GB/T 25789-2023
p-Phenylenediamine (English Version)
- Standard No.
- GB/T 25789-2023
- Language
- Chinese, Available in English version
- Release Date
- 2023
- Published By
- General Administration of Quality Supervision, Inspection and Quarantine of the People‘s Republic of China
- Latest
- GB/T 25789-2023
- Replace
- GB/T 25789-2010
- Introduction
Interpretation of the National Standard of the People's Republic of China GB/T 25789-2023
Standard Overview
GB/T 25789-2023 "p-Phenylenediamine" is the national standard of the People's Republic of China, which is used to regulate the quality requirements, safety information, sampling, test methods, packaging and storage of p-Phenylenediamine products. This standard replaces the old version GB/T 25789-2010. The main updates include:
- Changes to the quality requirements for p-phenylenediamine (Chapter 4)
- Adjustments to the sampling volume regulations (Chapter 6)
- Optimization of appearance evaluation method (7.2)
- Addition of capillary melting point method (7.3.2)
- Improvement of chromatographic operating conditions (7.4.4)
Quality Requirements Comparison Table
Serial number Item Indicator Test method chapter number Superior product First-class product Qualified products 1 Appearance White to light red crystals Off-white to gray-brown crystals Yellow-brown to gray-brown crystals 7.2 2 Initial melting point ≥139.0 °C ≥139.0 °C ≥137.0 °C 7.3 Analysis of test methods
The standard specifies a variety of test methods, including:
- Capillary liquid bath method (arbitration method): used to determine the initial melting point.
- Gas chromatography: used for quantitative analysis of the purity of p-phenylenediamine and organic impurities.
Among them, the specific operating conditions of gas chromatography are shown in Table 2:
Control parameters Operating conditions Carrier gas High purity nitrogen Detector temperature/°C 300 Safety Information and Protection Recommendations
According to GB12268-2012, p-phenylenediamine is a Class 6.1 toxic substance, and the dangerous goods number is UN:1673. When using and handling:
- Wear protective equipment
- Avoid direct contact
- Strictly abide by storage regulations
Implementation recommendations
To ensure the effective implementation of the standard, it is recommended to:
- Strictly follow the sampling regulations
- Use
capillary melting point instrument to perform initial melting point detection - Standardize the calibration and maintenance of gas chromatographs
- Strengthen employee safety training
GB/T 25789-2023 Referenced Document
- GB 12268-2012 List of dangerous goods
- GB 12463 General specifications for transport packages of dangerous goods
- GB 15258 General rules for preparation of precautionary label for chemicals
- GB 15603 General rules for the hazardous chemicals warehouse storage
- GB/T 16483 Safety data sheet for chemical products.Content and order of sections
- GB/T 8170-2008 Rules of rounding off for numerical values & expression and judgement of limiting values
- GB/T 9722-2006 Chemical reagent.General rules for the gas chromatography
GB/T 25789-2023 history
- 2023 GB/T 25789-2023 p-Phenylenediamine
- 2010 GB/T 25789-2010 ρ-Phenylenediamine
