Synthesis method of high-purity ammonium gallium oxalate

Abstract

The invention relates to the technical field of chemical synthesis, in particular to a synthesis method of high-purity ammonium gallium oxalate, which comprises the following steps: mixing a gallium-containing solution with a hydrogen peroxide solution, then adding alkali liquor, heating and dissolving to obtain a gallium-containing alkaline solution, filtering, then adding inorganic acid into the filtrate, adjusting the pH value to 5-7, ageing and then filtering; washing the precipitate obtained by filtering with deionized water for multiple times, and adding an oxalic acid solution into the precipitate until the precipitate is completely dissolved to obtain a gallium oxalate solution; the method comprises the following steps: adding a saturated ammonium oxalate solution into a gallium oxalate solution, heating and stirring, aging after the reaction is completed, filtering to obtain an ammonium gallium oxalate crystal, washing the ammonium gallium oxalate crystal with deionized water and ethanol for several times respectively, and drying the ammonium gallium oxalate crystal in vacuum to obtain the high-purity ammonium gallium oxalate, the synthetic method fills the blank of the synthetic method of the high-purity ammonium gallium oxalate, and the synthetic method is simple in operation process and low in cost. And the synthesized ammonium gallium oxalate has high purity and is suitable for large-scale industrial production.

Description

Technical Field

[0001] The invention relates to the technical field of chemical synthesis, and in particular to a method for synthesizing high-purity ammonium gallium oxalate. Background Art

[0002] Gallium (Ga) is an important supporting material for the development of contemporary information technology, and gallium compounds are widely used in the electronics industry. Ammonium gallium oxalate, as an inorganic salt of gallium, can be used in catalysts, analytical reagents, pharmaceutical materials, etc. In the existing technology, there is still a lack of a method for synthesizing high-purity ammonium gallium oxalate.

[0003] In the process of electrolytic purification of gallium, crude gallium is used as the anode, high-purity gallium is used as the cathode, and alkaline solution is used as the electrolyte. In the electrolytic process, electrolytic waste liquid containing gallium is generated. If high-purity ammonium gallium oxalate can be synthesized with the gallium-containing solution, it can not only fill the gap in the synthesis method of high-purity ammonium gallium oxalate, but also greatly reduce the production cost. In view of this, we propose a method for synthesizing high-purity ammonium gallium oxalate. Summary of the invention

[0004] The object of the present invention is to provide a method for synthesizing high-purity ammonium gallium oxalate to solve the problems raised in the above background technology.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] A method for synthesizing high-purity ammonium gallium oxalate comprises the following steps:

[0007] S1, mixing the gallium-containing solution with the hydrogen peroxide solution, then adding alkaline solution to heat and dissolve, obtaining an alkaline solution containing gallium, and filtering;

[0008] S2, adding inorganic acid to the filtrate in step S1, adjusting the pH to 5-7, and filtering after aging;

[0009] S3, washing the precipitate obtained by filtration in step S2 with deionized water for several times, adding oxalic acid solution to the precipitate until the precipitate is completely dissolved, to obtain a gallium oxalate solution;

[0010] S4, adding saturated ammonium oxalate solution to the gallium oxalate solution of step S3, heating and stirring, and aging after the reaction is completed;

[0011] S5. Filter the reaction product in step S4 to obtain ammonium gallium oxalate crystals, wash them with deionized water and ethanol for several times, and vacuum dry the ammonium gallium oxalate crystals to obtain high-purity ammonium gallium oxalate.

[0012] Preferably, in step S1, the volume fraction of hydrogen peroxide in the hydrogen peroxide solution is 35%, the amount of hydrogen peroxide solution added is 3%-10% of the volume of the gallium-containing solution, the alkali solution is potassium hydroxide or sodium hydroxide, the concentration of the alkali solution is 2-8 mol / L, the volume ratio of the alkali solution added to the gallium-containing solution is 1-5:1, and the heating temperature is 40-60°C.

[0013] Preferably, in step S2, the inorganic acid is any one of hydrochloric acid, nitric acid and sulfuric acid, the concentration of the inorganic acid is 0.5-4 mol / L, the aging temperature is 40-60° C., and the aging time is 2-5 hours.

[0014] Preferably, in step S3, the concentration of the oxalic acid solution is 4-10 mol / L.

[0015] Preferably, in step S4, the heating temperature is 40-80°C, the stirring rate is 80-200 r / min, the aging temperature is 40-80°C, and the aging time is 2-5 hours.

[0016] Preferably, in step S5, deionized water and ethanol are used for washing 3-6 times respectively, the vacuum drying temperature is 60-100° C., and the vacuum drying time is 4-12 hours.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] 1. The synthesis method of high-purity ammonium gallium oxalate comprises mixing a gallium-containing solution with a hydrogen peroxide solution, then adding an alkaline solution to heat and dissolve, obtaining an alkaline solution containing gallium, filtering, then adding an inorganic acid to the filtrate, adjusting the pH to 5-7, aging and filtering; washing the precipitate obtained by filtration with deionized water for several times, adding an oxalic acid solution to the precipitate until the precipitate is completely dissolved, obtaining a gallium oxalate solution; adding a saturated ammonium oxalate solution to the gallium oxalate solution, heating and stirring, aging after the reaction is completed, filtering, obtaining ammonium gallium oxalate crystals, and vacuum drying the ammonium gallium oxalate crystals to obtain high-purity ammonium gallium oxalate. The synthesis method fills the gap in the synthesis method of high-purity ammonium gallium oxalate, and the operation process is simple, and the synthesized ammonium gallium oxalate has high purity.

[0019] 2. The synthesis method of high-purity ammonium gallium oxalate uses a gallium-containing solution as a synthetic raw material, and the added reaction reagents are commonly used reagents, which has low cost and is suitable for large-scale industrial production. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 The present invention is a flow chart of the synthesis method of high-purity ammonium gallium oxalate. DETAILED DESCRIPTION

[0021] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0022] See also Figure 1 As shown, a technical solution provided by the present invention is:

[0023] Example 1

[0024] A method for synthesizing high-purity ammonium gallium oxalate comprises the following steps:

[0025] S1. Mix the gallium-containing solution with a 35% volume fraction hydrogen peroxide solution, the amount of hydrogen peroxide solution added is 3% of the volume of the gallium-containing solution, then add 2 mol / L alkali solution and heat to dissolve, the volume ratio of the alkali solution added to the gallium-containing solution is 5:1, the heating temperature is 40°C, and a gallium-containing alkaline solution is obtained, which is filtered;

[0026] S2, add 0.5 mol / L hydrochloric acid to the filtrate in step S1, adjust the pH to 5, filter after aging, the aging temperature is 40° C., and the aging time is 2 hours;

[0027] S3, washing the precipitate obtained by filtration in step S2 with deionized water for several times, adding 4 mol / L oxalic acid solution to the precipitate until the precipitate is completely dissolved, to obtain a gallium oxalate solution;

[0028] S4, adding saturated ammonium oxalate solution to the gallium oxalate solution of step S3, heating and stirring, the heating temperature is 40°C, the stirring rate is 80r / min, and aging after the reaction is completed, the aging temperature is 40°C, and the aging time is 2 hours;

[0029] S5. Filter the reaction product in step S4 to obtain ammonium gallium oxalate crystals, wash with deionized water and ethanol three times respectively, and vacuum dry the ammonium gallium oxalate crystals at a vacuum drying temperature of 60° C. for 12 hours to obtain high-purity ammonium gallium oxalate.

[0030] The purity of the ammonium gallium oxalate obtained in this example is 99.92%.

[0031] Example 2

[0032] A method for synthesizing high-purity ammonium gallium oxalate comprises the following steps:

[0033] S1. Mix the gallium-containing solution with a 35% volume fraction of hydrogen peroxide solution, the amount of hydrogen peroxide solution added is 5% of the volume of the gallium-containing solution, then add 4 mol / L alkali solution and heat to dissolve, the volume ratio of the alkali solution added to the gallium-containing solution is 4:1, the heating temperature is 45°C, and a gallium-containing alkaline solution is obtained, which is filtered;

[0034] S2, add 1 mol / L nitric acid to the filtrate in step S1, adjust the pH to 5, filter after aging, the aging temperature is 45° C., and the aging time is 3 hours;

[0035] S3, washing the precipitate obtained by filtration in step S2 with deionized water for several times, adding 6 mol / L oxalic acid solution to the precipitate until the precipitate is completely dissolved, to obtain a gallium oxalate solution;

[0036] S4, adding saturated ammonium oxalate solution to the gallium oxalate solution of step S3, heating and stirring, the heating temperature is 50° C., the stirring rate is 120 r / min, and aging after the reaction is completed, the aging temperature is 50° C., and the aging time is 3 hours;

[0037] S5. Filter the reaction product in step S4 to obtain ammonium gallium oxalate crystals, wash them with deionized water and ethanol four times respectively, and vacuum dry the ammonium gallium oxalate crystals at a vacuum drying temperature of 70° C. for 10 hours to obtain high-purity ammonium gallium oxalate.

[0038] The purity of the ammonium gallium oxalate obtained in this example is 99.94%.

[0039] Example 3

[0040] A method for synthesizing high-purity ammonium gallium oxalate comprises the following steps:

[0041] S1. Mix the gallium-containing solution with a 35% volume fraction hydrogen peroxide solution, wherein the amount of the hydrogen peroxide solution added is 8% of the volume of the gallium-containing solution, and then add 6 mol / L alkali solution to heat and dissolve, wherein the volume ratio of the alkali solution added to the gallium-containing solution is 3:1, and the heating temperature is 50° C. to obtain a gallium-containing alkaline solution, which is filtered;

[0042] S2, add 2 mol / L sulfuric acid to the filtrate in step S1, adjust the pH to 6, filter after aging, the aging temperature is 50° C., and the aging time is 4 hours;

[0043] S3, washing the precipitate obtained by filtration in step S2 with deionized water for several times, adding 8 mol / L oxalic acid solution to the precipitate until the precipitate is completely dissolved, to obtain a gallium oxalate solution;

[0044] S4, adding saturated ammonium oxalate solution to the gallium oxalate solution of step S3, heating and stirring, the heating temperature is 70°C, the stirring rate is 150r / min, and aging after the reaction is completed, the aging temperature is 70°C, and the aging time is 4 hours;

[0045] S5. Filter the reaction product in step S4 to obtain ammonium gallium oxalate crystals, wash them with deionized water and ethanol for 5 times respectively, and vacuum dry the ammonium gallium oxalate crystals at a vacuum drying temperature of 85° C. for 6 hours to obtain high-purity ammonium gallium oxalate.

[0046] The purity of the ammonium gallium oxalate obtained in this example is 99.93%.

[0047] Example 4

[0048] A method for synthesizing high-purity ammonium gallium oxalate comprises the following steps:

[0049] S1. Mix the gallium-containing solution with a 35% volume fraction hydrogen peroxide solution, wherein the amount of the hydrogen peroxide solution added is 10% of the volume of the gallium-containing solution, and then add 8 mol / L alkali solution to heat and dissolve, wherein the volume ratio of the alkali solution added to the gallium-containing solution is 1:1, and the heating temperature is 60° C. to obtain a gallium-containing alkaline solution, which is filtered;

[0050] S2, add 4 mol / L hydrochloric acid to the filtrate in step S1, adjust the pH to 7, filter after aging, the aging temperature is 60° C., and the aging time is 5 hours;

[0051] S3, washing the precipitate obtained by filtration in step S2 with deionized water for several times, adding 10 mol / L oxalic acid solution to the precipitate until the precipitate is completely dissolved, to obtain a gallium oxalate solution;

[0052] S4, adding saturated ammonium oxalate solution to the gallium oxalate solution of step S3, heating and stirring, the heating temperature is 80°C, the stirring rate is 200r / min, and aging after the reaction is completed, the aging temperature is 80°C, and the aging time is 5 hours;

[0053] S5. Filter the reaction product in step S4 to obtain ammonium gallium oxalate crystals, wash with deionized water and ethanol for 6 times respectively, and vacuum dry the ammonium gallium oxalate crystals at a vacuum drying temperature of 100° C. for 4 hours to obtain high-purity ammonium gallium oxalate.

[0054] The purity of the ammonium gallium oxalate obtained in this example is 99.95%.

[0055] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above embodiments. The above embodiments and descriptions are only preferred examples of the present invention and are not intended to limit the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A method for synthesizing high-purity ammonium gallium oxalate, characterized in that: The following steps are involved: S1, mixing the gallium-containing solution with the hydrogen peroxide solution, then adding alkaline solution to heat and dissolve, obtaining an alkaline solution containing gallium, and filtering; S2, adding inorganic acid to the filtrate in step S1, adjusting the pH to 5-7, and filtering after aging; S3, washing the precipitate obtained by filtration in step S2 with deionized water for several times, adding oxalic acid solution to the precipitate until the precipitate is completely dissolved, to obtain a gallium oxalate solution; S4, adding saturated ammonium oxalate solution to the gallium oxalate solution of step S3, heating and stirring, and aging after the reaction is completed; S5. Filter the reaction product in step S4 to obtain ammonium gallium oxalate crystals, wash them with deionized water and ethanol for several times, and vacuum dry the ammonium gallium oxalate crystals to obtain high-purity ammonium gallium oxalate.

2. The method for synthesizing high-purity ammonium gallium oxalate according to claim 1, characterized in that: In step S1, the volume fraction of hydrogen peroxide in the hydrogen peroxide solution is 35%, the amount of hydrogen peroxide solution added is 3%-10% of the volume of the gallium-containing solution, the alkali solution is potassium hydroxide or sodium hydroxide, the concentration of the alkali solution is 2-8 mol / L, the volume ratio of the alkali solution added to the gallium-containing solution is 1-5:1, and the heating temperature is 40-60°C.

3. The method for synthesizing high-purity ammonium gallium oxalate according to claim 1, characterized in that: In step S2, the inorganic acid is any one of hydrochloric acid, nitric acid and sulfuric acid, the concentration of the inorganic acid is 0.5-4 mol / L, the aging temperature is 40-60° C., and the aging time is 2-5 hours.

4. The method for synthesizing high-purity ammonium gallium oxalate according to claim 1, characterized in that: In step S3, the concentration of the oxalic acid solution is 4-10 mol / L.

5. The method for synthesizing high-purity ammonium gallium oxalate according to claim 1, characterized in that: In the step S4, the heating temperature is 40-80°C, the stirring rate is 80-200r / min, the aging temperature is 40-80°C, and the aging time is 2-5 hours.

6. The method for synthesizing high-purity ammonium gallium oxalate according to claim 1, characterized in that: In the step S5, the deionized water and ethanol are used for washing 3-6 times respectively, the vacuum drying temperature is 60-100° C., and the vacuum drying time is 4-12 hours.

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