Sodium Sulfide CAS#1313-82-2
Sodium sulfide is an inorganic chemical compound represented by the formula Na₂S, with its nonahydrate Na₂S·9H₂O being more prevalent in commercial applications. Both the anhydrous form and hydrate are colourless, water‑soluble salts that form highly alkaline aqueous solutions. Upon exposure to humid air, sodium sulfide and its hydrates release hydrogen sulfide gas with a characteristic rotten‑egg odour.
When in contact with moist atmosphere, it absorbs ambient moisture, which may lead to self‑heating and even ignition of adjacent combustible substances. Due to impurity content, technical‑grade sodium sulfide typically appears pink, reddish‑brown or yellowish‑brown.
Sodium Sulfide Chemical Properties
| Melting point | 950 °C(lit.) |
| density | 1.86 g/mL at 25 °C(lit.) |
| storage temp. | Refrigerator (+4°C) |
| solubility | H2O: 0.1 g/mL, clear, colorless |
| form | flakes |
| color | Yellow |
| Specific Gravity | 1.856 |
| Odor | Rotten egg odor |
| Water Solubility | 186 g/L (20 ºC) |
| Sensitive | Hygroscopic |
| Crystal Structure | Reverse CaF2 type |
| crystal system | Cube |
| Merck | 14,8681 |
| Space group | Fm3m |
| Lattice constant | a/nmb/nmc/nmα/oβ/oγ/oV/nm30.6540.6540.6549090900.2797 |
| Dielectric constant | 5.0（Ambient） |
| Stability: | Spontaneously flammable. Incompatible with acids, metals, oxidizing agents. Contact with acid liberates toxic gas. Fine dust/air mixtures are explosive. Hygroscopic. |
| InChIKey | CXPWOVUZRAFMDA-UHFFFAOYSA-N |
| CAS DataBase Reference | 1313-82-2(CAS DataBase Reference) |
| NIST Chemistry Reference | Sodium sulfide(1313-82-2) |
| EPA Substance Registry System | Sodium sulfide (1313-82-2) |
Product Application of Sodium Sulfide
This compound covers diverse application scenarios. Within the dye‑making sector, it supports the manufacture of high‑grade sulfur dyes including sulfur green, sulfur blue and other sulfur‑bearing dyestuffs. It also acts as a solubilizing auxiliary for sulfur‑based dyes during printing and dyeing processes. For the leather industry, it enables depilation and hydrolysis of raw hides. It can further be utilized for preparing sodium polysulfide, which speeds up the soaking and softening of dry hides. Moreover, it functions as an analytical reagent to facilitate leather depilation operations.
