Sodium disulfite

(sodium metabisulfite) EMPROVE® ESSENTIAL Ph Eur,BP,JP,NF,E 223

Sodium disulfite, Sodium metabisulfite, Sodium pyrosulfite, Disulfite, Pyrosulfite
Empirical Formula (Hill Notation):
CAS Number:
Molecular Weight:
MDL number:
E Number:
EC Index Number:
Pricing and availability is not currently available.

storage conditions

Store at +5°C to +30°C.

Quality Level


Ph. Eur.

product line

EMPROVE® Essential


1540 mg/kg LD50, oral (Rat)
>2000 mg/kg LD50, skin (Rat)


3.5-5 (20 °C, 50 g/L in H2O)


150 °C (decomposition)


2.36 g/cm3 at 20 °C

bulk density

1000‑1200 kg/m3



Inchi Key



The specification of the product is part of the Emprove® Material Qualification Dossier and can be found under "General Properties".

Analysis Note

Assay (iodometric): 97.0 - 100.0 %
Assay (iodometric, SO₂): 65.4 - 67.4 %
Identity: passes test
Appearance of solution: passes test
pH-value (5 %; water): 3.5 - 5.0
Chloride (Cl): ≤ 0.01 %
Heavy metals (as Pb): ≤ 0.001 %
Thiosulfate (S₂O₃): ≤ 0.05 %
As (Arsenic): ≤ 0.0002 %
Fe (Iron): ≤ 0.0005 %
Hg (Mercury): ≤ 0.0001 %
Pb (Lead): ≤ 0.0002 %
Se (Selenium): ≤ 0.0003 %
Residual solvents (Ph Eur/USP/ICH): excluded by the manufacturing process
Elemental impurity specifications have been set considering ICH Q3D (Guideline for Elemental Impurities). Class 1-3 elements are not likely to be present above the ICH Q3D option 1 limit, unless specified and indicated (*).
Conforms to the purity criteria on food additives according to the current European Commission Regulation.
Conforms to Ph Eur, BP, JP, NF, E223

Legal Information

Emprove is a registered trademark of Merck KGaA, Darmstadt, Germany

What is the Emprove® Program?

The Emprove® Program is a system providing comprehensive and thorough documentation of our filters and single-use components, pharma raw materials, and starting materials.

Material Qualification Dossier

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