Standard No.:	HG/T 2520-2023
English Name:	Industrial phosphorous acid
Chinese Name:	工业亚磷酸
Professional Classification:	HG    Professional Standard - Chemistry
Source Content Issued by:	Ministry of Industry and Information Technology
Issued on:	2023-12-29
Implemented on:	2024-7-1
Status:	valid
Superseding:	HG/T 2520-2006 Phosphorous acid for industrial use
Target Language:	English
File Format:	PDF
Word Count:	6000 words
Translation Price(USD):	180.0
Delivery:	via email in 1~2 business day

Phosphorous acid for industrial use Warning: This product belongs to Category 8 corrosive substances according to Clause 8 of GB12268-2012, and shall be handled with care. 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 typing, requirements, test methods, inspection rules, marking, labeling and accompanying documents, packaging, transportation and storage of phosphorous acid for industrial use. This document is applicable to phosphorous acid for industrial use. Note: This product is mainly used as a raw material for the production of phosphite, synthetic fibers, and organic phosphorus pesticides, as well as for the production of nitrilotrimethylene triphosphonic acid, an efficient treatment agent of water. 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 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 3050-2000 Inorganic chemical products for industrial use - General method for determination of chloride content - Potentiometric method GB/T 6678 General principles for sampling 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 GB 12268-2012 List of dangerous goods 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 Molecular formula: H3PO3 Relative molecular mass: 82.00 (as per the international relative atomic mass in 2022)

Contents Foreword i 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 Labeling, marking and accompanying documents 9 Packaging, transport and storage