Sulfur removal from bauxite water slurry (BWS) electrolysis intensified by ultrasonic

Lan Ge; Xuzhong Gong; Zhi Wang; Lixin Zhao; Yuhua Wang; Mingyong Wang

doi:10.1016/j.ultsonch.2015.03.010

Sulfur removal from bauxite water slurry (BWS) electrolysis intensified by ultrasonic

Ultrason Sonochem. 2015 Sep:26:142-148. doi: 10.1016/j.ultsonch.2015.03.010. Epub 2015 Mar 19.

Authors

Lan Ge¹, Xuzhong Gong², Zhi Wang³, Lixin Zhao⁴, Yuhua Wang³, Mingyong Wang⁵

Affiliations

¹ National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology, Key Laboratory of Green Process and Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, PR China. Electronic address: lange0311@163.com.
² National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology, Key Laboratory of Green Process and Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, PR China. Electronic address: xzgong@ipe.ac.cn.
³ National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology, Key Laboratory of Green Process and Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, PR China.
⁴ Department of Environment Science and Safety Engineering, Tianjin University of Technology, Tianjin 300384, PR China.
⁵ National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology, Key Laboratory of Green Process and Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, PR China. Electronic address: mywang@ipe.ac.cn.

PMID: 25818363
DOI: 10.1016/j.ultsonch.2015.03.010

Abstract

Effects of ultrasonic on desulfurization ratio from bauxite water slurry (BWS) electrolysis in NaOH solution were examined under constant current. The results indicated that ultrasonic improved the desulfurization ratio at high temperatures because of the diffusion and transfer of oxygen gas in electrolyte. However, due to the increase in oxygen gas emission, ultrasonic could not improve the desulfurization ratio obviously at low temperatures. Additionally, the particle size of bauxite became fine in the presence of ultrasonic, indicating that the mass transfer of FeS2 phase was improved. According to the polarization curves, the current density increased in the presence of ultrasonic, indicating that the mass transfer of liquid phase was improved. The apparent activation energy (AAE) of electrode reaction revealed that ultrasonic did not change the pathway of water electrolysis. However, ultrasonic changed the pathway of BWS electrolysis, converting indirect oxidation into direct oxidation. The AAE of BWS electrolysis in the presence of ultrasonic was higher than that in the absence of ultrasonic. And the low AAEs (less than 20 kJ/mol) clearly indicated the diffusion control during BWS electrolysis reaction.

Keywords: Desulfurization; Electrolysis; High sulfur bauxite; Kinetics; Polarization curve; Ultrasonic.

Publication types

Research Support, Non-U.S. Gov't