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Efficient Recycling of High-grade Concentrate Powders from Feldspar Slime Using Mechanochemically Assisted Acid Leaching

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Jinshan Lu
Jinshan Lu
Jinshan Lu
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Junxiong Zhan
Junxiong Zhan
Junxiong Zhan
  • This person is not on ResearchGate, or hasn't claimed this research yet.
Di Wang
Di Wang
Di Wang
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Abstract and Figures

Feldspar beneficiation produces large amounts of slime waste, which should be efficiently recycled to achieve the economic and environmental benefits. In this study, mechanochemically assisted acid leaching (MAL) was employed to efficiently recycle high-grade concentrate powders, and the physically beneficiated powder from feldspar slime was initially used as a feedstock to reduce gangue mineral disturbance. Milling time and leaching parameters were investigated to reveal their effects on the mass recovery and whiteness of concentrate powders, and the purification mechanism was clarified by chemical reactions and leaching kinetics. The colored minerals were partially liberated and removed by the mechanochemical treatment and further reduced by acid leaching. The optimal MAL process consists of 2 h milling of the feedstock powder in the 5% HCl solution and acid leaching at 95 °C for 4 h. When the feldspar slime was beneficiated by the combination of magnetic separation and MAL, the mass recovery of the ultrafine (0.72 μm) concentrate powder was 76.7%, with a grade of 0.10% Fe2O3. The whiteness’s of the powder and the burnt sample were 91.2% and 64.3% respectively. This facile processing route enables commercial recovery of high-grade concentrate powders from feldspar slime, thus promoting sustainable exploitation of feldspar resources. Graphical Abstract
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Vol.:(0123456789)
Waste and Biomass Valorization (2024) 15:3811–3821
https://doi.org/10.1007/s12649-024-02426-2
ORIGINAL PAPER
Efficient Recycling ofHigh‑grade Concentrate Powders fromFeldspar
Slime Using Mechanochemically Assisted Acid Leaching
JinshanLu1 · JunxiongZhan1· DiWang1
Received: 8 August 2023 / Accepted: 10 January 2024 / Published online: 16 February 2024
© The Author(s), under exclusive licence to Springer Nature B.V. 2024
Abstract
Feldspar beneficiation produces large amounts of slime waste, which should be efficiently recycled to achieve the economic
and environmental benefits. In this study, mechanochemically assisted acid leaching (MAL) was employed to efficiently
recycle high-grade concentrate powders, and the physically beneficiated powder from feldspar slime was initially used as
a feedstock to reduce gangue mineral disturbance. Milling time and leaching parameters were investigated to reveal their
effects on the mass recovery and whiteness of concentrate powders, and the purification mechanism was clarified by chemi-
cal reactions and leaching kinetics. The colored minerals were partially liberated and removed by the mechanochemical
treatment and further reduced by acid leaching. The optimal MAL process consists of 2h milling of the feedstock powder
in the 5% HCl solution and acid leaching at 95°C for 4h. When the feldspar slime was beneficiated by the combination of
magnetic separation and MAL, the mass recovery of the ultrafine (0.72μm) concentrate powder was 76.7%, with a grade of
0.10% Fe2O3. The whiteness’s of the powder and the burnt sample were 91.2% and 64.3% respectively. This facile process-
ing route enables commercial recovery of high-grade concentrate powders from feldspar slime, thus promoting sustainable
exploitation of feldspar resources.
Graphical Abstract
Lattice impurity
Inclusion
Associated mineral
MCT AL
Gel layers
Feldspars
Keywords Feldspar slime· Colored minerals· Mechanochemical treatment· Acid leaching· Burnt whiteness
Statement ofNovelty
Mechanochemical assisted acid leaching provides an eco-
nomically viable method to recover high quality concentrate
powders from feldspar slime with significantly higher mass
recoveries compared to physical beneficiation.
* Jinshan Lu
1474202488@qq.com
1 School ofMaterials Science andEngineering, Nanchang
Hangkong University, Nanchang330063, Jiangxi, China
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
... Furthermore, the release rate was higher in oxalic acid compared to acetic acid. Lu et al. [43] utilised mechanochemically assisted acid leaching (MAL) to recycle high-grade concentrate powders effectively. Under optimal MAL conditions, they achieved a mass recovery of 76.7% for ultrafine (0.72 μm) concentrate powder with a grade of 0.10% Fe 2 O 3 . ...
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