Nanometer platinum colloid and its application in determination of hydrogen content in water

Abstract

The present application relates to a kind of nano platinum colloids and its preparation method and its application, the average particle size of the nano platinum colloids is 50-100nm, D90 is 100-150nm, D10 is 30-70nm, zeta potential is-25mV to-40mV, pd I is 0.2-0.5, sphericity is 0.85-0.97.The nano platinum colloids prepared by the present application has small particle size, as catalyst has higher catalytic efficiency, can quickly capture hydrogen to occur reaction, is not influenced by hydrogen escape, is used in the detection reagent for determining the dissolved hydrogen concentration in water, reaction rate is fast, titration result is more accurate.

Description

Technical Field

[0001] This invention relates to the field of environmental protection, and in particular to a nano-platinum colloid and its application in determining the hydrogen content in water. Background Technology

[0002] Hydrogen-rich water is water containing hydrogen gas. In recent years, leveraging the properties and advantages of hydrogen molecules in anti-oxidation, zero residue, and environmental friendliness, hydrogen-rich water has been widely used in agriculture, food, environment, and medical science. Hydrogen concentration is a key parameter in hydrogen-rich water, directly affecting its accessibility and biological intake. Due to the low solubility of hydrogen, with a saturation concentration of only 1.6 mg / L, improving hydrogen solubility is crucial to overcoming this application bottleneck.

[0003] Conventional techniques for measuring hydrogen content in water include gas chromatography and titration using methylene blue (MB)-platinum colloidal reagent (redox method). Gas chromatography is the most accurate method for measuring hydrogen content in gases, with the lowest detection limit and no upper limit, but it requires pretreatment, is time-consuming, cannot provide results immediately, and is costly. Titration is a simple and economical method, but during the measurement process, the escape of hydrogen gas, the presence of ultrafine bubbles in the water, the concentration of methylene blue, and the volume of the titration droplet can all affect the measurement results. Therefore, there is a need to research a titration reagent that provides faster and more accurate detection results and its applications. Summary of the Invention

[0004] The purpose of this invention is to provide a nano-platinum colloid with an average particle size of 50-100 nm, a D90 of 100-150 nm, a D10 of 30-70 nm, a zeta potential of -25 mV to -40 mV, a pdI of 0.2-0.5, and a sphericity of 0.85-0.97.

[0005] In a preferred embodiment of the present invention, the average particle size of the nano-platinum colloid is 60-80 nm, the D90 is 110-130 nm, and the D10 is 50-65 nm.

[0006] In a preferred embodiment of the present invention, the purity of the nano-platinum colloid is 99%, preferably greater than 99.5%, and more preferably greater than 99.95%.

[0007] In a preferred embodiment of the present invention, the zeta potential of the nano-platinum colloid is -30mV to -40mV.

[0008] In a preferred embodiment of the present invention, the pdI of the nano-platinum colloid is 0.3-0.5.

[0009] In a preferred embodiment of the present invention, the sphericity of the nano-platinum colloid is 0.9-0.97.

[0010] The preferred embodiment of the present invention includes the following steps in the preparation method of the nano-platinum colloid:

[0011] (1) Add chloroplatinic acid hydrate to boiling deionized water to prepare a chloroplatinic acid aqueous solution with a concentration of 0.1 g / L-0.25 g / L, and boil for 30-40 min;

[0012] (2) Add a sodium citrate solution with a concentration of 10 g / L-25 g / L to the chloroplatinic acid aqueous solution in step (1) after aerating with nitrogen for 10-15 min. Boil for 1 h-4 h until the solution turns black and no longer darkens. Cool to room temperature to obtain the reaction solution. Pass the reaction solution through an ion exchange resin column and collect the effluent.

[0013] (3) The effluent collected in step (2) and the PVP ethanol solution with a concentration of 3 mg / mL-15 mg / mL are mixed evenly at a volume ratio of 1:1-4 and then freeze-dried to obtain the final product.

[0014] In a preferred embodiment of the present invention, the cooling to room temperature is achieved by cooling to room temperature using an ice bath.

[0015] In a preferred embodiment of the present invention, the freeze-drying conditions are: temperature of -50 to -20°C, vacuum degree of 0 Pa to 25 Pa, and freeze-drying time of 12 h to 48 h.

[0016] In a preferred embodiment of the present invention, the ion exchange resin is selected from any one or a combination of anion exchange resins and cation exchange resins.

[0017] In a preferred embodiment of the present invention, the ion exchange resin is a mixed ion exchange resin obtained by mixing anion exchange resin and cation exchange resin, with a mixing ratio of 1-10:1-10, preferably 56-62:38-44.

[0018] In a preferred embodiment of the present invention, the flow rate of the reaction solution through the ion exchange resin is 1-6 column volumes / h.

[0019] In a preferred embodiment of the present invention, the mixed ion exchange resin is eluted with deionized water at a flow rate of 1-4 column volumes / h.

[0020] In a preferred embodiment of the present invention, there is at least one ion exchange resin column, the working temperature of the ion exchange resin column is 15-50℃, and the height-to-diameter ratio is (3-10):1.

[0021] In a preferred embodiment of the present invention, the cation exchange resin is eluted and regenerated using an acid solution with a concentration of 1-2%, wherein the acid solution is an aqueous solution of any one or a combination of sulfuric acid, phosphoric acid, acetic acid, hydrochloric acid, and nitric acid.

[0022] In a preferred embodiment of the present invention, the elution flow rate of the acid solution is 1-4 column volumes / h.

[0023] In a preferred embodiment of the present invention, the anion exchange resin is eluted and regenerated using an alkaline solution with a concentration of 3-4%, wherein the alkaline solution is an aqueous solution prepared from any one of sodium hydroxide, potassium hydroxide, or a combination thereof.

[0024] In a preferred embodiment of the present invention, the elution flow rate of the alkaline solution is 1-4 column volumes / h.

[0025] Another object of the present invention is to provide a method for preparing nano-platinum colloids, comprising the following steps:

[0026] (1) Add chloroplatinic acid hydrate to boiling deionized water to prepare a chloroplatinic acid aqueous solution with a concentration of 0.1 g / L-0.25 g / L, and boil for 30-40 min;

[0027] (2) Add a sodium citrate solution with a concentration of 10 g / L-25 g / L to the chloroplatinic acid aqueous solution in step (1) after aerating with nitrogen for 10-15 min. Boil for 1 h-4 h until the solution turns black and no longer darkens. Cool to room temperature to obtain the reaction solution. Pass the reaction solution through an ion exchange resin column and collect the effluent.

[0028] (3) The effluent collected in step (2) and the PVP ethanol solution with a concentration of 3 mg / mL-15 mg / mL are mixed evenly at a volume ratio of 1:1-4 and then freeze-dried to obtain the final product.

[0029] In a preferred embodiment of the present invention, the freeze-drying conditions are: temperature of -50 to -20°C, vacuum degree of 0 Pa to 25 Pa, and freeze-drying time of 12 h to 48 h.

[0030] In a preferred embodiment of the present invention, the cooling to room temperature is achieved by cooling to room temperature using an ice bath.

[0031] In a preferred embodiment of the present invention, the ion exchange resin is selected from any one or a combination of anion exchange resins and cation exchange resins.

[0032] In a preferred embodiment of the present invention, the ion exchange resin is a mixed ion exchange resin obtained by mixing anion exchange resin and cation exchange resin, with a mixing ratio of 1-10:1-10, preferably 56-62:38-44.

[0033] In a preferred embodiment of the present invention, the flow rate of the reaction solution through the ion exchange resin is 1-6 column volumes / h.

[0034] In a preferred embodiment of the present invention, the mixed ion exchange resin is eluted with deionized water at a flow rate of 1-4 column volumes / h.

[0035] In a preferred embodiment of the present invention, there is at least one ion exchange resin column, the working temperature of the ion exchange resin column is 15-50℃, and the height-to-diameter ratio is (3-10):1.

[0036] In a preferred embodiment of the present invention, the cation exchange resin is eluted and regenerated using an acid solution with a concentration of 1-2%, wherein the acid solution is an aqueous solution of any one or a combination of sulfuric acid, phosphoric acid, acetic acid, hydrochloric acid, and nitric acid.

[0037] In a preferred embodiment of the present invention, the elution flow rate of the acid solution is 1-4 column volumes / h.

[0038] In a preferred embodiment of the present invention, the anion exchange resin is eluted and regenerated using an alkaline solution with a concentration of 3-4%, wherein the alkaline solution is an aqueous solution prepared from any one of sodium hydroxide, potassium hydroxide, or a combination thereof.

[0039] In a preferred embodiment of the present invention, the elution flow rate of the alkaline solution is 1-4 column volumes / h.

[0040] Another object of the present invention is to provide the application of the nano-platinum colloid of the present invention in a detection reagent for determining the concentration of dissolved hydrogen in water.

[0041] Another object of the present invention is to provide a titration reagent for determining the concentration of dissolved hydrogen in water, comprising a 0.3% methylene blue ethanol solution and a platinum concentration of (1-10)*10. -4 The nano-platinum colloidal dispersion has a volume ratio of g / mL to 1-30:1, preferably 10-20:1.

[0042] In a preferred embodiment of the present invention, the nano-platinum colloidal dispersion is prepared by dissolving the nano-platinum colloid of the present invention in ethanol.

[0043] Another object of the present invention is to provide a nano-platinum colloid detection kit containing the titration reagent of the present invention for determining the concentration of dissolved hydrogen in water.

[0044] Unless otherwise stated, when this invention relates to percentages between liquids, the percentage is volume / volume percentage; when this invention relates to percentages between liquids and solids, the percentage is volume / weight percentage; when this invention relates to percentages between solids and liquids, the percentage is weight / volume percentage; the remainder is weight / weight percentage.

[0045] Unless otherwise stated, this invention utilizes ZetaView dynamic light scattering (Particle Metrix, Germany), Malvern laser particle size analyzer, single particle analyzer, and scanning electron microscope to detect the particle size, Zeta potential, PdI, and scanning electron microscope images of platinum nanoparticle colloids.

[0046] Compared with the prior art, the technical effects of the present invention are as follows:

[0047] 1. The nano-platinum colloid prepared by this invention has a small particle size and high catalytic efficiency as a catalyst. It can quickly capture hydrogen and react without being affected by hydrogen escape. When used in the detection reagent for determining the concentration of dissolved hydrogen in water, the reaction rate is fast and the titration results are more accurate.

[0048] 2. The preparation process of this invention is simple, the production cost is low, and it can be industrialized. Attached Figure Description

[0049] Figure 1 Scanning electron microscope image of the nano-platinum colloid of the present invention. Detailed Implementation

[0050] The following examples further illustrate specific embodiments of the present invention. The reagents and materials used in the examples are as follows:

[0051] Chloroplatinic acid hydrate: chemical formula H2PtCl6·6H2O, commercially purchased from Shanghai Aladdin Biochemical Technology Co., Ltd.

[0052] Sodium citrate solution with a concentration of 10-25 g / L: Add an appropriate amount of sodium citrate to 100 mL of pure water and mix well.

[0053] A 10 mg / mL PVP ethanol solution is prepared by adding 4 g of PVP to 400 mL of ethanol and mixing thoroughly.

[0054] A 5 mg / mL PVP ethanol solution is prepared by adding 2.25 g of PVP to 450 mL of ethanol and mixing thoroughly.

[0055] A 4 mg / mL PVP ethanol solution is prepared by adding 0.8 g PVP to 200 mL of ethanol and mixing thoroughly.

[0056] A 0.3% methylene blue ethanol solution is prepared by dissolving 0.3g of methylene blue in 99.7g of 98% ethanol and mixing thoroughly.

[0057] Mixed ion exchange resin (AmberLite) TMMB), Commercially available: Ion exchange resin obtained by mixing anion exchange resin and cation exchange resin in a mixing ratio of 62-56:38-44.

[0058] All other reagents were purchased commercially.

[0059] Example 1: Preparation of the nano-platinum colloid of the present invention

[0060] (1) Add chloroplatinic acid hydrate to 200 mL of boiled deionized water to obtain a chloroplatinic acid aqueous solution with a concentration of 0.18 g / L, and boil for 30 minutes;

[0061] (2) After aerating 30 mL of sodium citrate solution with a concentration of 25 g / L under nitrogen for 15 minutes, quickly add it to the chloroplatinic acid aqueous solution prepared in step (1), boil for 2 hours, and let the solution turn black until it no longer darkens. Cool to room temperature in an ice-water bath at 0°C to obtain the reaction solution. The reaction solution is then flowed through a mixed ion exchange resin (AmberLite) at a flow rate of 5 column volumes / h. TM The ion exchange resin column of MB is used to collect the effluent;

[0062] (3) Take 10 mL of the effluent collected in step (2) and 20 mL of a 10 mg / mL PVP ethanol solution, mix them thoroughly, and freeze-dry at -20℃ and 0 Pa for 12 h to obtain platinum nanoparticles. The average particle size of the platinum nanoparticles was 74 nm, D90 was 118 nm, D10 was 58 nm, zeta potential was -40 mV, pdI was 0.49, sphericity was 0.94, and purity was 99%. Scanning electron microscopy images are shown below. Figure 1 .

[0063] Example 2: Preparation of the nano-platinum colloid of the present invention

[0064] (1) Add chloroplatinic acid hydrate to 200 mL of boiled deionized water to obtain a chloroplatinic acid aqueous solution with a concentration of 0.15 g / L, and boil for 30 minutes;

[0065] (2) After aerating 25 mL of sodium citrate solution with a concentration of 20 g / L with nitrogen for 10 minutes, quickly add it to the chloroplatinic acid aqueous solution prepared in step (1), boil for 1.5 h, and continue boiling until the solution turns black and no longer darkens. Cool to room temperature in an ice-water bath at 0 °C to obtain the reaction solution. Flow the reaction solution through a mixed ion exchange resin (AmberLite) at a flow rate of 6 column volumes / h. TM The ion exchange resin column of MB is used to collect the effluent;

[0066] (3) Take 20 mL of the effluent collected in step (2) and 30 mL of a 5 mg / mL PVP ethanol solution, mix them thoroughly, and freeze-dry them at -20℃ and 0 Pa for 24 h to obtain nano-platinum colloids. The nano-platinum colloids were tested and found to have an average particle size of 68 nm, a D90 of 120 nm, a D10 of 52 nm, a zeta potential of -34 mV, a pdI of 0.44, a sphericity of 0.96, and a purity of 99.5%.

[0067] Example 3: Preparation of the nano-platinum colloid of the present invention

[0068] (1) Add chloroplatinic acid hydrate to 200 mL of boiling deionized water to obtain a chloroplatinic acid aqueous solution with a concentration of 0.12 g / L, and boil for 30 minutes;

[0069] (2) After aerating 15 mL of sodium citrate solution with a concentration of 15 g / L with nitrogen for 10 minutes, quickly add it to the chloroplatinic acid aqueous solution prepared in step (1), boil for 1.5 h, and continue boiling until the solution turns black and no longer darkens. Cool to room temperature in an ice-water bath at 0 °C to obtain the reaction solution. Flow the reaction solution through a mixed ion exchange resin (AmberLite) at a flow rate of 5 column volumes / h. TM The ion exchange resin column of MB is used to collect the effluent;

[0070] (3) Take 30 mL of the effluent collected in step (2) and 40 mL of PVP ethanol solution with a concentration of 4 mg / mL, mix them evenly, and freeze-dry them at -20℃ and 0 Pa for 20 h to obtain nano-platinum colloids. The nano-platinum colloids were tested and found to have an average particle size of 79 nm, a D90 of 115 nm, a D10 of 61 nm, a zeta potential of -37 mV, a pdI of 0.39, a sphericity of 0.91, and a purity of 99%.

[0071] Example 4: Preparation of the titration reagent for determining the concentration of dissolved hydrogen in water according to the present invention

[0072] The nano-platinum colloid from Example 1 was dissolved in 5 mL of ethanol to obtain a platinum concentration of 3*10. -4 To obtain the titration reagent, take 0.2 mL of a g / mL platinum nanocolloid dispersion and add it to 2 mL of a 0.3% methylene blue ethanol solution. Mix well.

[0073] Example 5: Preparation of the titration reagent for determining the concentration of dissolved hydrogen in water according to the present invention.

[0074] The nano-platinum colloid from Example 2 was dissolved in 5 mL of ethanol to obtain a platinum concentration of 5*10. -4To obtain the titration reagent, take 0.2 mL of a g / mL platinum nanocolloid dispersion and add it to 3 mL of a 0.3% methylene blue ethanol solution. Mix well.

[0075] Example 6: Preparation of the titration reagent for determining the concentration of dissolved hydrogen in water according to the present invention

[0076] The nano-platinum colloid from Example 3 was dissolved in 5 mL of ethanol to obtain a platinum concentration of 10 × 10⁻⁶. -4 To obtain the titration reagent, take 0.2 mL of a g / mL platinum nanocolloid dispersion and add it to 2.5 mL of a 3% methylene blue ethanol solution. Mix well.

[0077] Comparative Example 1

[0078] Commercially available nano-platinum colloid 1 (purchased from Guangzhou Hongwu Materials Technology Co., Ltd., with an average particle size of 20 nm) was dissolved in 5 mL of ethanol to obtain a platinum concentration of 5*10. -4 To obtain the titration reagent, take 0.2 mL of a g / mL platinum nanocolloid dispersion and add it to 2 mL of a 0.3% methylene blue ethanol solution. Mix well.

[0079] Comparative Example 2

[0080] Commercially available nano-platinum colloid 2 (purchased from Beijing Zhongke Keyou Technology Co., Ltd., with an average particle size of 3 nm) was dissolved in 5 mL of ethanol to obtain a platinum concentration of 5*10. -4 To obtain the titration reagent, take 0.2 mL of a g / mL platinum nanocolloid dispersion and add it to 2 mL of a 0.3% methylene blue ethanol solution. Mix well.

[0081] Comparative Example 3

[0082] Commercially available nano-platinum colloid 3 (purchased from Jiangsu Xianfeng Nanomaterials Technology Co., Ltd., with an average particle size of 5 nm) was dissolved in 5 mL of ethanol to obtain a platinum concentration of 5*10. -4 To obtain the titration reagent, take 0.2 mL of a g / mL platinum nanocolloid dispersion and add it to 2 mL of a 0.3% methylene blue ethanol solution. Mix well.

[0083] Experimental Example 1

[0084] Test solutions: Hydrogen-rich water with ultrafine bubbles was prepared by placing water into a nanobubble hydrogen water machine (Shanghai Nanobaber Nanotechnology Co., Ltd.). This water was used for the following group tests. Three test solutions were taken for each group, and each test solution was divided into two equal portions for parallel testing. The sample numbers were 1-1, 1-2, 2-1, 2-2, 3-1, and 3-2. The volume of the dropper was 20 μL.

[0085] Experimental Group 1: Take 6 mL of the test solution and add the titration reagent from Example 4 until the test solution changes from colorless to blue.

[0086] Experimental Group 2: Take 6 mL of the test solution and detect it by gas chromatography. First, put hydrogen ultrafine bubble water in a sealed container, freeze it at -20℃ for 12 h, thaw it at room temperature, and then detect it with a Shimadzu gas chromatograph.

[0087] Control group 1: Take 10 mL of the test solution and add commercially available titration reagent 1 (purchased from Foshan Mailu Environmental Protection Equipment Co., Ltd.) until the test solution changes from colorless to blue.

[0088] Control group 2: Take 6 mL of the test solution and add commercially available titration reagent 2 (purchased from Zhongke Hydrogen Technology (Foshan) Co., Ltd.) until the test solution changes from colorless to blue.

[0089] Control group 3: Take 6 mL of the test solution and add commercially available titration reagent 3 (purchased from Guangdong Jeudao Electrolysis Technology Co., Ltd.) until the test solution changes from colorless to blue.

[0090] Control group 4: Take 6 mL of the test solution and add the titration reagent of Comparative Example 1. The results show that the solution turns blue after the first drop is added, and the blue color does not disappear after shaking, indicating that the titration reagent has no effect.

[0091] Control group 5: Take 6 mL of the test solution and add the titration reagent of Comparative Example 2. The results show that the solution turns blue after the first drop is added, and the blue color does not disappear after shaking, indicating that the titration reagent has no effect.

[0092] Control group 6: Take 6 mL of the test solution and add the titration reagent of Comparative Example 3. The results show that the solution turns blue after the first drop is added, and the blue color does not disappear after shaking, indicating that the titration reagent has no effect.

[0093] The test results are shown in Table 1. The experimental errors of test groups 1 and 2 are within the range of 0.02-0.2 mg / L, which can be used as an alternative method to gas chromatography.

[0094] The above description of specific embodiments of the present invention does not limit the present invention. Those skilled in the art can make various changes or modifications based on the present invention, and as long as they do not depart from the spirit of the present invention, they should all fall within the scope of protection of the claims of the present invention.

[0095] Table 1

[0096]

Claims

1. A titrant for determining the concentration of dissolved hydrogen in water, comprising a 0.3% methylene blue ethanol solution and a platinum concentration of (1-10)*10 -4 The composition is a platinum nanoparticle colloidal dispersion with a volume ratio of g / mL, wherein the two components are 10-20:

1. The platinum nanoparticle colloidal dispersion is prepared by dissolving platinum nanoparticles in ethanol. The platinum nanoparticles have an average particle size of 50-100 nm, a D90 of 100-150 nm, a D10 of 30-70 nm, a zeta potential of -25 mV to -40 mV, a PDI of 0.2-0.5, and a sphericity of 0.85-0.

97. The purity of the platinum nanoparticles is 99%. The preparation method of the platinum nanoparticles includes the following steps: (1) Add chloroplatinic acid hydrate to boiling deionized water to prepare a chloroplatinic acid aqueous solution with a concentration of 0.1 g / L-0.25 g / L, and boil for 30-40 min; (2) Add a sodium citrate solution with a concentration of 10 g / L-25 g / L to the chloroplatinic acid aqueous solution in step (1) after aerating it with nitrogen for 10-15 min. Boil for 1 h-4 h until the solution turns black and no longer darkens. Cool to room temperature to obtain the reaction solution. Pass the reaction solution through an ion exchange resin column and collect the effluent. (3) The effluent collected in step (2) and a PVP ethanol solution with a concentration of 3 mg / mL-15 mg / mL are mixed evenly at a volume ratio of 1:1-4 and then freeze-dried to obtain the final product.

2. The titration reagent according to claim 1, wherein the average particle size of the platinum nanoparticle colloid is 60-80 nm, D90 is 110-130 nm, and D10 is 50-65 nm.

3. The titration reagent as described in claim 1, wherein the purity of the nano-platinum colloid is greater than 99.5%.

4. The titration reagent as described in claim 3, wherein the purity of the nano-platinum colloid is greater than 99.95%.

5. The titration reagent according to claim 1, wherein the zeta potential of the platinum nanoparticle colloid is -30mV to -40mV.

6. The titration reagent as described in claim 1, wherein the PDI of the nanoplatinum colloid is 0.3-0.

5.

7. The titration reagent according to claim 1, wherein the sphericity of the platinum nanoparticle colloid is 0.9-0.

97.

8. The titration reagent according to any one of claims 1-7, wherein the freeze-drying conditions are: temperature of -50 to -20°C, vacuum degree of 0 Pa to 25 Pa, and freeze-drying time of 12 h to 48 h.

9. The titration reagent according to any one of claims 1-7, wherein the ion exchange resin is selected from any one or a combination of anion exchange resins, cation exchange resins.

10. The titration reagent according to any one of claims 1-7, wherein the ion exchange resin is a mixed ion exchange resin obtained by mixing anion exchange resin and cation exchange resin, and the mixing ratio is 1-10:1-10.

11. The titration reagent according to any one of claims 1-7, wherein the ion exchange resin is a mixed ion exchange resin obtained by mixing anion exchange resin and cation exchange resin, and the mixing ratio is 56-62:38-44.

12. The titration reagent according to any one of claims 1-7, wherein the flow rate of the reaction solution through the ion exchange resin is 1-6 column volumes / h.

13. The titration reagent as described in claim 10, wherein the mixed ion exchange resin is eluted with deionized water at a flow rate of 1-4 column volumes / h.

14. The titration reagent according to any one of claims 1-7, wherein there is at least one ion exchange resin column, the working temperature of the ion exchange resin column is 15-50℃, and the height-to-diameter ratio is (3-10):

1.

15. The titration reagent according to claim 9, wherein the cation exchange resin is eluted and regenerated with an acid solution of 1-2% concentration, the acid solution being an aqueous solution of any one or a combination of sulfuric acid, phosphoric acid, acetic acid, hydrochloric acid, and nitric acid.

16. The titration reagent as described in claim 15, wherein the elution flow rate of the acid solution is 1-4 column volumes / h.

17. The titration reagent as described in claim 9, wherein the anion exchange resin is eluted and regenerated with an alkaline solution of concentration 3-4%, the alkaline solution being an aqueous solution of an alkaline solution prepared from any one or a combination of sodium hydroxide and potassium hydroxide.

18. The titration reagent as described in claim 17, wherein the elution flow rate of the alkaline solution is 1-4 column volumes / h.

19. A nano-platinum colloid detection kit, comprising a titration reagent for determining the concentration of dissolved hydrogen in water as described in any one of claims 1-18.

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