Hydrogen peroxide tail gas absorption liquid based on germanium dioxide efficient settlement and recycling process and application

Abstract

This invention discloses a high-efficiency sedimentation and recycling process and application of germanium dioxide in hydrogen peroxide tail gas absorbent, belonging to the field of industrial waste gas treatment and rare dispersed metal recovery technology in the specialty gas industry. The process includes: static separation of the hydrogen peroxide tail gas absorbent; efficient sedimentation of germanium dioxide by synergistic adjustment of pH and composite flocculant in the sedimentation layer; dehydration of the concentrated germanium dioxide phase to form a filter cake, followed by three-stage countercurrent washing and staged heating drying to obtain crude germanium dioxide solid; and a three-stage purification system for the filtrate and supernatant after sedimentation, consisting of primary pH adjustment, secondary membrane separation adsorption, and tertiary closed-loop hydrogen peroxide replenishment, to achieve efficient recycling of hydrogen peroxide. This results in a germanium dioxide recovery rate of over 99%, a hydrogen peroxide recovery rate of over 95%, and a reduction in process cost of over 40%. The process is simple, has high resource recovery rate, and low operating cost, and is suitable for the treatment and resource utilization of germanium-containing tail gas in semiconductor, photovoltaic material, and specialty gas production.

Description

Technical Field

[0001] This invention relates to the field of industrial waste gas treatment and rare dispersed metal recovery technology in the specialty gas industry, and particularly to a process and application of efficient sedimentation and recycling of germanium dioxide in hydrogen peroxide tail gas absorbent. Background Technology

[0002] Germanium is an important semiconductor material, possessing properties of both metals and non-metals. It boasts advantages such as low electrical resistance, zero heat loss, and low power consumption, making it an indispensable key material in the modern information industry. According to the 2023 annual report of the International Germanium Development Association (IGDA), germanium applications are diversified globally, with optical fibers accounting for 34% (primarily used in 5G optical fiber preform manufacturing), infrared optics for 36%, polymerization catalysts for 4%, electronics and photovoltaics for 17%, and other applications for 9%.

[0003] Germanium dioxide, as a core precursor material, plays an irreplaceable role in the electronics and photovoltaic fields. Market data shows that global consumption of high-purity germanium dioxide reached 180 tons in 2023; it is projected to exceed 220 tons by 2025, with a compound annual growth rate of 8.7%. However, germanium is classified as a "critical metal." Currently, approximately 60% of global germanium supply relies on zinc smelting byproducts, and 30% depends on recycling systems, posing a severe challenge to the security of germanium resources.

[0004] In the semiconductor and photovoltaic manufacturing industries, germane is an important gas source for chemical deposition (CVD) processes. Its tail gas treatment faces significant technical challenges. Currently, the industrial treatment solutions mainly fall into three categories: (1) Traditional combustion method, which is simple to operate but has low conversion rate and selectivity, resulting in low germanium recovery capacity; (2) Wet alkaline absorption method, which can effectively improve germanium recovery rate to 75-80%. During the recovery process, complex germanate complexes are formed, subsequent separation steps are cumbersome, and high-salt wastewater is generated, leading to a sharp increase in treatment costs; (3) Hydrogen peroxide absorption method is the current mainstream technology in the industry. This method is mild, safe, and highly selective (its conversion rate is above 98%), but it still has limitations in industrial applications. In the 10% hydrogen peroxide system, germanium dioxide colloid settles slowly, and hydrogen peroxide itself is decomposable, increasing the cost of tail gas treatment.

[0005] According to data from the "2023 Blue Book on Rare and Dispersed Metals Industry" by the China Nonferrous Metals Industry Association, the germanium metal loss rate in germanium recycling processes is 12-15%, mainly due to: germanium metal loss in colloidal form during sedimentation and low adsorption capacity, resulting in low germanium capture efficiency. This situation exacerbates the germanium metal supply risk and increases the environmental costs for enterprises. Therefore, developing germanium dioxide recovery technologies with advantages such as simple processes, high recovery rates, and low operating costs has significant economic value and importance. Summary of the Invention

[0006] This invention provides a process and application for efficient sedimentation and recycling of germanium dioxide in hydrogen peroxide tail gas absorption liquid to overcome the above-mentioned problems.

[0007] To achieve the above objectives, the technical solution of the present invention is as follows:

[0008] This invention provides a highly efficient sedimentation and recycling process for germanium dioxide in hydrogen peroxide tail gas absorbent, comprising the following steps:

[0009] S1: Pass the tail gas absorption liquid in the spray tower into the settling tank and let it stand for 2-4 hours. Pass the top supernatant into the supernatant overflow tank and the bottom settling layer into the settling zone.

[0010] S2: After adjusting the pH of the sedimentation layer in the sedimentation inner zone with nitric acid, a composite flocculant is added, stirred, and allowed to stand to obtain germanium dioxide concentrated slurry. The obtained germanium dioxide concentrated slurry is then filtered through a filter press to obtain filter cake and filtrate respectively.

[0011] S3: The filter cake from S2 is subjected to a three-stage countercurrent washing process to remove residual hydrogen peroxide and soluble salts from the filter cake. The washing water is deionized water.

[0012] S4: The filter cake washed in S3 is dried by staged heating to obtain crude solid germanium dioxide;

[0013] S5: Combine the supernatant obtained in S1 and the filtrate obtained in S2 into a mixed solution. Adjust the pH of the mixed solution with nitric acid, add hydrogen peroxide as a stabilizer, and then adsorb and remove germanium and Fe from the mixed solution. 2+ / Cu 2+ Metal ions;

[0014] S6: The liquid obtained after adsorption treatment of the mixture in S5 is subjected to ultrafiltration to remove colloidal germanium and suspended solids other than colloidal germanium in the liquid. The purified liquid is then introduced into the absorption liquid circulation tank.

[0015] S7: Monitor the concentration of hydrogen peroxide in the absorption liquid circulation tank, add hydrogen peroxide according to the monitored concentration until the concentration of hydrogen peroxide in the circulation tank reaches the set value, and then pass it into the spray tower in the tail gas system for recycling.

[0016] Furthermore, in S2, the concentration of nitric acid is 5-10%, and the pH of the sedimentation layer is adjusted to 2.0-5.0.

[0017] Further, in S2, the composite flocculant is a composite of anionic polyacrylamide APAM and polyaluminum chloride PAC, wherein the dosage of APAM is 1.0~2.0 ppm and the dosage of PAC is 10~30 ppm;

[0018] The specific method for stirring and settling is as follows: stir at 100~150 rpm for 30 minutes and let stand for 2~5 hours.

[0019] Furthermore, in S3, in the three-stage countercurrent washing process, the mass ratio of deionized water to filter cake is 3:1 to 5:1, and the temperature of the deionized water is 50 to 80 ℃.

[0020] Further, in S5, the concentration of nitric acid is 5-10%, and the pH of the mixture is adjusted to 3.0-5.0; the hydrogen peroxide stabilizer is disodium EDTA, and the amount added is 1% of the volume of the mixture.

[0021] Further, in S5, the adsorption method is as follows: the mixture is passed sequentially through a fixed-bed ion exchange column and a chelating resin column to remove germanium and Fe from the mixture, respectively. 2+ / Cu 2+ Metal ions; the fixed bed ion exchange column uses D403 chelating resin, and the chelating resin column uses Chelex 100.

[0022] Furthermore, in S4, the staged heating and drying method is as follows: the obtained filter cake is successively heated and dried at 60 ℃, 80 ℃, 100 ℃, and 120 ℃ for 2 hours, 2 hours, 2 hours, and 4 hours respectively.

[0023] Furthermore, in S6, the ultrafiltration operation to retain colloidal germanium in the liquid is performed by using a sulfonated polyether ether ketone SPEEK membrane with a molecular weight cutoff of 10 kDa and operating at a pressure of 0.1~0.3 MPa.

[0024] Furthermore, in S7, the concentration of hydrogen peroxide in the absorption liquid circulation tank is monitored by an online ORP sensor, and a 30% hydrogen peroxide solution is added by an interlocking metering pump. After adding the hydrogen peroxide solution, the concentration of hydrogen peroxide in the absorption liquid circulation tank reaches 10±0.5% for subsequent recycling.

[0025] Another aspect of the present invention provides an application of a high-efficiency sedimentation and recycling process for germanium dioxide in hydrogen peroxide tail gas absorbent liquid in the purification and resource recovery of germanium-containing tail gas in semiconductor wafer manufacturing, photovoltaic cell material production, optical fiber preform preparation, and special gas production processes.

[0026] The beneficial effects of this invention are:

[0027] (1) The present invention discloses a high-efficiency sedimentation and recycling process for germanium dioxide in hydrogen peroxide tail gas absorption liquid. First, the pH of the sedimentation layer is adjusted by nitric acid, and then it is combined with a composite flocculant to form a dense floc with a three-dimensional network structure in the sedimentation layer, shortening the sedimentation time to within 4.5 hours. The solid content of the concentrated mud is ≥30%, achieving high-efficiency primary enrichment of germanium dioxide. At the same time, the innovative three-stage countercurrent washing process and staged heating method are used to treat the filter cake, which saves more than 40% of water compared with the traditional process, avoids the crystal transformation of germanium dioxide, and obtains crude germanium dioxide solid with a product purity of more than 99.0%.

[0028] (2) This process utilizes the hydrogen peroxide closed-loop regeneration process and the germanium dioxide high-efficiency deposition and recovery process to form a synergistic optimization. Through a three-stage purification system, the hydrogen peroxide in the hydrogen peroxide tail gas absorption liquid is efficiently recycled. This process performs first-stage pH adjustment, second-stage membrane separation adsorption and third-stage closed-loop replenishment of hydrogen peroxide on the filtrate and supernatant in sequence to complete the efficient recycling of hydrogen peroxide, achieving a hydrogen peroxide recycling rate of up to 95%, while reducing hydrogen peroxide consumption by 45%. This provides an innovative solution with both economic and environmental benefits for the rare and dispersed metal recycling industry. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0030] Figure 1 This is a flow chart of a process for efficient sedimentation and recycling of germanium dioxide in hydrogen peroxide tail gas absorption liquid, as disclosed in an embodiment of the present invention. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0032] In the hydrogen peroxide tail gas absorption liquid targeted by this invention, the germanium concentration in the original solution generally ranges from 10 to 500 ppm; in addition, due to equipment corrosion and impurities, the main metal ions in the tail gas absorption liquid are iron (Fe). 2+ and copper Cu2+ Its concentration range is typically 1-50 ppm, with the specific concentration varying depending on the source of the exhaust gas and the process conditions.

[0033] Example 1:

[0034] A process for efficient sedimentation and recycling of germanium dioxide in hydrogen peroxide tail gas absorbent is described in the flowchart below. Figure 1 As shown, it includes the following steps:

[0035] S1: Pass the tail gas absorption liquid in the spray tower into the settling tank for 4 hours, pass the supernatant at the top into the clear liquid overflow tank, and pass the bottom settling layer into the settling zone through the bottom pump.

[0036] S2: After adjusting the pH of the sedimentation layer in the sedimentation inner zone to 3.0 with 10% nitric acid, 0.5 ppm anionic polyacrylamide APAM and 20 ppm polyaluminum chloride PAC were added. The mixture was stirred at 150 rpm for 30 min and allowed to stand for 4.5 hours to obtain germanium dioxide concentrated slurry with a solid content of 15.6%. The germanium dioxide concentrated slurry was filtered through a filter press to obtain filter cake and filtrate.

[0037] S3: The obtained filter cake is washed in a three-stage countercurrent process at a water temperature of 60℃ with a deionized water to filter cake mass ratio of 5:1 (i.e., three washing units (washing tanks) connected in series, with the filter cake to be washed flowing in the opposite direction to the deionized water) to remove residual hydrogen peroxide and soluble salts from the filter cake, reducing water costs by 15%.

[0038] S4: The washed filter cake was sequentially dried at 60℃, 80℃, 100℃, and 120℃ for 2 hours, 2 hours, 2 hours, and 4 hours respectively to obtain crude solid germanium dioxide. The purity of the crude germanium dioxide was 98.4%, and the germanium recovery rate was 92.8%.

[0039] S5: Combine the filtrate obtained in S2 with the overflow tank containing the supernatant obtained in S1 to obtain a mixed solution. Adjust the pH of the mixed solution to 3.0 with 10% nitric acid, then add 1% (by volume) of disodium EDTA. Stir at 80 rpm for 10 min, then pass the mixture sequentially through a fixed-bed ion exchange column (D403 type resin) and a chelating resin column (Chelex 100) to adsorb and remove germanium and Fe from the mixed solution. 2+ / Cu 2+ Metal ions (Fe) 2+ and Cu 2+ After adsorption, the germanium concentration in the liquid at the outlet is <0.1 ppm, and the Fe concentration is <0.1 ppm. 2+ / Cu 2+ Residue <0.02 ppm, hydrogen peroxide decomposition rate <0.10%;

[0040] S6: The liquid obtained after adsorption treatment of the mixture in S5 is subjected to ultrafiltration using a sulfonated polyether ether ketone (SPEEK) membrane with a molecular weight cutoff of 10 kDa and an operating pressure of 0.3 MPa. Colloidal germanium and other suspended solids in the liquid are retained. The purified liquid after retention enters the absorption liquid circulation tank. The service life of the sulfonated polyether ether ketone (SPEEK) membrane (ion exchange membrane) is 12 months, which is 3 times longer and the annual maintenance cost is reduced by 30%.

[0041] S7: The hydrogen peroxide concentration is monitored by an online ORP sensor. At the same time, the interlocking metering pump adds 30% hydrogen peroxide solution until the concentration of the circulating liquid is 10±0.5%, the hydrogen peroxide utilization rate is 95%, and the annual operating cost is reduced by 45%.

[0042] Example 2

[0043] S1: The steps are the same as step S1 in Example 1;

[0044] S2: After adjusting the pH of the sedimentation layer in the sedimentation inner zone to 3.0 with 10% dilute nitric acid, add 1.0 ppm APAM and 20 ppm PAC, stir at 150 rpm for 30 min, and let stand for 4 hours to obtain germanium dioxide concentrated slurry with a solid content of 30.2%. The concentrated slurry is filtered through a filter press to obtain filter cake and filtrate.

[0045] S3: The obtained filter cake is washed in three stages at a water temperature of 60℃ with a deionized water to filter cake mass ratio of 4:1, which reduces water cost by 25%.

[0046] S4: The washed filter cake was successively dried at 60℃, 80℃, 100℃, and 120℃ for 2h, 2h, 2h, and 4h respectively to obtain crude solid germanium dioxide. The purity of the crude germanium dioxide was 98.6%, and the germanium recovery rate was 99.1%.

[0047] S5: Combine the filtrate obtained in S2 with the supernatant obtained in S1 in the overflow tank to obtain a mixed solution. Adjust the pH of the mixed solution to 2.0 with 10% nitric acid. Add 1% (by volume) of disodium EDTA to the mixed solution. Stir at 80 rpm for 10 min, then pass the mixture sequentially through a fixed-bed ion exchange column and a chelating resin column to adsorb and remove germanium and Fe from the mixed solution. 2+ / Cu 2+ Metal ions (Fe) 2+ and Cu 2+ After adsorption, the germanium concentration in the liquid at the outlet is <0.1 ppm, and the Fe concentration is <0.1 ppm. 2+ / Cu 2+ Residue <0.05ppm, hydrogen peroxide decomposition rate <0.10%;

[0048] S6: The steps are the same as step S6 in Example 1;

[0049] S7: The steps are the same as step S7 in Example 1.

[0050] Example 3

[0051] S1: The steps are the same as step S1 in Example 1;

[0052] S2: After adjusting the pH of the sedimentation layer in the sedimentation inner zone to 3.0 with 10% dilute nitric acid, add 2.0 ppm APAM and 20 ppm PAC, stir at 150 rpm for 30 min, and let stand for 4 hours to obtain germanium dioxide concentrated slurry with a solid content of 30.2%. The concentrated slurry is filtered through a filter press to obtain filter cake and filtrate.

[0053] S3: The obtained filter cake is washed in three stages at a water temperature of 60℃ with a deionized water to filter cake mass ratio of 3:1, which reduces water costs by 40%.

[0054] S4: The washed filter cake was successively heated and dried at 60℃, 80℃, 100℃, and 120℃ for 2h, 2h, 2h, and 4h respectively to obtain crude solid germanium dioxide. The purity of the crude germanium dioxide was 99.1%, and the germanium recovery rate was 98.2%.

[0055] S5: Combine the filtrate obtained in S2 with the overflow tank containing the supernatant obtained in S1 to obtain a mixed solution. Adjust the pH of the mixed solution to 4.0 with 10% nitric acid. Add 1% (by volume) of disodium EDTA to the mixed solution. Stir at 80 rpm for 10 min, then pass the mixture sequentially through a fixed-bed ion exchange column and a chelating resin column to adsorb and remove germanium and Fe from the mixed solution. 2+ / Cu 2+ Metal ions (Fe) 2+ and Cu 2+ After adsorption, the germanium concentration in the liquid at the outlet is <0.1 ppm, and the Fe concentration is <0.1 ppm. 2+ / Cu 2+ Residue <0.02ppm, hydrogen peroxide decomposition rate <0.10%;

[0056] S6: The steps are the same as step S6 in Example 1;

[0057] S7: The steps are the same as step S7 in Example 1.

[0058] Example 4

[0059] S1: The steps are the same as step S1 in Example 1;

[0060] S2: After adjusting the pH of the sedimentation layer in the sedimentation inner zone to 5.0 with 10% dilute nitric acid, add 1.0 ppm APAM and 20 ppm PAC, stir at 150 rpm for 30 min, and let stand for 4 hours to obtain germanium dioxide concentrated slurry with a solid content of 27.1%. The concentrated slurry is filtered through a filter press to obtain filter cake and filtrate.

[0061] S3: The steps are the same as step S3 in Example 3;

[0062] S4: The steps are the same as step S4 in Example 3, and the germanium recovery rate is 91.7%;

[0063] There are no steps S5-S7.

[0064] Comparative Example 1

[0065] S1: The steps are the same as step S1 in Example 1;

[0066] S2: Without adjusting the pH, only 1 ppm of APAM is added as flocculant, stirred at 150 rpm for 30 min, and allowed to stand for 7 hours to obtain germanium dioxide concentrated slurry with a solid content of 18.6%. The concentrated slurry is filtered through a filter press to obtain filter cake and filtrate.

[0067] S3: The steps are the same as step S3 in Example 1;

[0068] S4: The steps are the same as step S4 in Example 1, and the germanium recovery rate is 83.9%;

[0069] S5: Combine the filtrate obtained in S2 with the overflow tank containing the supernatant obtained in S1 to obtain a mixed solution. Without adjusting the pH, add 1% (by volume) of EDTA disodium hydrogen peroxide stabilizer to the mixed solution. After stirring at 80 rpm for 10 min, pass the mixture sequentially through a fixed-bed ion exchange column and a chelating resin column. The germanium concentration in the liquid at the outlet should be <0.5 ppm, and the Fe concentration should be <0.5 ppm. 2+ / Cu 2+ Residue <0.2 ppm, hydrogen peroxide decomposition rate <0.30%;

[0070] S6: The liquid obtained after adsorption treatment of the mixture in S5 is subjected to ultrafiltration using a polyethersulfone (PES) membrane with a molecular weight cutoff of 30 kDa and an operating pressure of 0.4 MPa to remove colloidal germanium and other suspended solids. The purified liquid after removal enters the absorption liquid circulation tank. The service life of the polyethersulfone (PES) membrane (ion exchange membrane) is 4 months.

[0071] S7: The steps are the same as step S7 in Example 1.

[0072] Comparative Example 2

[0073] S1: The steps are the same as step S1 in Example 3;

[0074] S2: Without adjusting the pH, only 20 ppm of PAC flocculant was added, stirred at 150 rpm for 30 min, and allowed to stand for 7 hours to obtain germanium dioxide concentrated slurry with a solid content of 19.3%. The concentrated slurry was filtered through a filter press to obtain filter cake and filtrate.

[0075] S3: The steps are the same as step S3 in Example 3;

[0076] S4: The steps are the same as step S4 in Example 3, and the germanium recovery rate is 84.2%;

[0077] There are no steps S5-S7.

[0078] The experimental results of germanium dioxide precipitation and recovery (S1-S4) in Examples 1-4 and Comparative Examples 1-2 are shown in Table 1.

[0079] Table 1. Experimental results of germanium dioxide sedimentation and recovery in Examples 1-4 and Comparative Examples 1-2.

[0080]

[0081] The experimental results of hydrogen peroxide recovery and regeneration (S1-S7) in Examples 1-3 and Comparative Example 1 are shown in Table 2.

[0082] Table 2. Experimental results of hydrogen peroxide recovery and regeneration in Examples 1-3 and Comparative Example 1.

[0083]

[0084] Results Analysis: As shown in Table 1, compared with Comparative Examples 1-2, Examples 1-4, using the composite flocculant system and pH adjustment in Examples 1-4, achieved a synergistic effect, resulting in the formation of dense flocs with a three-dimensional network structure within the settling layer. This shortened the settling time to within 4.5 hours, and the solid content of the concentrated slurry was ≥30%, achieving efficient primary enrichment of germanium dioxide. This process innovatively adopts a three-stage countercurrent washing process and a staged heating and drying method, saving more than 45% of water compared with traditional processes. At the same time, it effectively dries and avoids the crystal transformation of germanium dioxide, obtaining crude germanium dioxide solid with a product purity ≥99.5% and a germanium dioxide recovery rate of up to 99.1%. As shown in Table 2, Examples 1-3, compared with Comparative Example 1, indicate that pH adjustment has a significant effect on the germanium and Fe content of the two-stage chelating resin. 2+ / Cu² +The process has a significant impact on the deep removal of metal ions. Adjusting the pH in this process can improve the absorption effect of the chelating resin. In addition, the ultrafiltration membrane with a molecular weight cutoff of 10kDa and SPEEK material has a service life that can be extended by 3 times and the annual maintenance cost reduced by 30% compared with PES resin membrane.

[0085] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A high-efficiency sedimentation and recycling process for germanium dioxide in hydrogen peroxide tail gas absorbent, characterized in that, Includes the following steps: S1: Pass the tail gas absorption liquid in the spray tower into the settling tank and let it stand. Pass the top supernatant into the supernatant overflow tank and the bottom settling layer into the settling zone. S2: After adjusting the pH of the sedimentation layer in the sedimentation inner zone with nitric acid, a composite flocculant is added, stirred, and allowed to stand to obtain germanium dioxide concentrated slurry. The germanium dioxide concentrated slurry is then filtered to obtain filter cake and filtrate, respectively. S3: The filter cake from S2 is subjected to a three-stage countercurrent washing process to remove residual hydrogen peroxide and soluble salts from the filter cake. The washing water is deionized water. S4: The filter cake washed in S3 is dried by staged heating to obtain crude solid germanium dioxide; S5: Combine the supernatant obtained in S1 and the filtrate obtained in S2 into a mixed solution. Adjust the pH of the mixed solution with nitric acid, add hydrogen peroxide as a stabilizer, and then adsorb and remove germanium and Fe from the mixed solution. 2+ / Cu 2+ Metal ions; S6: The liquid obtained after adsorption treatment of the mixture in S5 is subjected to ultrafiltration to remove colloidal germanium and suspended solids other than colloidal germanium. The resulting purified liquid enters the absorption liquid circulation tank. S7: Monitor the concentration of hydrogen peroxide in the absorption liquid circulation tank, add hydrogen peroxide according to the monitored concentration until the concentration of hydrogen peroxide in the circulation tank reaches the set value, and then pass it into the spray tower in the tail gas system for recycling.

2. The efficient sedimentation and recycling process for germanium dioxide in hydrogen peroxide tail gas absorbent as described in claim 1, characterized in that, In S2, the concentration of nitric acid is 5-10%, and the pH of the sedimentation layer is adjusted to 2.0-5.

0.

3. The efficient sedimentation and recycling process for germanium dioxide in hydrogen peroxide tail gas absorbent as described in claim 1, characterized in that, In S2, the composite flocculant is a composite of anionic polyacrylamide and polyaluminum chloride, wherein the dosage of anionic polyacrylamide is 1.0~2.0 ppm and the dosage of polyaluminum chloride is 10~30 ppm. The specific method for stirring and settling is as follows: stir at 100~150 rpm for 30 minutes and let stand at room temperature for 2~5 hours.

4. The efficient sedimentation and recycling process for germanium dioxide in hydrogen peroxide tail gas absorbent as described in claim 1, characterized in that, In S3, during the three-stage countercurrent washing process, the mass ratio of deionized water to filter cake is 3:1 to 5:1, and the temperature of the deionized water is 50 to 80 ℃.

5. The efficient sedimentation and recycling process for germanium dioxide in hydrogen peroxide tail gas absorbent as described in claim 1, characterized in that, In S5, the concentration of nitric acid is 5-10%, and the pH of the mixture is adjusted to 3.0-5.0; the hydrogen peroxide stabilizer is disodium EDTA, and the amount added is 1% of the volume of the mixture.

6. The efficient sedimentation and recycling process for germanium dioxide in hydrogen peroxide tail gas absorbent as described in claim 1, characterized in that, In S5, the adsorption method is as follows: the mixture is passed sequentially through a fixed-bed ion exchange column and a chelating resin column to remove germanium and Fe from the mixture, respectively. 2+ / Cu 2+ Metal ions; the fixed bed ion exchange column uses D403 chelating resin, and the chelating resin column uses Chelex 100.

7. The efficient sedimentation and recycling process for germanium dioxide in hydrogen peroxide tail gas absorbent as described in claim 1, characterized in that, In S4, the staged heating and drying method is as follows: the obtained filter cake is successively heated and dried at 60 ℃, 80 ℃, 100 ℃, and 120 ℃ for 2 hours, 2 hours, 2 hours, and 4 hours respectively.

8. The efficient sedimentation and recycling process for germanium dioxide in hydrogen peroxide tail gas absorbent as described in claim 1, characterized in that, In S6, the ultrafiltration operation to retain colloidal germanium in the liquid is performed by using a sulfonated polyether ether ketone membrane with a molecular weight cutoff of 10 kDa and operating at a pressure of 0.1~0.3 MPa.

9. The efficient sedimentation and recycling process for germanium dioxide in hydrogen peroxide tail gas absorbent as described in claim 1, characterized in that, In S7, the concentration of the added hydrogen peroxide solution is 30%. After adding the hydrogen peroxide solution, the concentration of hydrogen peroxide in the absorption liquid circulation tank reaches 10±0.5% for subsequent recycling.

10. The application of the high-efficiency sedimentation and recycling process of germanium dioxide in hydrogen peroxide tail gas absorbent as described in claim 1 in the purification and resource recovery of germanium-containing tail gas in semiconductor wafer manufacturing, photovoltaic cell material production, optical fiber preform preparation and special gas production processes.

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