Foreword
This document is drafted in accordance with the provisions of GB/T 1.12020 "Guidelines for Standardization Work Part 1: Structure of Standardization Documents and Drafting Rules".
This document is part 5 of GB/T 5750 "Standard Test Methods for Drinking Water". GB/T 5750 has published the following parts.
Part 1:General Provisions.
Part 2: the collection and preservation of water samples.
Part 3: Quality control of water quality analysis.
Part 4: sensory properties and physical indicators.
Part 5: inorganic non-metallic indicators.
Part 6: metal and metal-like indicators.
Part 7: organic composite indicators.
Part 8: organic indicators.
Part 9: Pesticide indicators.
Part 10: Disinfection by-product indicators.
Part 11: Disinfectant indicators.
Part 12: Microbial indicators.
Part 13: Radioactive indicators
This document replaces GB/T 57505-2006 "standard test methods for drinking water inorganic non-metallic indicators" compared with GB/T 5750.5 a 2006, in addition to structural adjustments and editorial changes, the main technical changes are as follows.
a) increased the "terms and definitions" (see Chapter 3).
b) increased the 8 test methods (see 7.3, 7.4, 11.4, 11,5, 13,4, 14.1, 14.2, 14.3).
c) changed 2 test methods (see 9.113.1, 6.111.1 of the 2006 version).
Changed the names of three indicators, including "nitrate nitrogen" to "nitrate (in N)", "ammonia nitrogen" to "nitrogen (in N) )
d) "nitrite nitrogen" to "nitrite (N)" (see Chapter 8, Chapter 11, Chapter 12, Chapter 5, Chapter 9, Chapter 10 of the 2006 edition).
e) deleted five test methods (see 3.5546.28.111.4 of the 2006 edition). Please note that some of the contents of this document may involve patents. The issuing agency of this document does not assume responsibility for identifying patents This document was proposed and attributed by the National Health and Wellness Commission of the People's Republic of China.
Introduction
GB/T 5750 "Standard Test Methods for Drinking Water" as a recommended national standard for drinking water testing technology, and GB 5749 "Drinking Water Sanitation Standards" supporting the important technical support of GB 5749, for the implementation of GB 5749, to carry out health and safety evaluation of drinking water to provide test methods.
GB / T 5750 consists of 13 parts.
Part 1: General Provisions. The purpose is to provide the basic principles and requirements of water quality testing
Part 2: the collection and preservation of water samples. The purpose is to provide water samples collected, preservation, management, transport and sampling quality control of the basic principles, measures and requirements.
Part 3: Water quality analysis quality control. The purpose is to provide water quality inspection and testing laboratory quality control requirements and methods
Part 4: Sensory traits and physical indicators. The purpose is to provide sensory traits and physical indicators of the corresponding test methods
Part 5: inorganic non-metallic indicators. The purpose is to provide inorganic non-metallic indicators of the corresponding test methods.
Part 6: Metals and metal-like indicators. The purpose is to provide metal and metal-like indicators of the corresponding test methods
Part 7: Organic composite indicators. The purpose is to provide a comprehensive index of organic substances corresponding test methods.
Part 8: organic indicators. The purpose is to provide the corresponding test methods for organic indicators.
Part 9: pesticide indicators. The purpose is to provide the corresponding test methods for pesticide indicators.
Part 10: Disinfection by-products indicators. The purpose is to provide the corresponding test methods for disinfection by-product indicators
Part 11: Disinfectant indicators. The purpose is to provide the corresponding test methods for disinfectant indicators
Part 12: Microbiological indicators. The purpose is to provide the corresponding test methods for microbial indicators
Part 13: radioactive indicators. The purpose is to provide the corresponding test methods for radioactive indicators
1 Scope
This document describes the determination of sulfate, chloride, fluoride, cyanide, nitrate (in N), sulfide, phosphate, (in N) nitrite (in N), iodide, perchlorate in drinking water and water source water sulfate, chloride, fluoride, cyanide (isonicotinic acid - Vishwakarma spectrophotometric method, isonicotinic acid - barbiturate spectrophotometric method), nitrate (in N ), sulfide, phosphate, ammonia (as N) sub-certainty (as N) iodide determination method.
This document applies to the determination of inorganic non-metallic indicators in drinking water and (or) water source water
2 normative reference documents
The following documents constitute the essential provisions of this document through the normative references in the text. Among them, note the date of the reference document, only the date of the corresponding version applies to this document; do not note the date of the reference document, its latest version (including all the revision of the list) applies to this document.
GB/T 5750.1 standard test methods for drinking water Part 1: General Provisions
GB/T 5750.3 standard test methods for drinking water Part 3: Quality control of water quality analysis
GB / T6682 analysis of laboratory water specifications and test methods
3 Terms and definitions
GB / T 5750.1 and GB / T 5750.3 defined terms and definitions apply to this document
4 Sulfate
4.1 Barium sulfate turbidimetric method
4.1.1 Minimum detection mass concentration
The minimum detection mass of this method is 0.25mg, if the 50mL water sample is taken to determine the minimum detection mass concentration of 5mg / L. This method is applicable to the determination of sulfate mass concentration of less than 40mg / L water samples. Stirring speed, time, temperature and reagent addition method can affect the determination of barium sulfate turbidimetric method, therefore requires strict control of the operating conditions consistent.
5 Chloride
5.1 Silver nitrate volumetric method
5.1.1 Minimum detection mass concentration
The minimum detection mass of this method is 0.05mg, if 50mL sample is taken to determine the minimum detection mass concentration of 1.0mg / L. Australide and iodide can cause the same reaction, and the mass of the equivalent of chloride into the results. Sulfide, sulfite, thiosulfate and more than 15mg / L of oxygen consumption can interfere with the determination of this method. Sulfite and other interference can be removed by hydrogen peroxide treatment. Higher oxygen consumption of water samples can be treated with potassium permanganate or steamed dry after ashing.
6 Fluoride
6.1 ion selective electrode method
6.1.1 The minimum detection mass concentration of this method is 2g, if the 10mL water sample is measured, the minimum detection mass concentration of 0.2mg/L. Chromaticity, turbidity and more interfering substances can be directly determined by this method. In order to eliminate the interference of OH~ on the determination, the pH value of the measured water sample is controlled at 5.5~6.5.
7 compounds
7.1 Isonicotinic acid - Vishnu ketone spectrophotometric method
7.1.1 The minimum detectable mass concentration of this method is 0.1g, if 250L water sample is taken for evaporation, the minimum detectable mass concentration is 0.002mg/L. Oxidants such as residual chlorine can destroy cyanide, and 0.1g/L sodium sulfite or less than 0.1g/L sodium thiosulfate can be added to the water sample to remove the interference.
7.1.2 Principle
In the solution of pH=7.0, the cyanide is transformed into cyanuric chloride by chloramine T, and then interacted with isonicotinic acid-ketone (1-phenyl-3-methyl-5-viologen ketone) to produce blue dye for colorimetric quantification.
8 Nitrate (as N)
8.1 Muscimol spectrophotometric method
8.1.1 Minimum detection mass concentration
The minimum detection mass of this method is 0.5g of nitrate (in N), if 1.0 water samples are taken to determine the minimum detection mass concentration of 0.5mg / L.
Nitrite is positive interference with this method, the use of sulfamic acid money to remove: chloride is negative interference with this method, the use of silver sulfate to eliminate sulfide
9 N,N-diethyl-p-phenylenediamine spectrophotometric method
9.1.1 Minimum detection mass concentration
The minimum detection mass of this method is 1.0g, if the 50mL water sample is taken for determination, the minimum detection mass concentration is 0.02g/L.
9.1.2 Principle of sulfide and N,N-diethyl-p-phenylenediamine and ferric chloride to produce a stable blue color, colorimetric quantification at 665nm
9.1.3 Reagent
10 Phosphate
10.1 Phosphorus key blue spectrophotometric method
10.1.1 Minimum detection mass concentration
This method is suitable for the determination of phosphate (HPOF) mass concentration of less than 10mg / L of water samples.
10.1.2 Principle
In a strongly acidic solution of phosphate and acid money to generate phosphorus key heteropolyacid, can be reduced by reducing agents (stannous chloride, etc.) to produce a blue complex, when the phosphate content is low, its color intensity is proportional to the phosphate content.
10.1.3 Reagents
11 ammonia (as N)
11.1 Nah reagent spectrophotometric method
11.1.1 Minimum detectable mass concentration
The minimum detection mass of this method is 1.0g of nitrogen (in N) If a 50L water sample is taken for determination, the minimum detection mass concentration is
0.02mg/L.
12 nitrite (in N)
12.1 diazo coupling spectrophotometry
12.1.1 Minimum detection mass concentration
The minimum detection mass of this method is 0.05g of nitrite (in N) If 50L water samples are taken to determine the minimum detection mass concentration of 0.001mg / L.
Trichloramine in water produces red interference. Iron, lead plasma can produce precipitation caused by interference. Copper ions play a catalytic role in the decomposition of diazo salts to low results. Colored ions have interference.
13 Iodide
13.1 Sulfuric acid pavement catalytic spectrophotometry
13.1.1 Minimum detection mass concentration
Iodide content in the range of 0g / L ~ 20g / L, the minimum detection quality of this method is 2.4ng (to count) if 2.0mL water samples are taken to determine the minimum detection quality concentration of 1.2g / L; g / L ~ 200g / L range detection method minimum detection quality of 1.6ng (to count), if 0.3mL water samples are taken to determine the minimum detection quality concentration of 5.3g / L.
This method is suitable for the determination of iodide in the low concentration range of 0g/L~20g/L and in the high range of g/L~200g/L
14 Perchlorate
14.1 ion chromatography - hydroxide system drenching solution
14.1.1 Minimum detection mass concentration
This method is only used for the determination of perchlorate in domestic drinking water.
