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HJ 585-2010: Water quality. Determination of free chlorine and total chlorine. Titrimetric method using N, N-diethyl-1, 4-phenylenediamine
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Water quality. Determination of free chlorine and total chlorine. Titrimetric method using N, N-diethyl-1, 4-phenylenediamine
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HJ 585-2010
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Basic data | Standard ID | HJ 585-2010 (HJ585-2010) | | Description (Translated English) | Water quality. Determination of free chlorine and total chlorine. Titrimetric method using N, N-diethyl-1, 4-phenylenediamine | | Sector / Industry | Environmental Protection Industry Standard | | Classification of Chinese Standard | Z16 | | Classification of International Standard | 13.060.01 | | Word Count Estimation | 13,128 | | Date of Issue | 2010-09-20 | | Date of Implementation | 2010-12-01 | | Older Standard (superseded by this standard) | GB 11897-1989 | | Quoted Standard | GB/T 5750.10; GB/T 5750.11 | | Regulation (derived from) | Department of Environmental Protection Notice No. 68 of 2010 | | Issuing agency(ies) | Ministry of Ecology and Environment | | Summary | This standard specifies the determination of free chlorine and total chlorine titration. This standard applies to industrial waste, medical waste, sewage, water and sewage water for regeneration of the landscape of free chlorine and total chlorine. | HJ 585-2010: Water quality. Determination of free chlorine and total chlorine. Titrimetric method using N, N-diethyl-1, 4-phenylenediamine
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Water quality.Determination of free chlorine and total chlorine.Titrimetric method using N, N-diethyl-1, 4-phenylenediamine
National Environmental Protection Standard of the People's Republic
Replace GB 11897-89
Determination of free chlorine and total chlorine in water
N,N-diethyl-1,4-phenylenediamine titration
Water quality-Determination of free chlorine and total chlorine-
Titrimetric method using N,N-diethyl-1,4-phenylenediamine
Released on.2010-09-20
2010-12-01 Implementation
Ministry of Environmental Protection released
Ministry of Environmental Protection
announcement
No. 68 of.2010
In order to implement the "Environmental Protection Law of the People's Republic of China", protect the environment, and protect human health, we now approve the "environmental air benzene series"
Five standards, such as solid adsorption/thermal desorption-gas chromatography, are considered as national environmental protection standards and are released.
The standard name and number are as follows.
I. Determination of Benzene in Ambient Air Solid Adsorption/Thermal Desorption-Gas Chromatography (HJ 583-2010);
2. Determination of Benzene in Ambient Air Activated Carbon Adsorption/Carbon Disulfide Desorption - Gas Chromatography (HJ 584-2010);
4. Determination of free chlorine and total chlorine in water - N,N-diethyl-1,4-phenylenediamine spectrophotometric method (HJ 586-2010);
V. "Determination of water quality atrazine by high performance liquid chromatography" (HJ 587-2010).
The above standards have been implemented since December 1,.2010 and published by the China Environmental Science Press. The standard content can be found on the website of the Ministry of Environmental Protection.
From the date of implementation of the above standards, the following four national environmental protection standards approved and issued by the former National Environmental Protection Agency shall be abolished.
The name and number are as follows.
I. Determination of Air Quality, Toluene, Xylene and Styrene by Gas Chromatography (GB/T 14677-93);
2. Determination of Air Quality Styrene by Gas Chromatography (GB/T 14670-93);
3. Determination of free chlorine and total chlorine in water. N,N-diethyl-1,4-phenylenediamine titration method (GB 11897-89);
4. Determination of free chlorine and total chlorine in water quality N,N-Diethyl-1,4-phenylenediamine spectrophotometric method (GB 11898-89).
Special announcement.
September 20,.2010
Content
Foreword..iv
1 Scope..1
2 Normative references..1
3 Terms and Definitions.1
4 principle of the method..2
5 interference and elimination. 2
6 reagents and materials. 2
7 instruments and equipment.4
8 samples.4
9 Analysis steps..4
10 Results calculation and representation 5
11 Precision and Accuracy 5
12 Notes 6
Appendix A (normative appendix) Determination of three forms of combined chlorine in monochloramine, dichloramine and nitrogen trichloride..7
Iv
Foreword
To protect the environment and protect the human body in order to implement the Environmental Protection Law of the People's Republic of China and the Law of the People's Republic of China on Water Pollution Prevention and Control
This standard is developed for the determination of free chlorine and total chlorine in water.
This standard specifies the determination of free chlorine and total chlorine in landscape water for industrial wastewater, medical wastewater, domestic sewage, intermediate water and sewage regeneration.
N,N-Diethyl-1,4-phenylenediamine titration.
This standard is for the determination of free chlorine and total chlorine in water, N, N-diethyl-1,4-phenylenediamine titration (GB 11897-89)
Revised.
This standard was first published in 1989. The original standard was drafted. Anhui Environmental Monitoring Center, China Academy of Preventive Medicine Environmental Health
Health Monitoring Institute and Anhui Wuhu Environmental Monitoring Center Station. This is the first revision. The main contents of the revision are as follows.
-- Revised the scope of application of the standard;
- Increased method of preservation of samples;
- increased interference and elimination clauses;
-- Modified the amount of buffer solution added;
-- Added considerations.
From the date of implementation of this standard, the national environmental protection standard “Water” approved and issued by the former National Environmental Protection Agency on December 25, 1989
Determination of free chlorine and total chlorine The N,N-diethyl-1,4-phenylenediamine titration method (GB 11897-89) was abolished.
Appendix A of this standard is a normative appendix.
This standard was formulated by the Science and Technology Standards Department of the Ministry of Environmental Protection.
This standard is mainly drafted by. Dalian Environmental Monitoring Center.
This standard is verified by. Liaoning Provincial Environmental Monitoring Experimental Center, Anshan Environmental Monitoring Center, Yingkou Environmental Monitoring Center, Shenyang City
Environmental Monitoring Center, Jinzhou Environmental Monitoring Center.
This standard was approved by the Ministry of Environmental Protection on September 20,.2010.
This standard has been implemented since December 1,.2010.
This standard is explained by the Ministry of Environmental Protection.
Determination of free chlorine and total chlorine in water
N,N-diethyl-1,4-phenylenediamine titration
Warning. Mercury salt is a highly toxic chemical. Wear protective equipment as required to avoid contact with skin and clothing. Waste after inspection
The liquid should be properly and safely handled.
1 Scope of application
This standard specifies the titration method for the determination of free chlorine and total chlorine in water.
This standard applies to the measurement of free chlorine and total chlorine in landscape water for industrial wastewater, medical wastewater, domestic sewage, intermediate water and sewage regeneration.
set.
The detection limit (in terms of Cl2) of this standard is 0.02 mg/L, and the measurement range (in terms of Cl2) is 0.08 to 5.00 mg/L. For free chlorine
The sample having a total chlorine concentration exceeding the upper limit of the method can be appropriately diluted and then measured.
2 Normative references
The contents of this standard refer to the terms in the following documents. For undated references, the valid version applies to this standard.
GB/T 5750.10 Standard Test Method for Drinking Water Standards for disinfection by-products
GB/T 5750.11 Standard Test Method for Drinking Water Standards
3 Terms and definitions
The following terms and definitions apply to this standard.
3.1
Free chlorine free chlorine
Refers to chlorine in the form of hypochlorous acid, hypochlorite ions and dissolved elemental chlorine.
3.2
Chlorine combined chlorine
Refers to chlorine in the form of chloramines and organic chloramines.
3.3
Total chlorine total chlorine
Refers to chlorine in the form of "free chlorine" or "chlorinated chlorine", or both.
3.4
Chloramine chloramines
A derivative in which one, two or three hydrogen atoms of ammonia are replaced by chlorine atoms as determined by the method (eg monochloramine, dichloramine, nitrogen trichloride)
And chlorinated derivatives of organic nitrogen compounds.
The composition of free chlorine and total chlorine is shown in Table 1.
Table 1 Nouns and their composition
Noun composition
Free chlorine (free residual chlorine)
Active free chlorine elemental chlorine, hypochlorous acid
Potential free chlorine hypochlorite
Total chlorine (total residual chlorine) elemental chlorine, hypochlorous acid, hypochlorite, chloramine
4 Principle of the method
4.1 Determination of free chlorine
At pH 6.2-6.5, free chlorine and N,N-diethyl-1,4-phenylenediamine (DPD) form a red compound with ferrous sulfate
The ammonium standard solution was titrated until the red color disappeared.
4.2 Determination of total chlorine
At pH 6.2-6.5, elemental chlorine, hypochlorous acid, hypochlorite and chloramine react with DPD in the presence of excess potassium iodide.
The red compound was titrated to a red color with a standard solution of ammonium ferrous sulfate.
5 interference and elimination
5.1 Interference from other chlorine compounds
Chlorine dioxide interferes with the determination of free chlorine and total chlorine, and chlorite interferes with the determination of total chlorine. Chlorine dioxide and chlorite
It can be corrected by measuring its concentration. For the determination method, see GB/T 5750.11 and GB/T 5750.10.
High concentrations of monochloramine interfere with the determination of free chlorine. Can be added by adding sodium arsenite solution (6.13) or thioacetamide solution
(6.13) Elimination of interference with monochloramine, determination of monochloramine in accordance with Appendix A.
5.2 Correction of interference between manganese oxide and hexavalent chromium
Manganese oxide and hexavalent chromium can interfere with the determination. The interference can be eliminated by measuring the concentration of manganese oxide and hexavalent chromium.
9.2.
5.3 Interference of other oxides
This method interferes in the presence of the following oxidizing agents. bromine, iodine, bromoamine, iodine, ozone, hydrogen peroxide, chromate, oxidation
Manganese, hexavalent chromium, nitrite, copper ions (Cu2) and iron ions (Fe3). Among them Cu2 (< 8 mg/L) and Fe3 (< 20 mg/L)
The interference can be masked by Na2-EDTA in the buffer solution and DPD solution. The interference of manganese oxide and hexavalent chromium can be determined by titration.
Correction, other oxide interference with sodium arsenite solution (6.13) or thioacetamide solution (6.13) elimination. Chromate interference can pass
Add ruthenium chloride to eliminate.
6 reagents and materials
Unless otherwise stated, analytically pure reagents that meet national standards were used for the analysis.
6.1 Experimental water. It is deionized water or double distilled water containing no chlorine and reducing substances. The experimental water needs to pass the inspection before it can be used.
Test method. Add 100 ml of water to be tested and 1.0 g of potassium iodide (6.4) to the first 250 ml Erlenmeyer flask and mix. After 1 min,
Add 5.0 ml buffer solution (6.11) and 5.0 ml DPD test solution (6.12); then add 100 ml to the second 250 ml Erlenmeyer flask to be tested.
Water and 2 drops of sodium hypochlorite solution (6.6). After 2 min, 5.0 ml buffer solution (6.11) and 5.0 ml DPD test solution (6.12) were added.
The first bottle should not be colored, and the second bottle should be pink. Otherwise, the experimental water should be dechlorinated by activated carbon treatment and pressed.
The steps are checked for quality and can be used until qualified.
6.2 Concentrated sulfuric acid. ρ = 1.84 g/ml.
6.3 orthophosphoric acid. ρ = 1.71 g/ml.
6.4 Potassium iodide. crystal.
6.5 sodium hydroxide solution. c (NaOH) = 2.0 mol/L
Weigh 80.0 g of sodium hydroxide and dissolve in 500 ml of water (6.1). After the solution is cooled, transfer it to a 1 000 ml volumetric flask and add water (6.1).
Go to the marking line and mix.
6.6 sodium hypochlorite solution. ρ(Cl2)≈0.1 g/L
It is diluted by a concentrated solution of sodium hypochlorite (trade name, Antifumin).
6.7 Potassium dichromate standard solution. c (1/6K2Cr2O7) = 100.0 mmol/L
Accurately weigh 4.904 g of finely divided potassium dichromate (baked at 105 ° C for more than 2 h), dissolved in a 1 000 ml volumetric flask, and added water (6.1)
Go to the marking line and mix.
6.8 Ammonium ferrous sulfate stock solution. c[(NH4)2Fe(SO4)2·6H2O]≈56 mmol/L
Weigh 22.0 g of ferrous ammonium hexahydrate, dissolved in water (6.1) containing 5.0 ml of concentrated sulfuric acid (6.2), and transferred to 1 000 ml of brown.
In the volumetric flask, add water (6.1) to the mark and mix. Calibration is performed before measurement.
Calibration method. Add 50.0 ml of ferrous ammonium sulfate stock solution (6.8) and 5.0 ml of orthophosphoric acid (6.3) to a 250 ml Erlenmeyer flask.
And 4 drops of diphenylamine sulfonate indicator solution (6.10). Titrate with potassium dichromate standard solution (6.7) until dark green, the color of the solution remains unchanged
Time is the end point. The concentration of this solution is expressed in millimoles of chlorine (Cl2) per liter, and is calculated according to the formula (1).
twenty two
c Vc
(1)
Where. c1-- ferrous sulfate ammonium stock solution concentration, mmol/L;
C2--concentration of potassium dichromate standard solution, mmol/L;
V2--the volume of the potassium dichromate standard solution consumed by titration, ml;
V1--the volume of ferrous ammonium sulfate stock solution, ml;
2--Ethylene ferrous ammonium sulfate corresponds to the number of moles of chlorine (Cl2).
Note. If V2 is less than 22 ml, the ammonium ferrous sulfate stock solution should be reconstituted.
6.9 Ammonium ferrous sulfate standard titration solution. c[(NH4)2Fe(SO4)2·6H2O]≈2.8 mmol/L
Take 50.0 ml of ferrous ammonium sulfate stock solution (6.8) in a 1 000 ml volumetric flask, add water (6.1) to the mark, mix and store in brown
In the reagent bottle. Available now.
The concentration c3 (mmol/L) of this solution is expressed in millimoles of chlorine (Cl2) per liter, and is calculated according to the formula (2).
Cc = (2)
6.10 Diphenylamine sulfonate indicator solution. ρ[(C6H5-NH-C6H4-SO3)2Ba]=3.0 g/L
Weigh 0.30 g of diphenylamine sulfonate dissolved in a 100 ml volumetric flask, add water (6.1) to the mark, and mix.
6.11 Phosphate buffer solution. pH=6.5
Weigh 24.0 g of anhydrous sodium hydrogen phosphate (Na2HPO4) or 60.5 g of disodium hydrogen phosphate dodecahydrate (Na2HPO4·12H2O), and
46.0 g potassium dihydrogen phosphate (KH2PO4), dissolved in water, and added 100 ml of 8.0 g/L disodium EDTA dihydrate
(C10H14N2O8Na2·2H2O) solution or 0.8 g EDTA disodium solid, transfer to a 1 000 ml volumetric flask, add water (6.1) to the mark,
Mix well. If necessary, 0.020 g of mercuric chloride can be added to prevent mold propagation and interference with traces of iodide in the reagents to the free chlorine test.
6.12 N,N-diethyl-1,4-phenylenediamine sulfate (DPD) solution. ρ[NH2-C6H4-N(C2H5)2·H2SO4]=1.1 g/L
2.0 ml of concentrated sulfuric acid (6.2) and 25 ml of 8.0 g/L dihydrate EDTA disodium solution or 0.2 g EDTA disodium solid,
Add 250 ml of water (6.1) to prepare a mixed solution. Add 1.1 g of anhydrous DPD sulfate or 1.5 g of pentahydrate to the above mixture
In solution, transfer to a 1 000 ml brown volumetric flask, add water (6.1) to the mark and mix. The solution was placed in a brown reagent bottle and stored at 4 °C.
If the solution changes color after standing for a long time, it should be reconstituted.
Note. DPD sulphate can also be replaced by 1.1 g DPD oxalate or 1.0 g DPD hydrochloride.
6.13 sodium arsenite solution, ρ (NaAsO2) = 2.0 g/L; or thioacetamide solution, ρ (CH3CSNH2) = 2.5 g/L.
7 Instruments and equipment
7.1 Microburette. 5 ml, 0.02 ml index.
7.2 Common instruments and equipment used in general laboratories.
Note. The glassware in the experiment should be soaked in sodium hypochlorite solution (6.6) for 1 h, then rinsed thoroughly with water (6.1).
8 samples
8.1 Sample Collection
Free chlorine and total chlorine are unstable and samples should be determined on site as much as possible. If the sample cannot be measured on site, the sample should be stored with a fixative.
Pre-add the sample volume 1% NaOH solution (6.5) to the brown glass bottle, collect the water sample to fill the sample bottle, and immediately cover the plug.
And sealed to avoid contact with air. If the sample is acidic, increase the amount of NaOH solution added to ensure that the pH of the water sample is >12.
8.2 Sample storage
The water samples were transported in a freezer, stored in a laboratory at 4 ° C, protected from light, and measured within 5 days.
9 Analysis steps
9.1 Preparation of samples
Take 100 ml of the sample as sample V0. If the total chlorine (Cl2) exceeds 5 mg/L, take a smaller volume and dilute with water (6.1).
100 ml.
9.2 Determination of free chlorine
In a 250 ml Erlenmeyer flask, add 15.0 ml of phosphate buffer solution (6.11), 5.0 ml of DPD solution (6.12) and sample (9.1).
Mix well. Immediately titrate to the colorless end with ammonium ferrous sulfate standard titration solution (6.9), and record the number of milliliters of the titration solution solution volume V3.
For samples containing manganese oxide and hexavalent chromium, the interference can be eliminated by measuring the content of both. Take 100 ml of sample in a 250 ml Erlenmeyer
Add 1.0 ml of sodium arsenite solution (6.13) or thioacetamide solution (6.13) and mix. Add 15.0 ml phosphate buffer
(6.11) and 5.0 ml DPD solution (6.12), immediately titrated with ammonium ferrous sulfate standard titration solution (6.9), the solution is titrated from pink to none
The color is the end point and the interference of manganese oxide is measured. If hexavalent chromium is present, after 30 minutes, the color of the solution turns pink and continues to titrate hexavalent chromium.
The interference caused the solution to be titrated from pink to colorless as the end point. Record titration consumption solution volume V5, equivalent to dry manganese oxide and hexavalent chromium
Disturb. If the water sample needs to be diluted, the manganese oxide and hexavalent chromium interference of the diluted sample should be determined.
9.3 Determination of total chlorine
In a 250 ml Erlenmeyer flask, add 15.0 ml phosphate buffer solution (6.11), 5.0 ml DPD solution (6.12) and sample.
(9.1), add 1 g of potassium iodide (6.4) and mix. After 2 min, titrate with ammonium ferrous sulfate standard titration solution (6.9) until colorless.
If a pink reproduction is observed within 2 min, the titration is continued until colorless as the end point, and the number of milliliters of the titration solution solution volume V4 is recorded.
For samples containing manganese oxide and hexavalent chromium, the interference can be eliminated by measuring the content. For the determination method, see 9.2.
10 Calculation and representation of results
10.1 Calculation of free chlorine
The mass concentration ρ (calculated as Cl2) of free chlorine in the water sample is calculated according to the formula (3).
( )
(Cl ) = 70.91
c VV
ρ − × (3)
Where. c3-- ammonium ferrous sulfate standard titration concentration (in terms of Cl2), mmol/L;
V3--measurement (9.2) volume of the standard titration solution of ammonium ferrous sulfate, ml;
V5--correction of the volume of ammonium ferrous sulfate standard titration solution when interfering with manganese oxide and hexavalent chromium, ml, if manganese oxide and six are not present
Chromium, V5=0 ml;
V0--sample volume, ml;
The relative molecular mass of 70.91--Cl2.
10.2 Calculation of total chlorine
The mass concentration ρ of the total chlorine in the water sample (calculated as Cl2) is calculated according to the formula (4).
( )
(Cl ) 70.91
c VV=
ρ − × (4)
Where. V4--measurement (9.3) volume of the standard titration solution of ammonium ferrous sulfate, ml.
10.3 Results are expressed
When the measurement result is less than 10 mg/L, it is retained to two decimal places; when it is greater than or equal to 10 mg/L, three significant figures are retained.
11 Precision and accuracy
11.1 Precision
Five laboratories tested uniform samples containing potassium iodate at concentrations of 1.006, 5.03, and 9.05 mg/L.
The relative standard deviations in the experimental room were. 7.6% to 9.6%, 1.0% to 3.8%, and 0.7% to 1.4%;
The relative standard deviations between laboratories were. 1.2%, 1.1%, 0.4%;
The repeatability limits were. 0.25 mg/L, 0.33 mg/L, 0.26 mg/L;
The reproducibility limits were 0.25 mg/L, 0.36 mg/L, and 0.27 mg/L, respectively.
11.2 Accuracy
Five laboratories used sodium hypochlorite to determine the three actual samples from tap water, medical wastewater and domestic sewage.
The spiked recovery rates were. 100% to 103%, 100% to 103%, and 98.1% to 106%;
The final recoveries of the spiked recovery were. 102% ± 2.2%, 99.0% ± 6.2%, and 102% ± 6.4%.
12 Precautions
12.1 When the sample is measured in the field, if the sample is too acidic, too alkaline or the salt concentration is high, increase the amount of phosphate buffer solution added to confirm
The pH of the test sample is between 6.2 and 6.5. When measuring, the sample should avoid glare, shaking and warming.
12.2 If the sample needs to be transported back to the laboratory for analysis, for a very acidic sample, the amount of fixative NaOH solution should be increased to make the sample
pH >12; if the sample NaOH solution is added in a volume greater than 1% of the sample volume, the sample volume V0 should be corrected;
For samples (pH >12), no fixative is required. The amount of phosphate buffer solution should be increased during the measurement to make the pH of the sample at 6.2.
Between 6.5; for the high-salt sample added with fixative, the amount of phosphate buffer solution should also be adjusted to make the pH value of the sample.
Between 6.2 and 6.5.
12.3 Glassware for the determination of free and total chlorine should be used separately to prevent cross-contamination.
Appendix A
(normative appendix)
Determination of three forms of combined chlorine in monochloramine, dichloramine and nitrogen trichloride
A.1 Scope of application
This appendix provides a method for distinguishing between three forms of chlorination of monochloramine, dichloramine and nitrogen trichloride. The method is applicable to free chlorine and total
The chlorine is the same (see this standard 1).
A.2 Principle of the method
After measuring free chlorine and total chlorine, titrate two additional samples.
a) Add one of the samples to the Erlenmeyer flask containing phosphate buffer solution (6.11) and DPD solution (6.12), plus
A small amount of potassium iodide is added, and the reaction is limited to monochloramine in free chlorine and chlorine;
b) In another sample, first add a small amount of potassium iodide, then add phosphate buffer solution (6.11) and DPD solution (6.12).
At this time, free chlorine, monochloramine in the combined chlorine, and 50% nitrogen trichloride react.
The dichloramine in the combined chlorine does not react in either case. Calculate the concentration of monochloramine, dichloramine and nitrogen trichloride in the combined chlorine
degree.
A.3 Reagents and materials
See Standard 6 (Reagents and Materials) and the following reagents.
Potassium iodide solution, ρ(KI) = 5 g/L. It is ready to use and is packed in a brown bottle.
A.4 Instruments and equipment
See this standard 7 (instruments and equipment).
A.5 Analysis steps
A.5.1 Determination of monochloramine in free chlorine and combined chlorine
Add 15.0 ml phosphate buffer solution (6.11), 5.0 ml DPD solution (6.12) and 100 ml to a 250 ml Erlenmeyer flask.
Sample, and add 2 drops (about 0.1 ml) of potassium iodide solution (A.3) or a small crystal of potassium iodide (about 0.5 mg), mix and use immediately.
Ammonium ferrous sulfate standard titration solution (6.9) was titrated to a colorless end. Record the number of milliliters of solution solution volume V6. High concentration samples should be diluted
After the measurement.
A.5.2 Determination of free chlorine, monochloramine in combined chlorine and 50% nitrogen trichloride
Into a 250 ml beaker, add 100 ml of sample, 2 drops (about 0.1 ml) of potassium iodide solution (A.3) or a small amount of potassium iodide.
Crystal (about 0.5 mg), mix. Pour the solution in the beaker into 15.0 ml phosphate buffer solution (6.11) and 5.0 in 1 min.
Mol DPD solution (6.12) in a 250 ml Erlenmeyer flask. Immediately titrate with ammonium ferrous sulfate standard titration solution (6.9) until colorless.
Record the number of milliliters of solution solution volume V7. High concentration samples should be determined after dilution.
A.6 Calculation of results
A.6.1 Calculation of monochloramine
The mass concentration ρ (in terms of Cl 2 ) of monochloramine in the combined chlorine is calculated according to the formula (A.1).
( )
(Cl ) = 70.91
c VV
ρ − × (A.1)
Where. V6--the volume of the standard titration solution of ammonium ferrous sulfate (6.9) was consumed in the measurement (A.5.1), ml.
A.6.2 Calculation of dichloramine
The mass concentration ρ (in terms of Cl 2 ) of the dichloramine in the combined chlorine is calculated according to the formula (A.2).
[ 2 ]
(Cl ) 70.91
c VVV
ρ −= × (A.2)
W...
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