1. Basic Product Information
Chemical Name Potassium Sodium Tartrate Tetrahydrate
Synonyms Rochelle Salt, Seignette’s salt, L‑(+)‑Tartaric acid potassium sodium salt tetrahydrate
CAS Number 6381‑59‑5
EC Number 206‑156‑8Molecular Formula KNaC₄H₄O₆·4H₂O
Molecular Weight 282.22 g/mol
HS‑Code 29181390
2. Chem‑Physical Properties
Appearance Colorless transparent crystal or white crystalline powder
Odor Odorless, taste salty‑bitter
Density 1.79 g/cm³ @20 °C
Melting point 70‑80 °C (loses water of crystallization)
Decomposition temperature 220 °C
Water loss 3 mol H₂O @100 °C; full dehydration @130‑140 °C
pH (5 % aqueous solution,20℃) 7.0‑8.5
Solubility in water ~260 g/L @20 °C, freely soluble
Solubility in ethanol Practically insoluble
Optical rotation [α]D²⁰ +22° (10 % in water)Hygroscopicity Slightly efflorescent in warm air
3. Quality Specification (Industrial / Food Grade)
| Test Item | Unit | Specification | Typical Result | Test Method |
|---|---|---|---|---|
| Appearance | — | Colorless crystal or white crystalline powder | Complies | Visual |
| Assay (KNaC₄H₄O₆·4H₂O) | % | 99.0‑102.0 | 99.7 | Titration |
| pH (5 % water solution) | — | 7.0‑8.5 | 7.8 | Potentiometry |
| Water of crystallization | % | 24.0‑26.0 | 25.1 | Gravimetric |
| Water‑insoluble matter | % | ≤0.01 | 0.004 | Gravimetric |
| Chloride (Cl⁻) | % | ≤0.005 | 0.002 | Turbidimetry |
| Sulphate (SO₄²⁻) | % | ≤0.01 | 0.003 | Turbidimetry |
| Heavy metals (as Pb) | ppm | ≤10 | <5 | AAS |
| Arsenic (As) | ppm | ≤2 | <1 | AAS |
4. Application & Use
Analytical reagent: prepare Fehling’s solution for reducing‑sugar determination, masking agent in chemical analysis.
Food industry: stabilizer, acidity regulator, component of baking powder; used in confectionery & wine processing.
Electroplating: complexing agent for copper plating, silver plating; improves coating quality.
Pharmaceutical: excipient, mild laxative in compound formulations.
Chemical silver‑mirror process: reducing agent for mirror & vacuum‑flask production.Other: piezoelectric crystal raw material, gas desulfurization auxiliary agent.
5. Packing
Standard packing: 25 kg net woven bag with PE inner liner
Small lab package: 1 kg / 5 kg plastic bottleBulk: flexible container bag
6. Storage & Transportation
Storage
Store in cool, dry, well‑ventilated warehouse, keep container tightly closed.
Protect from heat and direct sunlight; avoid warm air (efflorescence risk).
Separated from strong acids, oxidizing substances.
Transportation
Non‑dangerous goods for international transport
Proper shipping name: Potassium Sodium Tartrate Tetrahydrate
Avoid heavy rain & high temperature during transit; prevent package breakage.
chemical.tnj
+8618949823763
tnjchem
2881500864