News Details

September 1, 2026, marks the implementation of China's revised national standard GB/T 631—2026 Chemical Reagent—Ammonia Solution, replacing GB/T 631—2007. The updated standard introduces technical requirements for high-purity ammonia solution, incorporates advanced analytical methods such as ion chromatography and inductively coupled plasma techniques, and updates packaging and labeling requirements. The revision reflects growing demand for ultra-high-purity chemical reagents in industries such as semiconductors, pharmaceuticals, and advanced materials. 

Introduction of High-Purity Ammonia Solution Specifications 

A major change introduced by GB/T 631—2026 is the establishment of technical specifications for high-purity ammonia solution, in addition to the existing grades of guaranteed reagent, analytical reagent, and chemically pure reagent. 

The new standard specifies that high-purity ammonia solution shall contain: 

• 25–28% ammonia (NH₃)  

• Evaporation residue: ≤10 mg/kg  

• Chloride: ≤0.05 mg/kg  

• Sulfate: ≤0.1 mg/kg  

• Phosphate: ≤0.1 mg/kg  

• Carbonate (as CO₂): ≤10 mg/kg  

• Potassium permanganate reducing substances (as O): ≤8 mg/kg  

The revised standard also establishes impurity limits for more than 30 elemental contaminants, including: 

• Sodium (Na)  

• Potassium (K)  

• Calcium (Ca)  

• Iron (Fe)  

• Copper (Cu)  

• Lead (Pb)  

• Mercury (Hg)  

• Arsenic (As)  

• Nickel (Ni)  

• Chromium (Cr)  

• Silicon (Si)  

Most trace elemental impurities are restricted to ≤0.001 mg/kg, supporting the increasingly stringent purity requirements of high-end manufacturing sectors. 

Advanced Analytical Methods Added to the Standard 

To improve analytical precision and support ultra-trace impurity analysis, GB/T 631—2026 introduces several advanced instrumental testing methods. 

Newly Introduced Analytical Techniques 

• Ion Chromatography (IC) for the determination of:  

• Chloride  

• Sulfate  

• Phosphate  

• Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES) for the determination of:  

• Sodium  

• Magnesium  

• Potassium  

• Calcium  

• Iron  

• Copper  

• Lead  

• Inductively Coupled Plasma Mass Spectrometry (ICP-MS) for the determination of:  

• Ultra-trace metallic and elemental impurities  

These methods complement traditional analytical procedures and provide enhanced sensitivity for high-purity applications. 

Updated Packaging and Safety Labeling Requirements 

The revised standard updates packaging and labeling provisions to align with current chemical safety requirements. 

Key requirements include: 

• Packaging and marking in accordance with GB 15346 Packaging and Marking of Chemical Reagents  

• Safety labeling in accordance with GB 15258 Rules for Preparation of Precautionary Label for Chemicals  

• Classification of ammonia solution as a corrosive substance  

• A maximum limited quantity packaging volume of 5 liters, in accordance with GB 28644.2 Limited Quantities and Packaging Requirements for Dangerous Goods  

For high-purity ammonia solution, the standard specifies the use of: 

• Polyethylene (PE) containers, or  

• Perfluoroalkoxy (PFA) integrated containers  

to minimize contamination risks. 

Key Changes Compared with GB/T 631—2007 

Compared with the previous edition, GB/T 631—2026 introduces several significant revisions: 

• Addition of technical requirements for high-purity ammonia solution  

• Introduction of ion chromatography methods for anion analysis  

• Introduction of inductively coupled plasma atomic emission spectrometry and inductively coupled plasma mass spectrometry methods for elemental analysis  

• Expansion of impurity control requirements  

• Revision of packaging, transportation, and labeling provisions  

Implementation Date 

The revised standard GB/T 631—2026 Chemical Reagent—Ammonia Solution was issued by the State Administration for Market Regulation of the People's Republic of China and the Standardization Administration of China, and will officially enter into force on September 1, 2026. 

The implementation of this revised standard is expected to strengthen quality control requirements for chemical reagents in China and support the growing demand for ultra-high-purity chemicals in advanced manufacturing and scientific research applications.