1. A metal recovery method for recovering metals from a positive electrode material for lithium ion batteries containing lithium and a transition metal element, the method comprising:
an acid leaching step of dissolving the positive electrode material in an acid solution to generate lithium ions and transition metal ions in the acid solution;
a dialysis step of flowing the acid solution containing the lithium ions and the transition metal ions and a recovery liquid, with an anion permeable membrane interposed between the acid solution and the recovery liquid, thereby permeating the lithium ions from the acid solution to the recovery liquid; and
a lithium recovery step of recovering the lithium ions from the recovery liquid containing the permeated lithium ions;
wherein the dialysis step is performed by a process selected from the group consisting of pressure dialysis and centrifugal dialysis.
2. The metal recovery method according to claim 1, wherein the acid solution is a mineral acid containing halide ions.
3. The metal recovery method according to claim 2, wherein the mineral acid containing halide ions is hydrochloric acid.
4. The metal recovery method according to claim 1, wherein the acid solution is sulfuric acid or nitric acid.
5. The metal recovery method according to claim 1, wherein the transition metal element is cobalt.
6. The metal recovery method according to claim 1, wherein, in the dialysis step, the acid solution and the recovery liquid are flowed countercurrently to each other in a bath, with the anion permeable membrane interposed therebetween.
7. The metal recovery method according to claim 1, wherein the transition metal ions are recovered from the acid solution that has undergone the dialysis step.
8. The metal recovery method according to claim 1, wherein, in the dialysis step, the recovery liquid containing the permeated lithium ions and another recovery liquid are flowed, with an anion permeable membrane interposed therebetween, thereby permeating the lithium ions from the recovery solution to the another recovery liquid to perform dialysis a plurality of times.
9. The metal recovery method according to claim 1, wherein, in the dialysis step, acids in the acid solution are also permeated to the recovery liquid;
in the lithium recovery step, the acids in the recovery liquid are recovered; and
the recovered acids are used in the acid leaching step.
10. The metal recovery method according to claim 1, wherein the dialysis step is performed by centrifugation, and the acid solution is flowed into an inner bath having the anion permeable membrane on an outer periphery of rotator; the recovery liquid is flowed between the inner bath and an outer bath located outside the inner bath; and the dialysis is performed while rotating the inner bath.
11. The metal recovery method according to claim 10, wherein, in the dialysis step, the outer bath is rotated in a direction opposite to a rotating direction of the inner bath.
12. The metal recovery method according to claim 10, wherein the acid solution and the recovery liquid flow in opposite directions with respect to a rotating shaft direction of the inner bath or the outer bath.
13. The metal recovery method according to claim 10, wherein an acid solution inflow port from which the acid solution is flowed into the inner bath or a recovery liquid inflow port from which the recovery liquid is flowed into the outer bath is arranged inclined with respect to a rotation axis of the inner bath or a rotation axis of the outer bath so that the acid solution or the recovery liquid flows toward an outer circumference of the inner bath or the outer bath.
14. The metal recovery method according to claim 1, wherein a stirring means for stirring the acid solution or the recovery liquid is provided.
15. A metal recovery method comprising:
a dialysis treatment step of subjecting a positive electrode material containing a composite oxide of lithium and a transition metal element to dialysis treatment in a bath in which an anion selectively permeable membrane for selectively permeating the lithium in the positive electrode material and an acid solution containing halide ions are provided; wherein the dialysis is performed by a process selected from the group consisting of pressure dialysis and centrifugal dialysis.
16. The metal recovery method according to claim 15, wherein the transition metal element is Co.
17. The metal recovery method according to claim 15, wherein the halide ion is Cl\u2014.
18. The metal recovery method according to claim 15, wherein, in the dialysis treatment step, the positive electrode material is separated into a concentrated liquid of lithium and acids obtained by treating the positive electrode material with the acid solution containing halide ions, and a concentrated liquid of transition metal ions of the transition metal element.
19. The metal recovery method according to claim 18, further comprising:
a step of recovering the acids from the concentrated liquid of lithium and acids separated in the dialysis treatment step; and
a step of recovering the lithium from a residual liquid of the concentrated liquid of lithium and acids, from which the acids have been recovered through the acid recovery step.
20. The metal recovery method according to claim 19, wherein, in the lithium recovery step, a carbonate is mixed with the residual liquid to generate lithium carbonate, thereby recovering the lithium.
21. The metal recovery method according to claim 15, wherein the acid solution is a strong acid.
22. A dialysis device comprising:
a first bath;
a second bath;
an acid solution inflow port from which an acid solution containing lithium ions and transition metal ions is flowed into the first bath;
a recovery liquid inflow port from which a recovery liquid is flowed into the second bath;
an anion permeable membrane which is provided between the first bath and the second bath, through which the lithium ions are permeated from the acid solution which resides on a membrane surface on the side of the first bath to the recovery liquid which resides on a membrane surface on the side of the second bath;
an acid solution outflow port from which the acid solution is flowed out of the first bath; and
a recovery liquid outflow port from which the recovery liquid, in which the lithium ions have been dissolved by dialysis, is flowed out of the second bath;
wherein the first bath is provided inside the second bath and relatively rotatable with respect to the second bath.
23. A dialysis device comprising:
a first tank;
a second tank;
an acid solution inflow port from which an acid solution containing lithium ions and transition metal ions is flowed into the first tank;
a recovery liquid inflow port from which a recovery liquid is flowed into the second tank;
an anion permeable membrane which is provided between the first tank and the second tank, through which the lithium ions are permeated from the acid solution which resides on a membrane surface on the side of the first tank to the recovery liquid which resides on a membrane surface on the side of the second tank;
an acid solution outflow port from which the acid solution is flowed out of the first tank; and
a recovery liquid outflow port from which the recovery liquid, in which the lithium ions have been dissolved by dialysis, is flowed out of the second tank;
wherein the first tank is a pressure dialysis tank.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A cellulose acylate film, comprising an acyl-modified compound of a reduction product of a ketone compound-formaldehyde polymer.
2. The cellulose acylate film according to claim 1, wherein the reduction product of a ketone compound-formaldehyde polymer is that of an alkyl aryl ketone-formaldehyde polymer.
3. The cellulose acylate film according to claim 1, wherein the acyl-modified compound is a compound represented by the following Formula (I):
(wherein, R1 and R2 each independently represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms; R3, R4 and R5 each independently represent a hydrogen atom, a formyl group or an alkylcarbonyl group having 2 to 15 carbon atoms, but not all of them represent hydrogen atoms; A and B each independently represent an aryl group having 6 to 10 carbon atoms; R6 and R7 each independently represent a hydrogen atom, a halogen atom or an alkyl or alkoxy group having 1 to 6 carbon atoms; m and n each independently represent an integer of 0 or 1 or more, but are not 0 simultaneously; p and q are each independently 0 or an integer of 1 or 2).
4. The cellulose acylate film according to claim 1, wherein the molar absorption coefficient of the acyl-modified compound of the reduction product of a ketone compound-formaldehyde polymer is 2000 or less in a wavelength range of 230 to 700 nm.
5. The cellulose acylate film according to claim 1, wherein a number average molecular weight of the acyl-modified compound of the reduction product of a ketone compound-formaldehyde polymer is 500 or more and 1500 or less.
6. The cellulose acylate film according to claim 1, wherein in-plain retardation (Re) and retardation in a thickness direction (Rth), as determined at a measurement wavelength of 548 nm, satisfy relationships represented by the following formulae (1) and (2) and both Re and Rth show higher reverse dispersibility along with the increase of wavelength measured.
30 nm\u2266Re(548)\u2266150 nm\u2003\u2003formula (1)
70 nm\u2266Rth(548)\u2266300 nm\u2003\u2003formula (2)
(wherein, Re(548) and Rth(548) represent respectively the in-plain retardation and the retardation for the thickness direction at a wavelength of 548 nm).
7. A polarizing plate, comprising a polarizing film and two transparent protective films set on both sides of the polarizing film, wherein at least one of the transparent protective films is the cellulose acylate film according to claim 1.
8. A liquid crystal display device, comprising a liquid crystal cell and two polarizing plates set on both sides of the liquid crystal cell, wherein at least one of the polarizing plates is the polarizing plate according to claim 7.
9. The liquid crystal display device according to claim 8, wherein a display mode of the liquid crystal display device is a VA mode.
10. An acyl-modified compound of a reduction product of a ketone compound-formaldehyde polymer represented by the following Formula (I).
(wherein, R1 and R2 each independently represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms; R3, R4 and R5 each independently represent a hydrogen atom, a formyl group or an alkylcarbonyl group having 2 to 15 carbon atoms, but not all of them represent hydrogen atoms; A and B each independently represent an aryl group having 6 to 10 carbon atoms; R6 and R7 each independently represent a hydrogen atom, a halogen atom or an alkyl or alkoxy group having 1 to 6 carbon atoms; m and n each independently represent an integer of 0 or 1 or more, but are not 0 simultaneously; p and q are each independently 0 or an integer of 1 or 2).