Recovery of Lead from Zinc Plant
Residue by Alkaline Leaching Process
Followed by Cementation
Jonghyun Kim, Min-seuk Kim, Kyeong Woo Chung, Kurniawan
and Jae-chun Lee
Abstract Present work focuses on recovery of lead from a zinc plant residue (ZPR)
in alkaline media. Firstly, Zn and Pb were selectively extracted in NaOH from ZPR
containing 56.9% Pb, 0.34% Ag, 3.93% Zn, and 0.88% Cu. Lead was effectively
leached in a two-step process. The leach-I solubilized 39.5% Pb and 58.5% Zn in
2.0 M NaOH at 25 °C and 10% pulp density in 30 min. Subsequent leaching in 3.0 M
NaOH yielded overall extraction of >99% Pb and 67% Zn with stage efficiency of
59.5% Pb and 8.5% Zn. Above 99.9% Pb was recovered from the leach liquor in
30 min at 25 °C and Zn: Pb mole ratio = 1.2:1.0 by cementation using Zn powder.
Interestingly silver in the final residue was enriched from 0.3% to 1.17% making it
a promising resource of Ag.
Keywords Zinc plant residue · Lead · Zinc · Alkaline leaching · Cementation ·
Recovery
Introduction
The primary zinc is produced from its sulfide ores such as sphalerite, which accounts
for more than 80% of the metal obtained globally using the conventional hydrometallurgical process combining the roasting, leaching, purification, and electrowinning
steps [1, 2]. In the hydrometallurgical processing of zinc, the sulfide ore is first
converted to the ZnO-rich calcine which is then subjected to the leaching with the
sulfuric acid followed by a hot sulfuric acid leach step [3]. After the leaching process is over, the leach liquor after liquid/solid separation is purified and electrowon
J. Kim · M. Kim · Kurniawan · J. Lee (B)
Resources Recycling, Korea University of Science and Technology (UST), Daejeon 34113,
Republic of Korea
e-mail: jclee@kigam.re.kr
J. Kim · M. Kim · K. W. Chung · Kurniawan · J. Lee
Mineral Resources Research Division Korea, Institute of Geoscience and Mineral Resources
(KIGAM), Daejeon 34132, Republic of Korea
© 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_21
253
Residue by Alkaline Leaching Process
Followed by Cementation
Jonghyun Kim, Min-seuk Kim, Kyeong Woo Chung, Kurniawan
and Jae-chun Lee
Abstract Present work focuses on recovery of lead from a zinc plant residue (ZPR)
in alkaline media. Firstly, Zn and Pb were selectively extracted in NaOH from ZPR
containing 56.9% Pb, 0.34% Ag, 3.93% Zn, and 0.88% Cu. Lead was effectively
leached in a two-step process. The leach-I solubilized 39.5% Pb and 58.5% Zn in
2.0 M NaOH at 25 °C and 10% pulp density in 30 min. Subsequent leaching in 3.0 M
NaOH yielded overall extraction of >99% Pb and 67% Zn with stage efficiency of
59.5% Pb and 8.5% Zn. Above 99.9% Pb was recovered from the leach liquor in
30 min at 25 °C and Zn: Pb mole ratio = 1.2:1.0 by cementation using Zn powder.
Interestingly silver in the final residue was enriched from 0.3% to 1.17% making it
a promising resource of Ag.
Keywords Zinc plant residue · Lead · Zinc · Alkaline leaching · Cementation ·
Recovery
Introduction
The primary zinc is produced from its sulfide ores such as sphalerite, which accounts
for more than 80% of the metal obtained globally using the conventional hydrometallurgical process combining the roasting, leaching, purification, and electrowinning
steps [1, 2]. In the hydrometallurgical processing of zinc, the sulfide ore is first
converted to the ZnO-rich calcine which is then subjected to the leaching with the
sulfuric acid followed by a hot sulfuric acid leach step [3]. After the leaching process is over, the leach liquor after liquid/solid separation is purified and electrowon
J. Kim · M. Kim · Kurniawan · J. Lee (B)
Resources Recycling, Korea University of Science and Technology (UST), Daejeon 34113,
Republic of Korea
e-mail: jclee@kigam.re.kr
J. Kim · M. Kim · K. W. Chung · Kurniawan · J. Lee
Mineral Resources Research Division Korea, Institute of Geoscience and Mineral Resources
(KIGAM), Daejeon 34132, Republic of Korea
© 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_21
253