Parameter Category | Specific Indicators (Food Grade / Industrial Grade / Medical Grade) | Description |
Chemical Formula | NaCl | Inorganic ionic compound (sodium + chlorine). |
Appearance | White cubic crystals / fine powder; odorless; salty taste | High-purity forms have uniform particle size; minimal caking if dry. |
Purity | Food Grade: ≥99.5%; Industrial Grade: ≥95.0%; Medical Grade: ≥99.9% | Medical grade meets pharmacopeia standards (e.g., USP, EP); food grade complies with GB 2721. |
Hygroscopicity | Low; absorbs moisture slightly in high humidity (RH > 75%) | May agglomerate lightly but remains usable after crushing. |
Solubility | 35.9g/100mL (20℃, water); insoluble in ethanol/ether | Solubility changes slightly with temperature (stable vs. most salts). |
Melting Point | 801℃ | Stable at room temperature; melts into conductive liquid. |
Boiling Point | 1465℃ | No decomposition before boiling; vaporizes at high temps. |
pH Value (5% Aqueous Solution) | 6.7-7.3 (neutral) | Non-corrosive to common metals; safe for food/medical contact. |
Toxicity | Non-toxic (essential human electrolyte); excess intake may cause health risks | Medical grade is sterile; industrial grade may have impurities (not for consumption). |
Bulk Density | 2.165 g/cm³ (crystals); 1.2-1.3 g/cm³ (powder) | Granular/fine powder forms suit different feeding/processing needs. |
1.Chemical raw material for chlor-alkali industry
Industrial-grade sodium chloride is the primary raw material in chlor-alkali production. Through electrolysis, NaCl is decomposed into chlorine gas (Cl₂), hydrogen gas (H₂), and sodium hydroxide (NaOH)—all critical for manufacturing plastics (e.g., PVC), detergents, and industrial solvents.
2.Road and highway deicing
In winter, industrial-grade sodium chloride is widely used as a road deicer. The compound lowers the freezing point of snow and ice (to around -21℃), accelerating melting; unlike some deicers, NaCl is cost-effective and easy to spread, making it suitable for large-3.scale road maintenance.
Water treatment (wastewater and cooling systems)
Industrial-grade sodium chloride is used in water softening and wastewater treatment. NaCl regenerates ion-exchange resins in water softeners, removing calcium and magnesium ions that cause scale buildup. Additionally, the compound helps adjust the salinity of industrial wastewater, improving the efficiency of purification processes.
4.Metallurgy and metal processing
Industrial-grade sodium chloride acts as a flux in metallurgy. When added to metal ores during smelting, NaCl lowers the melting point of impurities (e.g., silica), helping separate pure metals (e.g., aluminum, zinc) from slag. The compound also prevents metal oxidation by forming a protective layer on the molten metal surface.
5.Textile dyeing and printing auxiliary
In textile factories, industrial-grade sodium chloride enhances dye absorption during fabric dyeing. NaCl increases the affinity of reactive dyes for cotton and other natural fibers, ensuring even color distribution and reducing dye waste. The compound also stabilizes dye solutions, preventing premature precipitation.