The standard divides industrial sodium sulfide products into three categories:
Category 1 is ordinary sodium sulfide (commonly known as red alkali);
Category 2 is low-iron sodium sulfide (commonly known as yellow alkali);
Category 3 is high content of sodium sulfide
Ordinary sodium sulfide (enterprise standard)
▼▲
Indicator name
Indicator
Sodium sulfide
Na2S
≥ 50 ~ 60 %
Sodium Sulfite
Na2SO3
≤ 5.0 %
Iron
Fe
≤ 0.15 % (1500ppm)
Water-insoluble matter content
-
≤ 0.4 %
Appearance
-
Brown-red flakes and granules
Low iron sodium sulfide (enterprise standard)
▼▲
Indicator name
Indicator
Sodium sulfide
Na2S
≥ 50 ~ 60 %
Sodium sulfite
Na2SO 3
≤ 2.00 %
Sodium thiosulfate
Na2S2O3
≤ 2.00 %
Iron
Fe
≤ 0.015 % (150ppm)
Sodium carbonate
Na2CO 3
≤ 2.00 %
Water-insoluble matter content
-
≤ 0.20 %
Appearance
-
Yellow flakes and granules
Low iron sodium sulfide (enterprise standard)
▼▲
Indicator name
Indicator
Sodium sulfide
Na2S
≥ 50 ~ 60 %
Sodium sulfite
Na2SO 3
≤ 2.00 %
Sodium thiosulfate
Na2S2O3
≤ 2.00 %
Iron
Fe
≤ 0.012 % (120ppm)
Sodium carbonate
Na2CO 3
≤ 2.00 %
Water-insoluble matter content
-
≤ 0.20 %
Appearance
-
Yellow flakes and granules
Low iron sodium sulfide (enterprise standard)
▼▲
Indicator name
Indicator
Sodium sulfide
Na2S
≥ 50 ~ 60 %
Sodium sulfite
Na2SO 3
≤ 1.00 %
Sodium thiosulfate
Na2S2O3
≤ 2.00 %
Iron
Fe
≤ 0.01 % (100ppm)
Sodium carbonate
Na2CO 3
≤ 2.00 %
Water-insoluble matter content
-
≤ 0.05 %
Appearance
-
Yellow flakes and granules
Low iron sodium sulfide (enterprise standard)
▼▲
Indicator name
Indicator
Sodium sulfide
Na2S
≥ 50 ~ 60 %
Sodium sulfite
Na2SO 3
≤ 2.00 %
Sodium thiosulfate
Na2S2O3
≤ 2.00 %
Iron
Fe
≤ 0.008 ≤
High content of sodium sulfide (enterprise standard)
▼▲ Indicator name Indicator Sodium sulfide Na2S ≥ 65-70 % Sodium carbonate Na2CO3 ≤ 5.0 % Iron Fe ≤ 0.15 % (1500ppm) Water-insoluble matter content - ≤ 0.40 % Appearance - ≤ Brown-red solid
Liquid sodium sulfide (enterprise standard)
▼▲ Indicator name Indicator Sodium sulfide Na2S ≥ 30 % Iron Fe ≤ 0.15 % (1500ppm) Sodium carbonate Na2CO 3 ≤ 3.0 % Water-insoluble matter content - ≤ 0.4 %
Sodium sulfide Na2S ≥ 30 % Iron Fe ≤ 0.15 % (1500ppm) Sodium carbonate Na2CO 3 ≤ 3.0 % Water-insoluble matter content - ≤ 0.4 %