Background technology
Adopting resin method to reclaim gallium is one of state-of-the-art method in current all gallium production methods, gallium finally obtains by electrolysis gallium salt brine solution, owing to the resin choice reason, the content of vanadium that causes electrolytic solution is than higher, make its actual electrolysis deposition potential exceed the deposition potential of gallium, cause the preferential reduction of vanadium in the electrolytic process, make the pole plate blackout, reduced the overpotential of hydrogen evolution, so that cause gallium on pole plate, to deposit difficulty, problems such as current efficiency is low are seriously restricting the further raising of quality and output.
Vanadium exists with the vanadic acid sodium form in electrolytic solution, owing to produce oxygen continuously on the anode in the electrolytic solution, owing to electrochemical reason, make vanadium on electrolytic solution and pole plate, produce the circulation change of valence state, consumed electric energy, influenced gallium separating out at negative electrode, even gallium can come out in electrolysis, and is also too much because of the sponge gallium, quality can not get guaranteeing, also need to handle the sponge gallium more again, obtain qualified gallium.With the milk of lime vanadium removal can only be lower at the mother liquor free alkali concentration (NaOH content≤100g/l) down effectively, and can cause the greater loss of gallium.The high more vanadium removal effect of free alkali concentration is poor more, how therefrom effectively vanadium to be removed under the situation of not losing gallium content in the electrolytic solution, is the problem that presses for solution in producing at present.Resolve vanadium in the electrolytic solution remove technology after, not only can improve the output of gallium greatly, reduce the cost of unit gallium because vanadium is removed in the electrolytic solution, the electrolysis lean liquor just can the Returning process repeated use, has reduced production cost.
Summary of the invention
The object of the present invention is to provide the vanadium removal method of electrolytic solution in a kind of gallium electrolysis production, reduce the content of vanadium in the electrolytic solution, improve Faradaic current efficient and production capacity that resin method extracts gallium, can make the electrolysis lean liquor obtain recycling, reduce production costs.
The vanadium removal method of electrolytic solution in the gallium electrolysis production of the present invention, carry out according to the following step successively:
Reaction system is: 1.5~5CaOAl
2O
32~5.8V
2O
54~19H
2O;
(1) in electrolytic solution, adds hydrogen peroxide, make S wherein
2-Be oxidized to SO
4 2-
(2) add aluminium hydroxide in the electrolytic solution after oxidation, make solution oxide aluminium content reach 2~50g/l;
(3) add white lime in above-mentioned solution and reach 5~100g/l, violent stirring is 8~12 hours under 50~60 ℃ temperature, carries out the vanadium removal reaction;
(4) solution temperature is reduced to 20~40 ℃, implements solid-liquid separation, go out vanadium slag, obtain the electrolytic solution of vanadium low levels.
Wherein, the add-on of hydrogen peroxide is that 8~12% of electrolytic solution volume suits, and the concentration of hydrogen peroxide is chosen as 50%.
The solvent temperature of aluminium hydroxide preferably is controlled to be: 100~120 ℃
The vanadium removal methodological science of electrolytic solution is reasonable in the gallium electrolysis production of the present invention, simple, can be with the content of vanadium in the electrolytic solution (NaOH content is at 250g/l-300g/l) of high alkalinity from dropping to more than the 1000mg/l below the 40mg/l, satisfy the demand of gallium electrolysis process, by reducing the content of vanadium in the electrolytic solution, improved resin method and extracted the Faradaic current efficient and the production capacity of gallium, and can make the electrolysis lean liquor obtain recycling, reduced production costs.
Embodiment
The invention will be further described below in conjunction with embodiment.
Embodiment 1
The vanadium removal method of electrolytic solution in the gallium electrolysis production of the present invention, carry out according to the following step successively:
Reaction system is: 3CaOAl
2O
34V
2O
510H
2O;
(1) adding volume ratio in the electrolytic solution that contains NaOH 253g/l is 10% 50% hydrogen peroxide, makes S wherein
2-Be oxidized to SO
4 2-
(2) add aluminium hydroxide in the electrolytic solution after oxidation, be warmed up to 110 ± 3 ℃ of dissolvings, make solution oxide aluminium content reach 30g/l;
(3) in above-mentioned solution, add white lime [Ca (OH)
2] 50g/l, under 55 ± 3 ℃ temperature, carried out violent stirring 10 hours, carry out the vanadium removal reaction;
(4) solution temperature is reduced to 25 ± 3 ℃, implements solid-liquid separation, go out vanadium slag, obtain the electrolytic solution of vanadium low levels, the content of vanadium is reduced to 28mg/l by 1146mg/l.
Embodiment 2
The vanadium removal method of electrolytic solution in the gallium electrolysis production of the present invention, carry out according to the following step successively:
Reaction system is: 2.5CaOAl
2O
34.5V
2O
512H
2O;
(1) adding volume ratio in the electrolytic solution that contains NaOH 266g/l is 11% 50% hydrogen peroxide, makes S wherein
2-Be oxidized to SO
4 2-
(2) add aluminium hydroxide in the electrolytic solution after oxidation, be warmed up to 105 ± 3 ℃ of dissolvings, make solution oxide aluminium content reach 23g/l;
(3) add white lime in above-mentioned solution and reach 45g/l, violent stirring is 9 hours under 55 ± 2 ℃ temperature, carries out the vanadium removal reaction;
(4) solution temperature is reduced to 25 ± 3 ℃, implements solid-liquid separation, remove vanadium slag, obtain the electrolytic solution of vanadium low levels, the content of vanadium is reduced to 38mg/l by 1295mg/l.
Embodiment 3
The vanadium removal method of electrolytic solution in the gallium electrolysis production of the present invention, carry out according to the following step successively:
Reaction system is: 5CaOAl
2O
35V
2O
58H
2O;
(1) adding volume ratio in the electrolytic solution that contains NaOH 256g/l is 10% 50% hydrogen peroxide, makes S wherein
2-Be oxidized to SO
4 2-
(2) add aluminium hydroxide in the electrolytic solution after oxidation, be warmed up to 160 ± 3 ℃ of dissolvings, make solution oxide aluminium content reach 40g/l;
(3) add white lime in above-mentioned solution and reach 30g/l, violent stirring is 8.5 hours under 53 ± 3 ℃ temperature, carries out the vanadium removal reaction;
(4) solution temperature is reduced to 35 ± 3 ℃, implements solid-liquid separation, remove vanadium slag, obtain the electrolytic solution of vanadium low levels, the content of vanadium is reduced to 36mg/l by 1270mg/l.
Embodiment 4
The vanadium removal method of electrolytic solution in the gallium electrolysis production of the present invention, carry out according to the following step successively:
Reaction system is: 4CaOAl
2O
33V
2O
515H
2O;
(1) adding volume ratio in the electrolytic solution that contains NaOH 280g/l is 9% 50% hydrogen peroxide, makes S wherein
2-Be oxidized to SO
4 2-
(2) add aluminium hydroxide in the electrolytic solution after oxidation, be warmed up to 112 ± 3 ℃ of dissolvings, make solution oxide aluminium content reach 36g/l;
(3) add white lime in above-mentioned solution and reach 55g/l, violent stirring is 12 hours under 56 ± 3 ℃ temperature, carries out the vanadium removal reaction;
(4) solution temperature is reduced to 30 ± 3 ℃, implements solid-liquid separation, remove vanadium slag, obtain the electrolytic solution of vanadium low levels, the content of vanadium is reduced to 37mg/l by 1260mg/l.
Embodiment 5
The vanadium removal method of electrolytic solution in the gallium electrolysis production of the present invention, carry out according to the following step successively:
Reaction system is: 2CaOAl
2O
33.5V
2O
514H
2O;
(1) adding volume ratio in the electrolytic solution that contains NaOH 262g/l is 10% 50% hydrogen peroxide, makes S wherein
2-Be oxidized to SO
4 2-
(2) add aluminium hydroxide in the electrolytic solution after oxidation, be warmed up to 115 ± 3 ℃ of dissolvings, make solution oxide aluminium content reach 32g/l;
(3) add white lime in above-mentioned solution and reach 50g/l, violent stirring is 9 hours under 54 ± 3 ℃ temperature, carries out the vanadium removal reaction;
(4) solution temperature is reduced to 33 ± 3 ℃, implements solid-liquid separation, remove vanadium slag, obtain the electrolytic solution of vanadium low levels.
Embodiment 6
The vanadium removal method of electrolytic solution in the gallium electrolysis production of the present invention, carry out according to the following step successively:
Reaction system is: 4.2CaOAl
2O
33.6V
2O
512H
2O;
(1) adding volume ratio in the electrolytic solution that contains NaOH 260g/l is 12% 50% hydrogen peroxide, makes S wherein
2-Be oxidized to SO
4 2-
(2) add aluminium hydroxide in the electrolytic solution after oxidation, be warmed up to 117 ± 3 ℃ of dissolvings, make solution oxide aluminium content reach 28g/l;
(3) add white lime in above-mentioned solution and reach 70g/l, violent stirring is 11 hours under 55 ± 3 ℃ temperature, carries out the vanadium removal reaction;
(4) solution temperature is reduced to 32 ± 3 ℃, implements solid-liquid separation, remove vanadium slag, obtain the electrolytic solution of vanadium low levels.