Effect of Oxidation of Zinc Powder
on Purification of High-Cobalt
and High-Germanium Zinc Sulfate
Solutions
Leixia Zheng, Zhiwei Peng, Liancheng Wang, Lei Yang, Jie Wang,
Wenxing Shang, Mingjun Rao, Guanghui Li and Tao Jiang
Abstract It is popular to use zinc powder to purify electrolytic zinc sulfate solution
via replacement reactions between zinc and other metals in the solution. In view
of easy oxidation of zinc that affects its purification performance, in this study, the
influence of oxidation of zinc powder on the purification of high-cobalt and highgermanium zinc sulfate solutions was explored. The oxidation of zinc powder was
simulated by adding ZnO. It was demonstrated that the oxidation percentages of
fine and coarse zinc powders should not exceed 2.5% and 1.0%, respectively, for
sufficient removal of cobalt from the solution, while for removal of germanium,
the corresponding values were 0.5% and 0.2%. The results can be used for guiding
purification of zinc sulfate solution to meet the requirements of subsequent operation.
Keywords Zinc sulfate solution · Purification · Zinc powder · Cobalt · Germanium
Introduction
The industrial application of metals has been increasing in the past decades, with
about 60 metallic elements in use today [1]. Zinc is the fourth most widely used metal
after iron, aluminum, and copper [2]. The production of refined zinc in 2017 was
approximately 13 million tons [3], and the demand for zinc is expected to remain
strong in the coming years due to the development of zinc-consuming industries [4].
Currently, more than 85% of zinc is produced by hydrometallurgical processes [5].
One of them is the roasting-leaching-electrowinning process [6].
The presence of metallic impurities in the zinc electrolyte is a major problem for
the zinc electrodeposition process [7]. The existence of impurities greatly impacts
the cathodic deposition of zinc, leading to a decrease in zinc current efficiency and to
L. Zheng · Z. Peng (B) · L. Wang · L. Yang · J. Wang · W. Shang · M. Rao · G. Li · T. Jiang
School of Minerals Processing and Bioengineering, Central South University, Changsha 410083,
Hunan, China
e-mail: zwpeng@csu.edu.cn
National Engineering Laboratory for High Efficiency Recovery of Refractory Nonferrous Metals,
Changsha 410083, Hunan, China
© The Minerals, Metals & Materials Society 2020
A. Siegmund et al. (eds.), PbZn 2020: 9th International Symposium
on Lead and Zinc Processing, The Minerals, Metals & Materials Series,
https://doi.org/10.1007/978-3-030-37070-1_58
673
on Purification of High-Cobalt
and High-Germanium Zinc Sulfate
Solutions
Leixia Zheng, Zhiwei Peng, Liancheng Wang, Lei Yang, Jie Wang,
Wenxing Shang, Mingjun Rao, Guanghui Li and Tao Jiang
Abstract It is popular to use zinc powder to purify electrolytic zinc sulfate solution
via replacement reactions between zinc and other metals in the solution. In view
of easy oxidation of zinc that affects its purification performance, in this study, the
influence of oxidation of zinc powder on the purification of high-cobalt and highgermanium zinc sulfate solutions was explored. The oxidation of zinc powder was
simulated by adding ZnO. It was demonstrated that the oxidation percentages of
fine and coarse zinc powders should not exceed 2.5% and 1.0%, respectively, for
sufficient removal of cobalt from the solution, while for removal of germanium,
the corresponding values were 0.5% and 0.2%. The results can be used for guiding
purification of zinc sulfate solution to meet the requirements of subsequent operation.
Keywords Zinc sulfate solution · Purification · Zinc powder · Cobalt · Germanium
Introduction
The industrial application of metals has been increasing in the past decades, with
about 60 metallic elements in use today [1]. Zinc is the fourth most widely used metal
after iron, aluminum, and copper [2]. The production of refined zinc in 2017 was
approximately 13 million tons [3], and the demand for zinc is expected to remain
strong in the coming years due to the development of zinc-consuming industries [4].
Currently, more than 85% of zinc is produced by hydrometallurgical processes [5].
One of them is the roasting-leaching-electrowinning process [6].
The presence of metallic impurities in the zinc electrolyte is a major problem for
the zinc electrodeposition process [7]. The existence of impurities greatly impacts
the cathodic deposition of zinc, leading to a decrease in zinc current efficiency and to
L. Zheng · Z. Peng (B) · L. Wang · L. Yang · J. Wang · W. Shang · M. Rao · G. Li · T. Jiang
School of Minerals Processing and Bioengineering, Central South University, Changsha 410083,
Hunan, China
e-mail: zwpeng@csu.edu.cn
National Engineering Laboratory for High Efficiency Recovery of Refractory Nonferrous Metals,
Changsha 410083, Hunan, China
© The Minerals, Metals & Materials Society 2020
A. Siegmund et al. (eds.), PbZn 2020: 9th International Symposium
on Lead and Zinc Processing, The Minerals, Metals & Materials Series,
https://doi.org/10.1007/978-3-030-37070-1_58
673