To main content

A XANES study of sulfur speciation and reactivity in cokes for anodes used in aluminum production

Abstract

Availability of anode raw materials in the growing aluminum industry results in a wider range of petroleum cokes being used to produce carbon anodes. The boundary between anode grade cokes and what previously was considered non-anode grades are no longer as distinct as before, leading to introduction of cokes with higher sulfur and higher trace metal impurity content in anode manufacturing. In this work, the chemical nature of sulfur in five industrial cokes, ranging from 1.42 to 5.54 wt pct S, was investigated with K-edge XANES, while the reactivity of the cokes towards CO2 was measured by a standard mass loss test. XANES identified most of the sulfur as organic sulfur compounds. In addition, a significant amount is identified (16 to 53 pct) as S-S bound sulfur. A strong inverse correlation is observed between CO2-reactivity and S-S bound sulfur in the cokes, indicating that the reduction in reactivity is more dependent on the amount of this type of sulfur compound rather than the total amount of sulfur or the amount of organic sulfur.
Read the publication

Category

Academic article

Language

English

Author(s)

Affiliation

  • SINTEF Industry / Metal Production and Processing
  • Norwegian University of Science and Technology
  • Massey University - Branch: Palmerston North Campus

Year

2018

Published in

Metallurgical and Materials Transactions B

ISSN

1073-5615

Volume

49

Issue

3

Page(s)

1434 - 1443

View this publication at Norwegian Research Information Repository