阅读说明：本技术 常温电解铝工艺 (Normal temperature aluminum electrolysis process ) 是由 曹大平 于 2019-11-11 设计创作，主要内容包括：本发明提出的常温电解铝工艺属电化学与有色金属冶金技术领域,其特点在于：以乙醇钠、乙二醇溶液为电解质,加入适量氧化钠、三氧化二铝粉末,在40摄氏度强力搅拌,混合体通过以石墨为阳极,铝板为阴极的电解槽,控制电极间距与混合体流速,于0中40摄氏度电解,得氧气与金属铝,密封石墨阳极区,氧气分离微量介质后导出,定期更换阴极板得电解铝。(The invention provides a normal temperature electrolytic aluminum process, belonging to the technical field of electrochemistry and nonferrous metallurgy, which is characterized in that: the method comprises the steps of taking sodium ethoxide and ethylene glycol solution as electrolytes, adding a proper amount of sodium oxide and aluminum oxide powder, stirring strongly at 40 ℃, electrolyzing the mixture at 40 ℃ in 0 by using graphite as an anode and an aluminum plate as a cathode in an electrolytic cell, sealing a graphite anode area, separating trace media from oxygen, then leading out, and periodically replacing a cathode plate to obtain electrolytic aluminum.)

1. The normal temperature electrolytic aluminum process provided by the invention has the following basic characteristics:

and (3) cathode reaction: 4NaAlO₂+12e=2Na₂O+4Al+6O^-2

And (3) anode reaction: 2O^-2=O₂+4e

And (3) total reaction: 4NaAlO₂=2Na₂O+4Al+3O₂

Pre-dissolving reaction: na (Na)₂O+Al₂O₃=2NaAlO₂。

2. The process takes sodium ethoxide glycol solution as electrolyte, contains 1 percent ~ 10 percent of sodium ethoxide, and also serves as a solvent for electric conduction and conversion of sodium oxide and aluminum oxide.

3. The electrolysis temperature is 0 ~ 40 ℃, the temperature of the electrolysis mixed liquid entering the tank is 0 ~ 10 ℃, the temperature of the electrolysis mixed liquid leaving the tank is 30 ~ 40 ℃, the distance between electrodes, the current density and the circulation speed of the electrolyte are adjusted or a heat dissipation device is additionally arranged, the temperature of the system is kept not higher than 40 ℃, and the solvent is prevented from being oxidized.

4. And removing oxidation products in the system at regular intervals, and removing acidic oxidation products by adopting alkaline ion exchange resin or an aluminum oxide adsorption column to maintain normal operation of the system.

5. Graphite plate is used as anode, and metal aluminium plate is used as cathode.

6. The distance between the cathode and the anode is 10 ~ 50mm, Al₂O₃After the powder is pre-dissolved, the mixed electrolyte flows across the plates to complete electrolysis.

7. Before electrolysis, the pre-dissolving process is to add 1% ~ 10% Na into sodium ethoxide and ethylene glycol solution₂O, adding Al in proportion₂O₃The powder is strongly stirred for 15 ~ 120 minutes at 30 ~ 40 ℃, sodium ethoxide and sodium oxide are circulated during electrolysis, only aluminum oxide needs to be quantitatively added into the electrolyte taken out of the tank, and the powder is strongly stirred for 15 ~ 120 minutes at 30 ~ 40 ℃, and the sodium ethoxide and the sodium oxide are supplemented according to the detected amount.

8. The anode area of the electrolytic cell is sealed in an isolated way, and oxygen is separated by static separation or molecular sieve adsorption to recover the glycol solvent and then is led out for storage.

9. And (3) eluting the solvent adsorbed by the molecular sieve with absolute ethyl alcohol, recovering the absolute ethyl alcohol, adding the recovered absolute ethyl alcohol into the system for use, and recycling the molecular sieve after the absolute ethyl alcohol is removed.

10. And replacing the cathode aluminum plate periodically, and keeping the system in a fully sealed and anhydrous state.

Technical Field

The invention provides a normal temperature electrolytic aluminum process technology, belonging to the technical field of electrochemistry and non-ferrous metal hydrometallurgy.

Background

The traditional high-temperature electrolytic aluminum process has a long history, but has high energy consumption and serious pollution. Because of the abundant aluminum ore resources, aluminum and aluminum alloy are the most important light metals in modern times and are widely applied to national defense, industry and life. The research and development of a brand new normal-temperature low-energy-consumption aluminum electrolysis technology can greatly reduce the energy consumption of aluminum metallurgy and reduce the environmental pollution, and has great significance for realizing sustainable development by protecting the ecological environment.

Disclosure of Invention

The normal temperature electrolytic aluminum process provided by the invention has the following basic characteristics:

and (3) cathode reaction: 4NaAlO₂+12e=2Na₂O+4Al+6O^-2

And (3) anode reaction: 2O^-2=O₂+4e

And (3) total reaction: 4NaAlO₂=2Na₂O+4Al+3O₂

Pre-dissolving reaction: na (Na)₂O+Al₂O₃=2NaAlO₂。

The process takes sodium ethoxide glycol solution as electrolyte, contains 1 percent ~ 10 percent of sodium ethoxide, and also serves as a conductive and sodium oxide and aluminum oxide conversion solvent.

The electrolysis temperature is 0 ~ 40 ℃, the temperature of the electrolysis mixed liquid entering the tank is 0 ~ 10 ℃, the temperature of the electrolysis mixed liquid leaving the tank is 30 ~ 40 ℃, the distance between electrodes, the current density and the circulation speed of the electrolyte are adjusted or a heat dissipation device is additionally arranged, the temperature of the system is kept not higher than 40 ℃, and the solvent is prevented from being oxidized.

And removing oxidation products in the system at regular intervals, and removing acidic oxidation products by adopting alkaline ion exchange resin or an aluminum oxide adsorption column to maintain normal operation of the system.

Graphite plate is used as anode, metal aluminium plate is used as cathode, the distance between cathode and anode is 10 ~ 50mm, Al₂O₃After the powder is pre-dissolved, the mixed electrolyte flows across the plates to complete electrolysis.

Before electrolysis, the pre-dissolving process is to add 1% ~ 10% Na into sodium ethoxide and ethylene glycol solution₂O, adding Al in proportion₂O₃The powder is strongly stirred for 15 ~ 120 minutes at 30 ~ 40 ℃, sodium ethoxide and sodium oxide are circulated during electrolysis, only aluminum oxide needs to be quantitatively added into the electrolyte taken out of the tank, and the powder is strongly stirred for 15 ~ 120 minutes at 30 ~ 40 ℃, and the sodium ethoxide and the sodium oxide are supplemented according to the detected amount.

The anode area of the electrolytic cell is sealed in an isolated way, and oxygen is separated by static separation or molecular sieve adsorption to recover the glycol solvent and then is led out for storage. And (3) eluting the solvent adsorbed by the molecular sieve with absolute ethyl alcohol, recovering the absolute ethyl alcohol, adding the recovered absolute ethyl alcohol into the system for use, and recycling the molecular sieve after the absolute ethyl alcohol is removed.

And replacing the cathode aluminum plate periodically, and keeping the system in a fully sealed and anhydrous state.