Ministry of Agriculture of the People's Republic of China
Issued on:
2017-12-22
Implemented on:
2018-6-1
Status:
valid
Language:
English
File Format:
PDF
Word Count:
4000 words
Price(USD):
120.0
Delivery:
via email in 1 business day
Water-soluble fertilizers - Determination of alginic acid content
1 Scope
This standard specifies the m-hydroxybiphenyl spectrophotometry test method for the determination of alginic acid (algin) content in water-soluble fertilizers.
This standard is applicable to liquid or solid water-soluble fertilizers made from Laminaria japonica, Sargassum, Ascophyllum nodosum and other brown algae through biological, chemical and physical extraction and processing. This method is not applicable to water-soluble fertilizers containing nitrate radical, humic acids and other substances interfering the colorimetric process.
Annex A hereto lists the carbazole-sulfuric acid spectrophotometry test method for the determination of alginic acid content.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
HG/T 3696 Inorganic chemicals for industrial use - Preparations of standard and reagent solutions for chemical analysis
NY/T 887 Liquid fertilizers - Determination of density
3 Principle
Polyhexuronic acid can react with m-hydroxybiphenyl to form a purplish red compound in the presence of sulfuric acid containing sodium tetraborate. Then measure its absorbance at a wavelength of 520 nm. In a certain concentration range, the absorbance of the compound is in direct proportion to the concentration of uronic acid which, therefore, can be determined by spectrophotometry.
4 Reagents and materials
For the purpose of this standard, unless otherwise specified as to the specification or the preparation method, the preparation of the reagents, water, and solutions shall comply with those specified in HG/T 3696.
4.1 Concentrated sulfuric acid: guaranteed reagent.
4.2 Sodium tetraborate-sulfuric acid solution, c(Na2B4O7•10H2O) = 0.012 5 mol/L. Accurately weigh 0.478 g of the sodium tetraborate decahydrate with a 100-mL beaker, then dissolve it with concentrated sulfuric acid (4.1), and then transfer it to a 100-mL volumetric flask and dilute to constant volume with concentrated sulfuric acid (4.1).
4.3 Sodium hydroxide solution: ρ(NaOH)=5 g/L.
4.4 m-hydroxybiphenyl solution: ρ(C12H10O)=1.5 g/L. Weigh 0.15 g of m-hydroxybiphenyl, then dissolve it in 100 mL of sodium hydroxide solution (4.3), and then put it in a brown bottle and store it in a dark place.
4.5 Sodium alginate standard solution: ρ(Sodium alginate) = 0.100 g/L. Accurately weigh 0.100 g of sodium alginate with a 100-mL beaker, then dissolve it with water, and then transfer it to a 1,000-mL volumetric flask and dilute to constant volume with water.
Foreword i
1 Scope
2 Normative references
3 Principle
4 Reagents and materials
5 Instruments
6 Analytical procedure
7 Expression of analysis results
8 Tolerance
9 Conversion of mass concentration
Annex A (Informative) Carbazole-sulfuric acid spectrophotometry test method for determination of alginic acid content
NY/T 3174-2017 Water-soluble fertilizers-Determination of alginic acid content (English Version)
Standard No.
NY/T 3174-2017
Status
valid
Language
English
File Format
PDF
Word Count
4000 words
Price(USD)
120.0
Implemented on
2018-6-1
Delivery
via email in 1 business day
Detail of NY/T 3174-2017
Standard No.
NY/T 3174-2017
English Name
Water-soluble fertilizers-Determination of alginic acid content
Chinese Name
水溶肥料 海藻酸含量的测定
Chinese Classification
G20
Professional Classification
NY
ICS Classification
Issued by
Ministry of Agriculture of the People's Republic of China
Issued on
2017-12-22
Implemented on
2018-6-1
Status
valid
Superseded by
Superseded on
Abolished on
Superseding
Language
English
File Format
PDF
Word Count
4000 words
Price(USD)
120.0
Keywords
NY/T 3174-2017, NY 3174-2017, NYT 3174-2017, NY/T3174-2017, NY/T 3174, NY/T3174, NY3174-2017, NY 3174, NY3174, NYT3174-2017, NYT 3174, NYT3174
Introduction of NY/T 3174-2017
Water-soluble fertilizers - Determination of alginic acid content
1 Scope
This standard specifies the m-hydroxybiphenyl spectrophotometry test method for the determination of alginic acid (algin) content in water-soluble fertilizers.
This standard is applicable to liquid or solid water-soluble fertilizers made from Laminaria japonica, Sargassum, Ascophyllum nodosum and other brown algae through biological, chemical and physical extraction and processing. This method is not applicable to water-soluble fertilizers containing nitrate radical, humic acids and other substances interfering the colorimetric process.
Annex A hereto lists the carbazole-sulfuric acid spectrophotometry test method for the determination of alginic acid content.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
HG/T 3696 Inorganic chemicals for industrial use - Preparations of standard and reagent solutions for chemical analysis
NY/T 887 Liquid fertilizers - Determination of density
3 Principle
Polyhexuronic acid can react with m-hydroxybiphenyl to form a purplish red compound in the presence of sulfuric acid containing sodium tetraborate. Then measure its absorbance at a wavelength of 520 nm. In a certain concentration range, the absorbance of the compound is in direct proportion to the concentration of uronic acid which, therefore, can be determined by spectrophotometry.
4 Reagents and materials
For the purpose of this standard, unless otherwise specified as to the specification or the preparation method, the preparation of the reagents, water, and solutions shall comply with those specified in HG/T 3696.
4.1 Concentrated sulfuric acid: guaranteed reagent.
4.2 Sodium tetraborate-sulfuric acid solution, c(Na2B4O7•10H2O) = 0.012 5 mol/L. Accurately weigh 0.478 g of the sodium tetraborate decahydrate with a 100-mL beaker, then dissolve it with concentrated sulfuric acid (4.1), and then transfer it to a 100-mL volumetric flask and dilute to constant volume with concentrated sulfuric acid (4.1).
4.3 Sodium hydroxide solution: ρ(NaOH)=5 g/L.
4.4 m-hydroxybiphenyl solution: ρ(C12H10O)=1.5 g/L. Weigh 0.15 g of m-hydroxybiphenyl, then dissolve it in 100 mL of sodium hydroxide solution (4.3), and then put it in a brown bottle and store it in a dark place.
4.5 Sodium alginate standard solution: ρ(Sodium alginate) = 0.100 g/L. Accurately weigh 0.100 g of sodium alginate with a 100-mL beaker, then dissolve it with water, and then transfer it to a 1,000-mL volumetric flask and dilute to constant volume with water.
Contents of NY/T 3174-2017
Foreword i
1 Scope
2 Normative references
3 Principle
4 Reagents and materials
5 Instruments
6 Analytical procedure
7 Expression of analysis results
8 Tolerance
9 Conversion of mass concentration
Annex A (Informative) Carbazole-sulfuric acid spectrophotometry test method for determination of alginic acid content