphate
nickel concentrate
roasting
sulphate decomposition
nonferrous pyrometallurgy
0743
spellingShingle sulphation
sulphate
nickel concentrate
roasting
sulphate decomposition
nonferrous pyrometallurgy
0743
Pandher, Rajan
Sulphation and Sulphate Decomposition in Roasted Nickel Concentrates
description The sulphation and sulphate decomposition occurring during the oxidation of nickel concentrates were studied by thermal analysis. Samples of industrial nickel concentrates were heated in inert gas to temperatures between 400°C and 850°C and oxidized isothermally in air or in a 4%O2-96%N2 mixture. During isothermal oxidation of the concentrates, SO2 evolved from the roasting reactions led to partial formation of metal sulphates. Following the oxidation and sulphation of the sample, the decomposition of the formed sulphates was studied. This was completed either by heating the sulphated sample to 950°C to thermally decompose the sulphates, or by lowering the partial pressure of oxygen while holding the sample at the isothermal oxidation temperature. The sulphation of the sample was found to follow the parabolic rate law, implying diffusion as the rate controlling-step. The thermal decomposition of the sulphates occurred at a near constant rate, implying zero-order kinetics.
author2 Utigard, Torstein A.
author_facet Utigard, Torstein A.
Pandher, Rajan
author Pandher, Rajan
author_sort Pandher, Rajan
title Sulphation and Sulphate Decomposition in Roasted Nickel Concentrates
title_short Sulphation and Sulphate Decomposition in Roasted Nickel Concentrates
title_full Sulphation and Sulphate Decomposition in Roasted Nickel Concentrates
title_fullStr Sulphation and Sulphate Decomposition in Roasted Nickel Concentrates
title_full_unstemmed Sulphation and Sulphate Decomposition in Roasted Nickel Concentrates
title_sort sulphation and sulphate decomposition in roasted nickel concentrates
publishDate 2010
url http://hdl.handle.net/1807/24615
work_keys_str_mv AT pandherrajan sulphationandsulphatedecompositioninroastednickelconcentrates
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