GB/T 7746-2023 Anhydrous hydrogen fluoride for industrial use
Warning: According to Clause 6 of GB 12268-2012, this product is a corrosive substance of Category 8, and the secondary hazard is Category 6 toxic substances 6.1. Be careful when operating! If the reagent is splashed on the skin or eyes, rinse it immediately with water. In severe cases, seek medical attention immediately. Persons using this document shall be familiar with normal laboratory practice. This document does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user to establish appropriate safety and health practices and to ensure compliance with any national regulatory conditions.
1 Scope
This document specifies the requirements, test methods, inspection rules, marking and accompanying documents, packaging, transportation and storage of anhydrous hydrogen fluoride for industrial use.
This document is applicable to anhydrous hydrogen fluoride for industrial use.
Note: This product is mainly used as raw material for producing electronic grade hydrofluoric acid, fluorinating agent, fluorohaloalkane, reagent hydrofluoric acid and other fluorine-containing products.
2 Normative references
The following documents contain requirements which, through reference in this text, constitute provisions 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.
GB 190 Packing symbol of dangerous goods
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 judgement of limiting values
HG/T 3696.1 Inorganic chemicals for industrial use - Preparations of standard and reagent solutions for chemical analysis - Part 1: Preparations of standard volumetric solutions
HG/T 3696.2 Inorganic chemicals for industrial use - Preparations of standard and reagent solutions for chemical analysis - Part 2: Preparations of standard solutions for impurity
HG/T 3696.3 Inorganic chemicals for industrial use - Preparations of standard and reagent solutions for chemical analysis - Part 3: Preparations of reagent solutions
3 Terms and definitions
No terms and definitions are listed in this document.
4 Molecular formula and relative molecular mass
Formula: HF.
Relative molecular mass: 20.01 (as per the international relative atomic mass in 2022).
5 Requirements
5.1 Appearance: colorless transparent liquid at low temperature or under certain pressure.
5.2 Anhydrous hydrogen fluoride for industrial use shall be tested with the test methods specified in this document and shall meet the requirements of Table 1.
Table 1 Requirements
Item Index
Superior First-grade Acceptable
Hydrogen fluoride, w/% ≥ 99.990 99.985 99.970
Moisture content, w/% ≤ 0.003 0.005 0.008
Fluosilicic acid, w/% ≤ 0.003 0.005 0.010
Sulfur dioxide, w/% ≤ 0.003 0.005 0.010
Non-volatile acid (counted by H2SO4), w/% ≤ 0.003 0.005 0.010
6 Test methods
6.1 Reagents and products for testing
For the purpose of this document, unless otherwise specified, all the reagents and water used refer to analytical reagents and Grade 3 water specified in GB/T 6682-2008, Table 1. Unless otherwise indicated, standard volumetric solution, impurity standard solution and preparations and products used in test shall be prepared according to those specified in HG/T 3696.1, HG/T 3696.2 and HG/T 3696.3.
6.2 Preparation of laboratory samples
Connect the joint with the plastic nut to the liquid phase tube of the cylinder or tank, open the liquid phase valve of the cylinder or tank, flush the pipeline with liquid hydrogen fluoride for 1min to 2min, and close the liquid phase valve of the cylinder or tank. A mixture of chilled water prepared from distilled water is placed in a plastic bottle of known quality and weighed, to the nearest 0.1g. Insert the plastic tube into the plastic bottle containing the ice water mixture, open the liquid phase valve of the cylinder or tank, and make the liquid hydrogen fluoride slowly pass into the ice water (shaking while passing), so that the hydrogen fluoride gas shall not emerge, until the sample content reaches 20% to 50% (no less than 100g of samples for each bottle), close the liquid phase valve of the cylinder or tank, and weigh, to the nearest 0.1g, the total mass of the plastic bottle again. The same batch of laboratory samples shall be mixed evenly for determination.
The hydrogen fluoride content in laboratory samples can be calculated as mass fraction w1 by using formula (1):
Foreword II
1 Scope
2 Normative references
3 Terms and definitions
4 Molecular formula and relative molecular mass
5 Requirements
6 Test methods
7 Inspection rules
8 Marking and accompanying documents
9 Packaging, transportation and storage
Annex A (Informative) Typical values of moisture working curve
Bibliography
