GB/T 11212-2026Sodium hydroxide for chemical fibre use (English PDF)

Foreword

This document complies with the provisions of GB/T 1.1-2020 "Standardization Work Guidelines Part

1.Structure and Drafting Rules of Standardization Documents". Drafting. This document replaces GB/T 11212-2013 "Sodium Hydroxide for Chemical Fibers". Compared with GB/T 11212-2013, the main differences are in structural adjustments and compilation. Aside from the logical changes, the main technical changes are as follows:

a) The scope has been changed (see Chapter 1, Chapter 1 of the.2013 edition);

b) The product technical requirements have been changed (see Chapter 5, Chapter 4 of the.2013 edition);

c) The sampling method has been changed (see Chapter 6, Chapter 5 in the.2013 edition);

d) A potentiometric titration method for determining the mass fraction of sodium chloride has been added (see 7.4.1);

e) An ion chromatography method has been added for determining the mass fraction of sodium chloride and sodium sulfate (see 7.4.3);

f) The arbitration method for determining the mass fractions of ferric oxide, silicon dioxide, and copper has been modified (see 7.5, 7.7, and 7.9). (2013 editions 6.5, 6.7, and 6.9)

g) The formula for calculating the mass fraction of calcium by flame atomic absorption spectrometry has been modified (see 7.6.2,.2013 version of 6.6.2);

h) The factory inspection items have been changed (see 8.1.3,

7.1.1 in the.2013 version);

i) Added labels (see 9.2);

j) Added accompanying files (see 9.3);

k) Packaging requirements have been changed (see 10.1,

5 Technical Requirements

5.1 Appearance. Solid products (including flakes, granules, blocks, etc.) are mainly white and glossy; liquid products are colorless and transparent.

5.2 The technical specifications of sodium hydroxide for chemical fibers shall meet the requirements of Table 1.

6 Sampling

6.1 Products shall be inspected in batches. For continuously and stably produced solid sodium hydroxide for chemical fibers, each batch shall be defined as the production volume per day or per production cycle. Sodium hydroxide liquid products for chemical fibers are sold in batches based on the volume contained in each storage tank or tanker truck, or the production volume per shift. Users purchase batches of the same specification and type each time they receive the product. This batch of sodium hydroxide product for chemical fibers constitutes one batch.

6.2 For liquid sodium hydroxide products used in chemical fibers, representative samples of equal amounts shall be taken from the upper, middle, and lower parts of the storage tank or tank truck, in accordance with the provisions of GB/T 6680. For testing, mix the collected samples thoroughly and place them into two clean, dry, stoppered polyethylene bottles, then seal them. One bottle will be used for testing, and the other will be used for backup. Each sample should be tested, and the volume of each sample should be no less than 500 mL.

6.3 For solid sodium hydroxide products used in chemical fibers, random sampling shall be conducted according to the sampling unit number specified in GB/T 6678.After opening the packaging bag, samples shall be taken according to GB/T 6679. According to regulations, representative samples should be taken promptly, the samples should be mixed, and placed in two clean, dry, stoppered polyethylene bottles and sealed. One sample is for testing, and another is for backup testing. Each sample should contain no less than 500g.

6.4 The sample bottle shall be labeled with the name of the manufacturer, product name, model, batch number or production date, sampling date and sampler.

7 Test Methods

7.1 Appearance Visually observe under natural light.

7.2 Determination of the mass fraction of sodium hydroxide It shall be conducted in accordance with the provisions of GB/T 4348.1 or GB/T 11213.1, with GB/T 11213.1 being the arbitration law.

7.3 Determination of Sodium Carbonate Mass Fraction It shall be conducted in accordance with the provisions of GB/T 4348.1 or GB/T 7698, with GB/T 7698 being the arbitration law.

9 Marks, labels and accompanying documents

9.1 Marking The outer packaging of sodium hydroxide products for chemical fibers should have a clear and secure marking, including the manufacturer's name, address, and product information. Name, document number, model, batch number or production date, net weight, and the "corrosive substance" mark specified in GB 190.Hydrogen oxygen for chemical fibers. Sodium chloride solid products should also have the "Avoid rain" mark specified in GB/T 191.

9.2 Tags It should comply with the provisions of GB 15258.

9.3 Accompanying Documents Each batch of sodium hydroxide products for chemical fibers shall be inspected by the manufacturer's quality inspection department according to the requirements of this document, and shall be accompanied by [documentation/documentation]. Quality certification documents include the manufacturer's name, product name, model, quality indicators, batch number or production date, and this document number.