# US 10,309,021 B2 · Method for preparing an electrolyte and an electrolyte replenishment system during aluminum electrolysis process

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 10,309,021 B2
- Document ID: US10309021B2
- Status: Granted
- Kind: B2
- Application number: 14/413,473
- Filed: 2012-11-21
- Published: 2015-07-23
- Granted: 2019-06-04
- Earliest claimed: 2012-07-25
- Assignees: Shenzhen Sunxing Light Alloys Materials Co., Ltd.
- Applicants: Shenzhen Sunxing Light Alloys Materials Co., Ltd
- Inventors: Xuemin Chen; Jun Yang; Zhihong Li; Weiping Wu; Shiming Wei
- Web page: https://patentgrep.com/patent/US10309021B2

## CPC

- C25C 3/18: Electrolytes
- C01F 7/54: Double compounds containing both aluminium and alkali metals or alkaline-earth metals
- C25C: PROCESSES FOR THE ELECTROLYTIC PRODUCTION, RECOVERY OR REFINING OF METALS; APPARATUS THEREFOR
- C01F: COMPOUNDS OF THE METALS BERYLLIUM, MAGNESIUM, ALUMINIUM, CALCIUM, STRONTIUM, BARIUM, RADIUM, THORIUM, OR OF THE RARE-EARTH METALS (metal hydrides {monoborane, diborane or addition complexes thereof} C01B6/00; salts of oxyacids of halogens C01B11/00; peroxides, salts of peroxyacids C01B15/00; sulfides or polysulfides of magnesium, calcium, strontium, or barium C01B17/42; thiosulfates, dithionites, polythionates C01B17/64; compounds containing selenium or tellurium C01B19/00; binary compounds of nitrogen with metals C01B21/06; azides C01B21/08; {compounds other than ammonia or cyanogen containing nitrogen and non-metals and optionally metals C01B21/082; amides or imides of silicon C01B21/087}; metal {imides or} amides C01B21/092, {C01B21/0923}; nitrites C01B21/50; {compounds of noble gases C01B23/0005}; phosphides C01B25/08; salts of oxyacids of phosphorus C01B25/16; carbides C01B32/90; compounds containing silicon C01B33/00; compounds containing boron C01B35/00; compounds having molecular sieve properties but not having base-exchange properties C01B37/00; compounds having molecular sieve and base-exchange properties, e.g. crystalline zeolites, C01B39/00; cyanides C01C3/08; salts of cyanic acid C01C3/14; salts of cyanamide C01C3/16; thiocyanates C01C3/20; {double sulfates of magnesium with sodium or potassium C01D5/12; with other alkali metals C01D15/00, C01D17/00})

## Abstract

The disclosure provides a method for preparing an electrolyte and an electrolyte replenishment system during an electrolytic process. The method includes the following steps: Step A: placing aluminum in a reactor, vacuumizing the reactor and feeding an inert gas, heating the reactor to 700-850 degrees centigrade, and adding one or more of potassium fluozirconate, potassium fluoborate, sodium hexafluorozirconate and sodium fluoroborate; and Step B: stirring the reactants for 4-6 hours and extracting the upper molten liquid to obtain an electrolyte replenishment system during an aluminum electrolysis process. The disclosure has the following beneficial effects: when used in the aluminum electrolysis industry, the electrolyte system provided herein can be directly used as an aluminum electrolyte or a replenishment system in an electrolyte without changing existing electrolysis technology to significantly reduce an electrolysis temperature during an aluminum electrolysis process.

## Claims

### Claim 1

A method for preparing an electrolyte comprising the following steps of:
Step A: placing aluminum in a reactor, vacuumizing the reactor and feeding an inert gas, heating the reactor to 700-850 degrees centigrade, and adding only potassium fluozirconate; and
Step B: stirring for 4-6 hours and extracting an upper molten liquid to obtain only zirconium sponge and an
3
2
⁢
KF
·
AlF
3
electrolyte according to a reaction formula of
Al
+
3
4
⁢
K
2
⁢
ZrF
6
=
3
4
⁢
Zr
+
3
2
⁢
KF
·
AlF
3
so as to replenish the
3
2
⁢
KF
·
AlF
3
electrolyte during an electrolytic process.

### Claim 2

A method for preparing an electrolyte during an electrolytic process, including the steps of:
Step A: placing aluminum in a first reactor, vacuumizing the first reactor and feeding inert gas, heating the first reactor to 700-850 degrees centigrade, adding only a first reactant of potassium fluozirconate, stirring 4-6 hours and extracting a first upper molten liquid to obtain only zirconium sponge and a potassium AlF3 cryolite; and placing aluminum in a second reactor, vacuumizing the second reactor and feeding inert gas, heating the second reactor to 700-850 degrees centigrade, adding only a second reactant of sodium hexafluorozirconate, stirring for 4-6 hours and extracting a second upper molten liquid to obtain only zirconium sponge and a sodium AlF3 cryolite; and
Step B: mixing the obtained potassium cryolite with the obtained sodium cryolite in a molar ratio of 1:1 to 1:3.

### Claim 3 (depends on 2)

The method for preparing an electrolyte during an electrolytic process according to claim 2, comprising the steps of:
in said Step A: extracting the first upper molten liquid to obtain the potassium cryolite the molecular formula of which is
3
2
⁢
KF
·
AlF
3
;
and extracting the second upper molten liquid to obtain the sodium cryolite the molecular formula of which is
3
2
⁢
NaF
·
AlF
3
;
and
in said Step B: mixing the obtained potassium cryolite
3
2
⁢
KF
·
AlF
3
with the obtained sodium cryolite
3
2
⁢
NaF
·
AlF
3
in a molar ratio of 1:1 to 1:3.

### Claim 4

A method for preparing an electrolyte comprising the steps of:
Step A: placing aluminum in a reactor, vacuumizing the reactor and feeding an inert gas, heating the reactor to 700-850 degrees centigrade, and adding only sodium hexafluorozirconate; and
Step B: stirring for 4-6 hours and extracting an upper molten liquid to obtain only zirconium sponge and an
3
2
⁢
NaF
·
AlF
3
electrolyte during an aluminum electrolysis process according to a reaction formula of
Al
+
3
4
⁢
Na
2
⁢
ZrF
6
=
3
4
⁢
Zr
+
3
2
⁢
Na
⁢
F
·
AlF
3
.