I/We Claim:
1. A process for recovering cathode active material from a cathode scrap, said
process comprising the steps of:
a. heating a first part of the cathode scrap along with an acid in the
5 presence of one part of a reducing agent to obtain a first solution,
filtering the first solution to obtain a first residual solid and a first
leachate;
b. treating the first residual solid and a second part of the cathode scrap
with the first leachate in the presence of another part of the reducing
10 agent, to obtain a second solution, filtering the second solution to obtain
a final residual solid and a final leachate; and,
c. co-precipitating the final leachate in the presence of a complexing agent
and a precipitating agent to obtain a precursor cathode active material
(p-CAM) and sintering the p-CAM to obtain the cathode active material
15 (CAM).
2. The process as claimed in claim 1, wherein the steps (a) and (b) are carried
out in a closed environment, devoid of oxygen.
3. The process as claimed in claim 1, wherein cathode scrap comprises a
fluoropolymer binder selected from polytetrafluoroethylene (PTFE),
20 fluoroethylene vinyl ether (FEVE), poly(vinylidene fluoride) (PVDF) or
combinations thereof.
4. The process as claimed in any one of the claims 1 to 3, wherein step (b) is
repeated one to four times to separate the fluoropolymer binder from the
cathode scrap.
25 5. The process as claimed in claim 1, wherein the acid is selected from a mineral
acid, an organic acid, or combinations thereof.
6. The process as claimed in claim 1, wherein the acid is in a concentration range
of 1.6 to 3 M.
27
7. The process as claimed in claim 1, wherein the reducing agent is selected
from hydrogen peroxide, carbon based reducing agents, or combinations
thereof.
8. The process as claimed in claim 1, wherein the complexing agent is
5 ammonium hydroxide; and the precipitating agent is sodium hydroxide.
9. The process as claimed in claim 1, wherein the complexing agent is in a
concentration range of 1.5 to 3 M; and the precipitating agent is in a
concentration range of 3 to 6 M.
10. The process as claimed in claim 1, wherein step (a) or step (b) is carried out
10 at a temperature in a range of 50 to 80°C.
11. The process as claimed in claim 1, wherein step (a) or step (b) is carried out
under stirring at a speed in a range of 1500 to 2500 rpm for a time period in a
range of 1 to 3 hours.
12. The process as claimed in claim 1, wherein in step (a), weight of the cathode
15 scrap to total volume of the acid is in a (w/v) ratio range of 1:8 to 1:15.
13. The process as claimed in claim 1, wherein the reducing agent is in a volume
range of 5 to 10% with respect to the total volume of the first solution.
14. The process as claimed in claim 1, wherein the process results in a leaching
efficiency of cathode active material in a range of 65 to 100%.