GB/T 23937-2020Sodium hydrosulfide for industrial use (English PDF)

Foreword

This Standard was drafted in accordance with the rules given in GB/T 1.1-2009.

This Standard replaces GB/T 23937-2009, "Sodium hydrosulfide for industrial use"; compared with GB/T GB/T 23937-2009, the main technical changes, except editorial changes, are as follows.

-- Adjust the classification to 4 specifications, namely 32% (liquid), 38% (liquid), 43% (liquid) and 70% (solid) (see Chapter 5; Chapter 5 of version

2009);

-- Add indicators for sodium carbonate, sodium thiosulfate, and sodium sulfite (see Chapter 5);

-- Modify the detection method for sodium sulfide and sodium hydrosulfide contents; add the detection method for sodium carbonate content (see 6.3, 6.3 of version 2009);

-- Add the detection method for sodium sulfite and sodium thiosulfate contents (see 6.4);

-- Modify the detection method for iron content (see 6.5; 6.4 of version 2009);

-- Modify inspection rules (see Chapter 7; Chapter 7 of version 2009);

-- Modify the packaging and storage contents (see Chapter 9; Chapter 9 of version 2009);

1 Scope

This Standard specifies the classification, technical requirements, test methods, inspection rules, marking, labeling, packaging, transportation and storage of sodium hydrosulfide for industrial use.

This Standard applies to sodium hydrosulfide for industrial use, which is mainly used in industries such as mineral processing, pesticides, leather making, dyes, organic synthesis and water treatment.

2 Normative references

The following documents are indispensable for the application of this document.

For dated references, only the dated version applies to this document. For undated references, the latest edition (including all amendments) applies to this document.

GB 190, Packing symbol of dangerous goods

GB/T 191-2008, Packaging - Pictorial marking for handling of goods

GB/T 3049-2006, Chemical products for industrial use - General method for determination of iron content - 1,10-Phenanthroline spectrophotometric method

GB/T 6678, General principles for sampling chemical products

GB/T 6679, General rules for sampling solid chemical products

GB/T 6680, General rules for sampling liquid chemical products

GB/T 6682-2008, Water for analytical laboratory use - Specification and test methods

GB/T 8170, Rules of rounding off for numerical values & expression and judgment of limiting values

3 Molecular formula and relative molecular mass Molecular formula. NaHS

Relative molecular mass. 56.06 (according to the international relative atomic mass in 2018)

4 Classification

Sodium hydrosulfide for industrial use is divided into 4 specifications. 32% (liquid), 38% (liquid), 43% (liquid) and 70% (solid).

5 Technical requirements

The technical requirements of sodium hydrosulfide for industrial use shall meet the requirements of Table 1.

6 Test methods

6.3 Determination of sodium sulfide, sodium hydrosulfide and sodium carbonate contents

6.5 mL of hydrogen peroxide solution while stirring in a fume hood; continue to stir for 1 min.

7 Inspection rules

7.2 Products which are produced with the same materials and basically the same production conditions continuously or in the same group, by the production enterprise, are the same batch. Each batch of solid products does not exceed 60 t; liquid products are determined according to the size of the storage container.

7.3 Determine the number of sampling units and sampling method in accordance with the provisions of GB/T 6678, GB/T 6679, and GB/T 6680. Mix at least 200 g of liquid or 100 g of solid samples evenly; then, put them in two clean and dry sample bottles or sample bags respectively; label them, marking.

7.4 When any indicator of the inspection result does not meet the requirements of this Standard, it shall sample from double the packages for re-inspection; If any indicator the re-inspection result does not meet the requirements of this Standard, the whole batch of products shall be judged as unqualified.

8 Marking, labeling

8.1 The packaging container of sodium hydrosulfide for industrial use shall have clear, obvious, and firm marking, including. manufacturer name, site, product name, specification, net content, batch number or production date, and the number of this Standard, as well as the label of "corrosive material" that is specified in GB 190, and the labels of "afraid of sun" and "afraid of rain" that are specified in GB/T 191-2008.

8.2 Each batch of delivered sodium hydrosulfide for industrial use shall be accompanied by a safety technical specification and a quality certificate. The content of the quality certificate includes.

9 Packaging, transportation and storage