The end-of-life management of a large number of discarded lithium-ion batteries (LiBs) has become a global issue because of the steady increase in their usage every year. In this study, a novel membrane-integrated hybrid system was developed for recycling commercially valuable metals while treating acidic leach liquor obtained from spent LiBs (mostly LiFePO4 type). Alkaline (NaOH and NH4OH)-pretreated leach liquor (pH adjusted to 5.53) was ultrafiltered to ensure the effective removal of Fe and Al and reduce the turbidity (∼1.6 NTU) prior to processing in a nanofiltration system. The nanofiltration membrane (VNF2) was applied successfully to obtain the rejection values of 92.5% (Ni2+), 94.6% (Co2+), and 95.8% (Mn2+) while permeating > 89.6% of Li+ with 7.5 L/m2·h of flux under optimized conditions of transmembrane pressure (10 bar) and crossflow rate (2.25 m3/h) in the recirculation mode. The fractionation of monovalent ions from bivalent ions was performed in a concentrated mode to enrich the bivalent metal ions, Ni2+, Co2+, and Mn2+ from 0.74, 0.52, and 0.63 g/L to 6.14, 4.59, 5.62 g/L, respectively, at 90% recovery of the feed solution. The Li+ (21.1 g/L) that was contained in the nanofiltrate permeate stream was crystallized into Li2CO3; a purity of 99.5 wt% was obtained at 88.2% recovery using 4 M K2CO3 at an operating temperature of 70 °C. Hence, the proposed novel system can lead to the development of a clean and sustainable process for the recycling of precious metal ions from end-of-life LiBs for reuse on a commercial scale.
|Journal||Chemical Engineering Journal|
|Publication status||Published - 2022 Nov 1|
Bibliographical noteFunding Information:
The authors acknowledge the National Research Foundation (NRF) of the Republic of Korea under the Creative and Challenging Research Program (2021R1I1A1A01060846). Moonis Ali Khan acknowledges the financial support through the Researchers Supporting Project number (RSP2021/345), King Saud University, Riyadh, Saudi Arabia.
© 2022 Elsevier B.V.
All Science Journal Classification (ASJC) codes
- Environmental Chemistry
- Chemical Engineering(all)
- Industrial and Manufacturing Engineering