Total arsenic online monitoring reagent formula and preparation method

Abstract

The invention discloses a total arsenic online monitoring reagent formula and a preparation method, the total arsenic online monitoring reagent formula comprises a reagent A, a reagent B, a reagent C, a reagent D and a total arsenic standard solution, the reagent A is composed of sulfuric acid, potassium persulfate and pure water, the reagent B is composed of sodium acetate trihydrate, glacial acetic acid, an emulsifier OP-10, silver carbonate, absolute ethyl alcohol and pure water, the reagent C is composed of sulfuric acid, tartaric acid and pure water, and the reagent D is composed of sodium acetate trihydrate, glacial acetic acid, an emulsifier OP-10, silver carbonate, absolute ethyl alcohol and pure water. The reagent D is composed of potassium hydroxide, potassium borohydride and pure water, and the total arsenic standard solution is mother liquor with the concentration of 1000 mg / L. Through the synergistic effect of silver carbonate in the reagent B and the emulsifier OP-10, interference substances such as sulfides and heavy metal ions can be effectively shielded, the relative standard deviation of a monitoring result is smaller than or equal to 5%, and the accuracy of monitoring data is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of water quality detection, and in particular to a total arsenic online monitoring reagent formula and configuration method. Background Art

[0002] Arsenic is a highly toxic heavy metal. Long-term ingestion of arsenic-containing water can cause skin cancer, lung cancer, and nervous system damage, posing a serious threat to public health. Therefore, achieving high-sensitivity and high-stability online monitoring of total arsenic in water is a key step in environmental protection.

[0003] In the field of water quality monitoring, online monitoring of total arsenic is crucial for environmental protection and public health. As a highly toxic substance, long-term ingestion of arsenic can lead to serious diseases such as skin lesions and cancer. Existing total arsenic monitoring reagents have the following problems:

[0004] The reagents are easily affected by factors such as ambient temperature and light, which can cause fluctuations in redox efficiency and reduce the accuracy of monitoring data.

[0005] Therefore, we proposed a total arsenic online monitoring reagent formula and configuration method. Summary of the Invention

[0006] The purpose of the present invention is to provide a total arsenic online monitoring reagent formula and configuration method, which solves the problems raised in the background technology.

[0007] To achieve the above object, the present invention provides the following technical solution: a total arsenic online monitoring reagent formula, comprising reagent A, reagent B, reagent C, reagent D and a total arsenic standard solution, wherein:

[0008] Reagent A is composed of sulfuric acid, potassium persulfate and pure water, the volume fraction of sulfuric acid is 0.8%-1.2%, and the mass fraction of potassium persulfate is 0.8%-1.2%;

[0009] Reagent B is composed of sodium acetate trihydrate, glacial acetic acid, emulsifier OP-10, silver carbonate, anhydrous ethanol and pure water, the mass fraction of sodium acetate trihydrate is 4%-5%, the volume fraction of glacial acetic acid is 0.2%-0.3%, the volume fraction of emulsifier OP-10 is 0.15%-0.25%, the mass fraction of silver carbonate is 0.015%-0.025%, and the volume fraction of anhydrous ethanol is 2%-3%;

[0010] Reagent C is composed of sulfuric acid, tartaric acid and pure water, with the volume fraction of sulfuric acid being 1.1%-1.3% and the mass fraction of tartaric acid being 7%-9%;

[0011] Reagent D is composed of potassium hydroxide, potassium borohydride and pure water, the mass fraction of potassium hydroxide is 0.5%-0.6%, and the mass fraction of potassium borohydride is 3%-4%;

[0012] The total arsenic standard solution is a stock solution with a concentration of 1000 mg / L, which should be diluted according to the test requirements when used.

[0013] As a preferred embodiment of the present invention, reagent A is composed of sulfuric acid, potassium persulfate and pure water, the volume fraction of sulfuric acid is 1%, and the mass fraction of potassium persulfate is 1%;

[0014] Reagent B is composed of sodium acetate trihydrate, glacial acetic acid, emulsifier OP-10, silver carbonate, anhydrous ethanol and pure water, with the mass fraction of sodium acetate trihydrate being 4.5%, the volume fraction of glacial acetic acid being 0.2%, the volume fraction of emulsifier OP-10 being 0.2%, the mass fraction of silver carbonate being 0.015%, and the volume fraction of anhydrous ethanol being 2.5%;

[0015] Reagent C consists of sulfuric acid, tartaric acid and pure water, with the volume fraction of sulfuric acid being 1.2% and the mass fraction of tartaric acid being 8%;

[0016] Reagent D consists of potassium hydroxide, potassium borohydride and pure water, the mass fraction of potassium hydroxide is 0.5%, and the mass fraction of potassium borohydride is 3%.

[0017] As a preferred embodiment of the present invention, reagent A is composed of sulfuric acid, potassium persulfate and pure water, the volume fraction of sulfuric acid is 0.9%, and the mass fraction of potassium persulfate is 0.9%;

[0018] Reagent B is composed of sodium acetate trihydrate, glacial acetic acid, emulsifier OP-10, silver carbonate, anhydrous ethanol and pure water, the mass fraction of sodium acetate trihydrate is 4.25%, the volume fraction of glacial acetic acid is 0.175%, the volume fraction of emulsifier OP-10 is 0.175%, the mass fraction of silver carbonate is 0.0125%, and the volume fraction of anhydrous ethanol is 3%;

[0019] Reagent C is composed of sulfuric acid, tartaric acid and pure water, with the volume fraction of sulfuric acid being 1.1% and the mass fraction of tartaric acid being 7.5%;

[0020] Reagent D consists of potassium hydroxide, potassium borohydride and pure water, the mass fraction of potassium hydroxide is 0.45%, and the mass fraction of potassium borohydride is 2.75%.

[0021] As a preferred embodiment of the present invention, reagent A is composed of sulfuric acid, potassium persulfate and pure water, the volume fraction of sulfuric acid is 1.1%, and the mass fraction of potassium persulfate is 1.1%;

[0022] Reagent B is composed of sodium acetate trihydrate, glacial acetic acid, emulsifier OP-10, silver carbonate, anhydrous ethanol and pure water, the mass fraction of sodium acetate trihydrate is 4.75%, the volume fraction of glacial acetic acid is 0.225%, the volume fraction of emulsifier OP-10 is 0.225%, the mass fraction of silver carbonate is 0.0175%, and the volume fraction of anhydrous ethanol is 2%;

[0023] Reagent C is composed of sulfuric acid, tartaric acid and pure water, with the volume fraction of sulfuric acid being 1.3% and the mass fraction of tartaric acid being 8.5%;

[0024] Reagent D consists of potassium hydroxide, potassium borohydride and pure water, the mass fraction of potassium hydroxide is 0.5%, and the mass fraction of potassium borohydride is 3.25%.

[0025] As a preferred embodiment of the present invention, the sulfuric acid in reagent A is analytical grade, and the potassium persulfate is premium grade; the sodium acetate trihydrate, glacial acetic acid, and anhydrous ethanol in reagent B are analytical grade, the emulsifier OP-10 is chemically pure, and the silver carbonate is a high-purity reagent; the sulfuric acid in reagent C is analytical grade, and the tartaric acid is premium grade; and the potassium hydroxide and potassium borohydride in reagent D are analytical grade.

[0026] As a preferred embodiment of the present invention, the reagents A, C, and D are stored in polyethylene bottles at a storage temperature of 8-12°C and a shelf life of 25-35 days; the reagent B is stored in a chlorine-free polyethylene bottle at a storage temperature of 8-12°C and a shelf life of 10-20 days; and the total arsenic standard solution is stored in a glass bottle at room temperature and a shelf life of 25-35 days.

[0027] The present invention also relates to a method for preparing a total arsenic online monitoring reagent formula, comprising the following steps:

[0028] Preparation of Reagent A: Add an appropriate amount of pure water to a beaker, slowly add sulfuric acid while stirring, cool to room temperature, add potassium persulfate, stir until completely dissolved, transfer to a volumetric flask, dilute to volume with pure water, shake well, and transfer to a polyethylene bottle for storage;

[0029] Preparation of Reagent B: First, treat the preparation vessel to be chlorine-free. Add pure water to a beaker, then add sodium acetate trihydrate and glacial acetic acid, stirring to dissolve. In another small beaker, dissolve emulsifier OP-10 in anhydrous ethanol and pour into the above beaker. After diluting to volume, add silver carbonate, stirring to dissolve, and transfer to a polyethylene bottle for storage.

[0030] Reagent C preparation: Add pure water to a beaker, add sulfuric acid while stirring, cool, add tartaric acid, stir to dissolve, transfer to a volumetric flask, shake well, and transfer to a polyethylene bottle for storage;

[0031] Reagent D preparation: Add pure water to a beaker, add potassium hydroxide and stir to dissolve, cool, add potassium borohydride, stir to dissolve, and transfer to a polyethylene bottle for storage;

[0032] Preparation of total arsenic standard solution: Pretreat volumetric flasks, pipettes and other instruments, soak them in a specific solution, then rinse them. Pipette different volumes of 1000 mg / L arsenic standard solution into the corresponding volumetric flask and adjust the volume to obtain standard intermediate solutions of different concentrations. Then dilute them as needed to obtain the calibration solution and store it in a glass bottle.

[0033] Furthermore, during the preparation of reagents A, C, and D, sulfuric acid should be added slowly and with constant stirring to prevent local overheating; when preparing reagent B, silver carbonate should be added after the solution has been diluted to volume and when the temperature is relatively low to avoid decomposition; when preparing the total arsenic standard solution, the solution used for pre-treating the dishes is 50%-60% nitric acid, and the soaking time is 20-24 hours.

[0034] Compared with the prior art, the present invention has the following beneficial effects:

[0035] The present invention can effectively shield interfering substances such as sulfide and heavy metal ions through the synergistic effect of silver carbonate in reagent B and emulsifier OP-10, making the relative standard deviation of the monitoring results ≤5%, which is conducive to improving the accuracy of monitoring data;

[0036] The optimized ratio of concentrated sulfuric acid and potassium persulfate in Reagent A ensures the thoroughness of the oxidation reaction and avoids the efficiency fluctuation caused by high-temperature decomposition of traditional reagents;

[0037] The reagent is valid for up to 1 month when refrigerated at 10°C, and the validity period of reagent B is 15 days, which is 50% longer than that of traditional reagents, reducing the workload of frequent liquid preparation. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Other features, objects and advantages of the present invention will become more apparent upon reading the detailed description of non-limiting embodiments with reference to the following drawings:

[0039] Figure 1 The present invention is a flow chart of a method for configuring a total arsenic online monitoring reagent formula. DETAILED DESCRIPTION

[0040] In order to make the technical means, creative features, objectives and effects achieved by the present invention easier to understand, the present invention is further described below in conjunction with specific implementation methods.

[0041] Example 1

[0042] Reagent formula

[0043] Reagent A:

[0044] Composition: Take 10 mL of analytical grade sulfuric acid (AR) and 10 g of premium grade potassium persulfate (GR) and add them to 980 mL of pure water. The volume fraction of sulfuric acid is about 1%, and the mass fraction of potassium persulfate is about 1%.

[0045] Storage: Transfer to a polyethylene bottle and store in a refrigerator at 10°C. The shelf life is 30 days.

[0046] Reagent B:

[0047] Composition: In a 2000mL beaker that has been treated to be free of chlorine, add 1800mL of pure water, followed by 90g of analytically pure sodium acetate trihydrate and 4mL of analytically pure glacial acetic acid, and stir to dissolve. In a 100mL small beaker, dissolve 3mL of chemically pure emulsifier OP-10 in 40mL of pure water, then slowly pour the mixture into the large beaker. Finally, add 0.3g of high-purity reagent silver carbonate, stir until completely dissolved, and dilute to 2000mL with pure water. At this point, the mass fraction of sodium acetate trihydrate is 4.5%, the volume fraction of glacial acetic acid is 0.2%, the volume fraction of emulsifier OP-10 is 0.2%, the mass fraction of silver carbonate is 0.015%, and the volume fraction of anhydrous ethanol is 2.5%.

[0048] Storage: Transfer to a chlorine-free polyethylene bottle and refrigerate at 10°C. The shelf life is 15 days.

[0049] Reagent C:

[0050] Composition: Take 12 mL of analytical grade sulfuric acid (AR) and 80 g of premium grade tartaric acid (GR) and add them to 988 mL of pure water. The volume fraction of sulfuric acid is about 1.2% and the mass fraction of tartaric acid is about 8%.

[0051] Storage: Transfer to a polyethylene bottle and store in a refrigerator at 10°C. The shelf life is 30 days.

[0052] Reagent D:

[0053] Composition: Take 10g of analytically pure potassium hydroxide (AR) and 60g of analytically pure potassium borohydride (AR) and add them to 1930mL of pure water. The mass fraction of potassium hydroxide is about 0.5% and the mass fraction of potassium borohydride is about 3%.

[0054] Storage: Transfer to a polyethylene bottle and store in a refrigerator at 10°C. The shelf life is 30 days.

[0055] Total arsenic standard solution

[0056] Composition: Use a stock solution with a concentration of 1000 mg / L.

[0057] Storage: Store in a glass bottle at room temperature. The shelf life is 30 days.

[0058] The configuration method is as follows:

[0059] Reagent A configuration

[0060] Add 400 mL of pure water to a 1000 mL beaker and slowly add 10 mL of concentrated sulfuric acid while stirring. After cooling to room temperature, add 10 g of potassium persulfate and stir until completely dissolved. Transfer the solution to a 1000 mL volumetric flask. Rinse the beaker and glass rod three times with pure water, add the washings to the volumetric flask, dilute to the mark, shake well, transfer to a polyethylene bottle, and refrigerate at 10°C.

[0061] Reagent B configuration

[0062] Soak the preparation container in 55% nitric acid for 22 hours, rinse with clean water, and then rinse three times with pure water. Add 1800 mL of pure water to a 2000 mL beaker, followed by 90 g of sodium acetate trihydrate and 4 mL of glacial acetic acid, stirring to dissolve. Dissolve 3 mL of emulsifier OP-10 in 40 mL of pure water in a 100 mL beaker, then pour the mixture into the beaker. Make the volume up to 2000 mL with pure water, then add 0.3 g of silver carbonate, stirring to dissolve. Transfer the mixture to a chlorine-free polyethylene bottle and refrigerate at 10°C.

[0063] Reagent C configuration

[0064] Add 400 mL of pure water to a 1000 mL beaker. While stirring, add 12 mL of concentrated sulfuric acid. After cooling, add 80 g of tartaric acid and stir until dissolved. Transfer the solution to a 1000 mL volumetric flask. Rinse the container three times, adding the washings to the volumetric flask. Dose to volume, shake well, transfer to a polyethylene bottle, and refrigerate at 10°C.

[0065] Reagent D configuration

[0066] Add 1930 mL of pure water to a 2000 mL beaker, add 10 g of potassium hydroxide and stir until dissolved. After cooling, add 60 g of potassium borohydride and continue stirring until completely dissolved. Transfer to a polyethylene bottle and refrigerate at 10°C.

[0067] Total arsenic standard solution preparation

[0068] Soak volumetric flasks, pipettes, and other instruments in 55% nitric acid for 22 hours, rinse with clean water, and then rinse three times with pure water. Pipette 80 mL of the 1 mg / L standard solution into a 500 mL volumetric flask, add 0.25 mL of concentrated sulfuric acid, and dilute to volume with pure water to obtain the standard solution (0.16 mg / L). Store in a glass bottle until ready for use.

[0069] Detection:

[0070] The prepared reagents were matched with the automated sampling system to detect the total arsenic content in a certain industrial wastewater sample. Reagent B was consumed 16mL each time, and the standard solution was diluted 10 times. The obtained standard curve had a linear relationship R2 =0.9992. The test results showed that the total arsenic content in the water sample was 0.25 mg / L.

[0071] Example 2

[0072] Reagent A

[0073] Composition: Take 9 mL of analytical grade sulfuric acid (AR) and 9 g of premium grade potassium persulfate (GR), add them to 982 mL of pure water, the volume fraction of sulfuric acid is about 0.9%, and the mass fraction of potassium persulfate is about 0.9%.

[0074] Storage: Transfer to a polyethylene bottle and store in a refrigerator at 8°C. The shelf life is 25 days.

[0075] Reagent B

[0076] Composition: In a 2000mL beaker that has been treated with chlorine-free water, add 1850mL of pure water, then add 85g of analytically pure sodium acetate trihydrate (AR) and 3.5mL of analytically pure glacial acetic acid (AR) in sequence, and stir to dissolve. In a 100mL small beaker, dissolve 2.5mL of chemically pure emulsifier OP-10 (CP) with 35mL of pure water, and then slowly pour it into the above large beaker. Finally, add 0.25g of high-purity reagent silver carbonate (HP), stir until completely dissolved, and dilute to 2000mL with pure water. At this time, the mass fraction of sodium acetate trihydrate is 4.25%, the volume fraction of glacial acetic acid is 0.175%, the volume fraction of emulsifier OP-10 is 0.175%, the mass fraction of silver carbonate is 0.0125%, and the volume fraction of anhydrous ethanol is 3%.

[0077] Storage: Transfer to a chlorine-free polyethylene bottle and refrigerate at 8°C. The shelf life is 10 days.

[0078] Reagent C

[0079] Composition: Add 11 mL of analytical grade sulfuric acid (AR) and 75 g of premium grade tartaric acid (GR) to 989 mL of pure water. The volume fraction of sulfuric acid is approximately 1.1% and the mass fraction of tartaric acid is approximately 7.5%.

[0080] Storage: Transfer to a polyethylene bottle and store in a refrigerator at 8°C. The shelf life is 25 days.

[0081] Reagent D

[0082] Composition: Take 9g of analytically pure potassium hydroxide (AR) and 55g of analytically pure potassium borohydride (AR) and add them to 1936mL of pure water. At this time, the mass fraction of potassium hydroxide is about 0.45%, and the mass fraction of potassium borohydride is about 2.75%.

[0083] Storage: Transfer to a polyethylene bottle and store in a refrigerator at 8°C. The shelf life is 25 days.

[0084] Total arsenic standard solution

[0085] Composition: Use a stock solution with a concentration of 1000 mg / L.

[0086] Storage: Store in a glass bottle at room temperature. The shelf life is 25 days.

[0087] Configuration Method

[0088] Reagent A configuration

[0089] Add 400 mL of pure water to a 1000 mL beaker and slowly add 9 mL of concentrated sulfuric acid while stirring. After cooling to room temperature, add 9 g of potassium persulfate and stir until completely dissolved. Transfer the solution to a 1000 mL volumetric flask. Rinse the beaker and glass rod three times with pure water, add the washings to the volumetric flask, and dilute to the mark. Shake well, transfer to a polyethylene bottle, and refrigerate at 8°C.

[0090] Reagent B configuration

[0091] Soak the preparation container in 50% nitric acid for 20 hours, rinse with clean water, and then rinse three times with pure water. Add 1850 mL of pure water to a 2000 mL beaker, followed by 85 g of sodium acetate trihydrate and 3.5 mL of glacial acetic acid, stirring to dissolve. Dissolve 2.5 mL of emulsifier OP-10 in 35 mL of pure water in a 100 mL beaker, then pour the mixture into the beaker. Make the volume up to 2000 mL with pure water, then add 0.25 g of silver carbonate, stirring to dissolve. Transfer the mixture to a chlorine-free polyethylene bottle and refrigerate at 8°C.

[0092] Reagent C configuration

[0093] Add 400 mL of pure water to a 1000 mL beaker. While stirring, add 11 mL of concentrated sulfuric acid. After cooling, add 75 g of tartaric acid and stir until dissolved. Transfer the solution to a 1000 mL volumetric flask. Rinse the container three times, adding the washings to the volumetric flask. Dose to volume, shake well, transfer to a polyethylene bottle, and refrigerate at 8°C.

[0094] Reagent D configuration

[0095] Add 1936 mL of pure water to a 2000 mL beaker, add 9 g of potassium hydroxide and stir until dissolved. After cooling, add 55 g of potassium borohydride and continue stirring until completely dissolved. Transfer to a polyethylene bottle and refrigerate at 8°C.

[0096] Total arsenic standard solution preparation

[0097] Soak volumetric flasks, pipettes, and other instruments in 50% nitric acid for 20 hours, rinse with clean water, and then rinse three times with pure water. Pipette 70 mL of the 1 mg / L standard solution into a 500 mL volumetric flask, add 0.2 mL of concentrated sulfuric acid, and dilute to volume with pure water to obtain the standard solution (0.14 mg / L). Store in a glass bottle until ready for use.

[0098] Detection:

[0099] The prepared reagent was used to detect the total arsenic content in a groundwater sample. Reagent B was consumed 15mL each time, and the standard solution was diluted 8 times. The obtained standard curve had a linear relationship R 2 =0.9985. The test results showed that the total arsenic content in the water sample was 0.005 mg / L.

[0100] Example 3

[0101] Reagent formula

[0102] Composition: Take 11 mL of analytical grade sulfuric acid (AR) and 11 g of premium grade potassium persulfate (GR) and add them to 978 mL of pure water. The volume fraction of sulfuric acid is approximately 1.1%, and the mass fraction of potassium persulfate is approximately 1.1%.

[0103] Storage: Transfer to a polyethylene bottle and store in a refrigerator at 12°C. The shelf life is 35 days.

[0104] Reagent B

[0105] Composition: In a 2000mL beaker that has been treated to be free of chlorine, add 1750mL of pure water, followed by 95g of analytically pure sodium acetate trihydrate (AR) and 4.5mL of analytically pure glacial acetic acid (AR), and stir to dissolve. In a 100mL small beaker, dissolve 3.5mL of chemically pure emulsifier OP-10 (CP) in 45mL of pure water, then slowly pour the mixture into the large beaker. Finally, add 0.35g of high-purity reagent silver carbonate (HP), stir until completely dissolved, and dilute to 2000mL with pure water. At this point, the mass fraction of sodium acetate trihydrate is 4.75%, the volume fraction of glacial acetic acid is 0.225%, the volume fraction of emulsifier OP-10 is 0.225%, the mass fraction of silver carbonate is 0.0175%, and the volume fraction of anhydrous ethanol is 2%.

[0106] Storage: Transfer to a chlorine-free polyethylene bottle and refrigerate at 12°C. The shelf life is 20 days.

[0107] Reagent C

[0108] Composition: Add 13 mL of analytical grade sulfuric acid (AR) and 85 g of premium grade tartaric acid (GR) to 987 mL of pure water. The volume fraction of sulfuric acid is approximately 1.3% and the mass fraction of tartaric acid is approximately 8.5%.

[0109] Storage: Transfer to a polyethylene bottle and store in a refrigerator at 12°C. The shelf life is 35 days.

[0110] Reagent D

[0111] Composition: Take 11g of analytically pure potassium hydroxide (AR) and 65g of analytically pure potassium borohydride (AR) and add them to 1924mL of pure water. The mass fraction of potassium hydroxide is about 0.55% and the mass fraction of potassium borohydride is about 3.25%.

[0112] Storage: Transfer to a polyethylene bottle and store in a refrigerator at 12°C. The shelf life is 35 days.

[0113] Total arsenic standard solution

[0114] Composition: Use a stock solution with a concentration of 1000 mg / L.

[0115] Storage: Store in a glass bottle at room temperature. The shelf life is 35 days.

[0116] Configuration Method

[0117] Reagent A configuration

[0118] Add 400 mL of pure water to a 1000 mL beaker and slowly add 11 mL of concentrated sulfuric acid while stirring. After cooling to room temperature, add 11 g of potassium persulfate and stir until completely dissolved. Transfer the solution to a 1000 mL volumetric flask. Rinse the beaker and glass rod three times with pure water, add the washings to the volumetric flask, bring the volume to the mark, shake well, transfer to a polyethylene bottle, and refrigerate at 12°C.

[0119] Reagent B configuration

[0120] Soak the preparation container in 60% nitric acid for 24 hours, rinse with clean water, and then rinse three times with pure water. Add 1750 mL of pure water to a 2000 mL beaker, followed by 95 g of sodium acetate trihydrate and 4.5 mL of glacial acetic acid, stirring to dissolve. Dissolve 3.5 mL of emulsifier OP-10 in 45 mL of pure water in a 100 mL beaker, then pour the mixture into the beaker. Make the volume up to 2000 mL with pure water, then add 0.35 g of silver carbonate, stirring to dissolve. Transfer the mixture to a chlorine-free polyethylene bottle and refrigerate at 12°C.

[0121] Reagent C configuration

[0122] Add 400 mL of pure water to a 1000 mL beaker. While stirring, add 13 mL of concentrated sulfuric acid. After cooling, add 85 g of tartaric acid and stir until dissolved. Transfer the solution to a 1000 mL volumetric flask. Rinse the container three times, adding the washings to the volumetric flask. Dose to volume, shake well, transfer to a polyethylene bottle, and refrigerate at 12°C.

[0123] Reagent D configuration

[0124] Add 1924 mL of pure water to a 2000 mL beaker, add 11 g of potassium hydroxide and stir until dissolved. After cooling, add 65 g of potassium borohydride and continue stirring until completely dissolved. Transfer to a polyethylene bottle and refrigerate at 12°C.

[0125] Total arsenic standard solution preparation

[0126] Soak volumetric flasks, pipettes, and other instruments in 60% nitric acid for 24 hours, rinse with clean water, and then rinse three times with pure water. Pipette 90 mL of the 1 mg / L standard solution into a 500 mL volumetric flask, add 0.3 mL of concentrated sulfuric acid, and dilute to volume with pure water to obtain the standard solution (0.18 mg / L). Store in a glass bottle until ready for use.

[0127] Detection:

[0128] The prepared reagent was used to detect the total arsenic content in a surface water sample. Reagent B was consumed 17 mL each time, and the standard solution was diluted 12 times. The obtained standard curve had a linear relationship R 2 =0.999, the test results show that the total arsenic content in the water sample is 0.05 mg / L.

[0129] Comparative Example

[0130] Reagent A

[0131] Composition: Take 5 mL of analytical grade sulfuric acid (AR) and 5 g of ordinary grade potassium persulfate (high purity grades such as premium grade are not specified) and add them to 990 mL of pure water. The volume fraction of sulfuric acid is about 0.5%, and the mass fraction of potassium persulfate is about 0.5%.

[0132] Storage: Transfer to an ordinary glass bottle and store at room temperature. The expiration date is not specified.

[0133] Reagent B

[0134] Composition: In an ordinary 2000mL beaker that has not been specially treated, add 1950mL of pure water, and then add 70g of analytically pure sodium acetate trihydrate and 2mL of analytically pure glacial acetic acid, and stir to dissolve. In a 100mL small beaker, dissolve 1mL of ordinary emulsifier (chemical purity and other specifications are not specified) with 20mL of pure water, and then pour it into the above-mentioned large beaker. Finally, add 0.1g of ordinary silver carbonate (high-purity reagent grade is not specified), stir until dissolved, and make up to 2000mL with pure water. At this time, the mass fraction of sodium acetate trihydrate is 3.5%, the volume fraction of glacial acetic acid is 0.1%, the volume fraction of emulsifier is 0.05%, and the mass fraction of silver carbonate is 0.005%. There is no mention of anhydrous ethanol.

[0135] Storage: Transfer to ordinary polyethylene bottle and store at room temperature. The expiration date is not specified.

[0136] Reagent C

[0137] Composition: Add 8 mL of analytical grade sulfuric acid (AR) and 60 g of standard purity tartaric acid (high purity grades such as premium grade are not specified) to 992 mL of pure water. The sulfuric acid volume fraction is approximately 0.8% and the tartaric acid mass fraction is approximately 6%.

[0138] Storage: Transfer to an ordinary glass bottle and store at room temperature. The expiration date is not specified.

[0139] Reagent D

[0140] Composition: Take 6g of analytically pure potassium hydroxide (AR) and 40g of analytically pure potassium borohydride (AR) and add them to 1954mL of pure water. The mass fraction of potassium hydroxide is about 0.3% and the mass fraction of potassium borohydride is about 2%.

[0141] Storage: Transfer to ordinary polyethylene bottle and store at room temperature. The expiration date is not specified.

[0142] Total arsenic standard solution

[0143] Composition: Use a stock solution with a concentration of 1000 mg / L.

[0144] Storage: Store in ordinary glass bottles at room temperature. The expiration date is not specified.

[0145] Reagent A configuration

[0146] Add 300 mL of pure water to a 1000 mL beaker. While stirring, add 5 mL of concentrated sulfuric acid. Without cooling to room temperature, add 5 g of potassium persulfate and stir until dissolved. Transfer the solution to a 1000 mL volumetric flask. Rinse the beaker and glass rod 1-2 times with pure water. Add the washings to the volumetric flask, dilute to the mark, shake well, transfer to a standard glass bottle, and store at room temperature.

[0147] Reagent B configuration

[0148] Simply rinse the preparation container with clean water. Add 1950 mL of pure water to a 2000 mL beaker, followed by 70 g of sodium acetate trihydrate and 2 mL of glacial acetic acid, stirring to dissolve. Dissolve 1 mL of emulsifier in 20 mL of pure water in a 100 mL beaker, then pour the mixture into the beaker. Make the volume up to 2000 mL with pure water, then add 0.1 g of silver carbonate, stirring to dissolve. Transfer the mixture to a standard polyethylene bottle and store at room temperature.

[0149] Reagent C configuration

[0150] Add 300 mL of pure water to a 1000 mL beaker. While stirring, add 8 mL of concentrated sulfuric acid. Add 60 g of tartaric acid while still cool and stir until dissolved. Transfer the solution to a 1000 mL volumetric flask. Rinse the container 1-2 times, add the washings to the volumetric flask, bring to volume, shake well, transfer to a standard glass bottle, and store at room temperature.

[0151] Reagent D configuration

[0152] Add 1954 mL of pure water to a 2000 mL beaker, add 6 g of potassium hydroxide and stir until dissolved. Without cooling, add 40 g of potassium borohydride and continue stirring until dissolved. Transfer to an ordinary polyethylene bottle and place at room temperature.

[0153] Total arsenic standard solution preparation

[0154] Rinse the volumetric flask, pipette, and other instruments with only clean water. Pipette 50 mL of the 1 mg / L standard solution into a 500 mL volumetric flask, add 0.1 mL of concentrated sulfuric acid, and dilute to volume with pure water to obtain the standard solution (0.1 mg / L). Store in a regular glass bottle until ready for use.

[0155] Detection

[0156] The prepared reagent was used to detect the total arsenic content in an unknown water sample. Reagent B was consumed 13 mL each time, and the standard solution was diluted 6 times. The obtained standard curve had a linear relationship R 2 =0.995, and the test results showed that the total arsenic content in the water sample was 0.002 mg / L.

[0157] The above three embodiments and comparative examples were tested, and the test results are shown in the following table:

[0158]

[0159] The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention. It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention. Therefore, the embodiments should be regarded as illustrative and non-restrictive in all respects. The scope of the present invention is defined by the appended claims rather than the foregoing description, and all changes that come within the meaning and range of equivalents of the claims are intended to be included therein.

[0160] In addition, it should be understood that although this specification is described in terms of implementation methods, not every implementation method contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

Claims

1. A total arsenic online monitoring reagent formula, characterized by: Includes reagent A, reagent B, reagent C, reagent D and total arsenic standard solution, of which: Reagent A is composed of sulfuric acid, potassium persulfate and pure water, the volume fraction of sulfuric acid is 0.8%-1.2%, and the mass fraction of potassium persulfate is 0.8%-1.2%; Reagent B is composed of sodium acetate trihydrate, glacial acetic acid, emulsifier OP-10, silver carbonate, anhydrous ethanol and pure water, the mass fraction of sodium acetate trihydrate is 4%-5%, the volume fraction of glacial acetic acid is 0.2%-0.3%, the volume fraction of emulsifier OP-10 is 0.15%-0.25%, the mass fraction of silver carbonate is 0.015%-0.025%, and the volume fraction of anhydrous ethanol is 2%-3%; Reagent C is composed of sulfuric acid, tartaric acid and pure water, with the volume fraction of sulfuric acid being 1.1%-1.3% and the mass fraction of tartaric acid being 7%-9%; Reagent D is composed of potassium hydroxide, potassium borohydride and pure water, the mass fraction of potassium hydroxide is 0.5%-0.6%, and the mass fraction of potassium borohydride is 3%-4%; The total arsenic standard solution is a stock solution with a concentration of 1000 mg / L, which should be diluted according to the test requirements when used.

2. A total arsenic online monitoring reagent formula according to claim 1, characterized in that: Reagent A consists of sulfuric acid, potassium persulfate and pure water, with the volume fraction of sulfuric acid being 1% and the mass fraction of potassium persulfate being 1%; Reagent B is composed of sodium acetate trihydrate, glacial acetic acid, emulsifier OP-10, silver carbonate, anhydrous ethanol and pure water, with the mass fraction of sodium acetate trihydrate being 4.5%, the volume fraction of glacial acetic acid being 0.2%, the volume fraction of emulsifier OP-10 being 0.2%, the mass fraction of silver carbonate being 0.015%, and the volume fraction of anhydrous ethanol being 2.5%; Reagent C consists of sulfuric acid, tartaric acid and pure water, with the volume fraction of sulfuric acid being 1.2% and the mass fraction of tartaric acid being 8%; Reagent D consists of potassium hydroxide, potassium borohydride and pure water, the mass fraction of potassium hydroxide is 0.5%, and the mass fraction of potassium borohydride is 3%.

3. A total arsenic online monitoring reagent formula according to claim 1, characterized in that: Reagent A consists of sulfuric acid, potassium persulfate and pure water, with the volume fraction of sulfuric acid being 0.9% and the mass fraction of potassium persulfate being 0.9%; Reagent B is composed of sodium acetate trihydrate, glacial acetic acid, emulsifier OP-10, silver carbonate, anhydrous ethanol and pure water, the mass fraction of sodium acetate trihydrate is 4.25%, the volume fraction of glacial acetic acid is 0.175%, the volume fraction of emulsifier OP-10 is 0.175%, the mass fraction of silver carbonate is 0.0125%, and the volume fraction of anhydrous ethanol is 3%; Reagent C is composed of sulfuric acid, tartaric acid and pure water, with the volume fraction of sulfuric acid being 1.1% and the mass fraction of tartaric acid being 7.5%; Reagent D consists of potassium hydroxide, potassium borohydride and pure water, the mass fraction of potassium hydroxide is 0.45%, and the mass fraction of potassium borohydride is 2.75%.

4. The total arsenic online monitoring reagent formulation and configuration method according to claim 1, characterized in that: Reagent A consists of sulfuric acid, potassium persulfate and pure water, with the volume fraction of sulfuric acid being 1.1% and the mass fraction of potassium persulfate being 1.1%; Reagent B is composed of sodium acetate trihydrate, glacial acetic acid, emulsifier OP-10, silver carbonate, anhydrous ethanol and pure water, the mass fraction of sodium acetate trihydrate is 4.75%, the volume fraction of glacial acetic acid is 0.225%, the volume fraction of emulsifier OP-10 is 0.225%, the mass fraction of silver carbonate is 0.0175%, and the volume fraction of anhydrous ethanol is 2%; Reagent C is composed of sulfuric acid, tartaric acid and pure water, with the volume fraction of sulfuric acid being 1.3% and the mass fraction of tartaric acid being 8.5%; Reagent D consists of potassium hydroxide, potassium borohydride and pure water, the mass fraction of potassium hydroxide is 0.5%, and the mass fraction of potassium borohydride is 3.25%.

5. A total arsenic online monitoring reagent formula according to claim 1, characterized in that: The sulfuric acid in reagent A is analytical grade, and the potassium persulfate is premium grade; the sodium acetate trihydrate, glacial acetic acid, and anhydrous ethanol in reagent B are analytical grade, the emulsifier OP-10 is chemical grade, and the silver carbonate is a high-purity reagent; the sulfuric acid in reagent C is analytical grade, and the tartaric acid is premium grade; the potassium hydroxide and potassium borohydride in reagent D are analytical grade.

6. A total arsenic online monitoring reagent formulation according to claim 1, characterized in that: The reagents A, C, and D are stored in polyethylene bottles at a storage temperature of 8-12° C. and have a shelf life of 25-35 days. The reagent B is stored in a chlorine-free polyethylene bottle at a storage temperature of 8-12° C. and has a shelf life of 10-20 days. The total arsenic standard solution is stored in a glass bottle at room temperature and has a shelf life of 25-35 days.

7. A method for preparing a total arsenic online monitoring reagent formula, applicable to the total arsenic online monitoring reagent formula according to any one of claims 1 to 6, characterized in that: The following steps are involved: Preparation of Reagent A: Add an appropriate amount of pure water to a beaker, slowly add sulfuric acid while stirring, cool to room temperature, add potassium persulfate, stir until completely dissolved, transfer to a volumetric flask, dilute to volume with pure water, shake well, and transfer to a polyethylene bottle for storage; Preparation of Reagent B: First, treat the preparation vessel to be chlorine-free. Add pure water to a beaker, then add sodium acetate trihydrate and glacial acetic acid, stirring to dissolve. In another small beaker, dissolve emulsifier OP-10 in anhydrous ethanol and pour into the above beaker. After diluting to volume, add silver carbonate, stirring to dissolve, and transfer to a polyethylene bottle for storage. Reagent C preparation: Add pure water to a beaker, add sulfuric acid while stirring, cool, add tartaric acid, stir to dissolve, transfer to a volumetric flask, shake well, and transfer to a polyethylene bottle for storage; Reagent D preparation: Add pure water to a beaker, add potassium hydroxide and stir to dissolve, cool, add potassium borohydride, stir to dissolve, and transfer to a polyethylene bottle for storage; Preparation of total arsenic standard solution: Pretreat volumetric flasks, pipettes and other instruments, soak them in a specific solution, then rinse them. Pipette different volumes of 1000 mg / L arsenic standard solution into the corresponding volumetric flask and adjust the volume to obtain standard intermediate solutions of different concentrations. Then dilute them as needed to obtain the calibration solution and store it in a glass bottle.

8. The method for preparing a total arsenic online monitoring reagent formula according to claim 7, characterized in that: During the preparation of Reagents A, C, and D, sulfuric acid should be added slowly and with constant stirring to prevent local overheating. When preparing Reagent B, silver carbonate should be added after the solution has been diluted to volume and when the temperature is relatively low to avoid decomposition. When preparing the total arsenic standard solution, the solution used for pre-treating the dishes is 50%-60% nitric acid, and the soaking time is 20-24 hours.

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