Sodium nitrate

Sodium nitrate (CAS 7631-99-4), also known as Chile saltpeter or E251, is an inorganic salt used in food preservation, agriculture, and industrial oxidation processes.

Where is Sodium nitrate used?

• Food processing: curing agent for processed meats such as bacon, ham, and deli products, inhibiting microbial growth and stabilizing color
• Agriculture: fast-acting nitrogen source in straight and compound fertilizers for crops requiring rapid nutrient uptake
• Mining: oxidizer component in blasting agents and explosive formulations
• Pulp and paper: supports chemical pulping and acts as an oxidizing agent in bleaching and delignification
• It functions as a fertilizer feedstock and oxidizing agent depending on the sector.
• Energy industry: used for heat storage in solar thermal plants as part of liquid salt mixtures.
• Wastewater treatment: used in denitrification, where microorganisms convert nitrate into gaseous nitrogen.

Formulation notes

• Incompatible with cellulose-based absorbents.
• Can be mixed with potassium chloride, natural phosphates, and dicalcium phosphate.

Typical specification

• Offered in technical grade powder form.
• More soluble in water than potassium nitrate and absorbs moisture from the air.

Regulatory status

• Classified under UN transport hazard class 5.1 with packing group III.
• Technical grade is not intended for food or pharmaceutical applications.

Storage, packaging and handling

• Should be stored separately from combustible substances and reducing agents, in a dry place.
• Very hygroscopic and tends to solidify even upon contact with air.
• Should be kept away from combustibles such as wood, paper, and oil.

Frequently asked questions about Sodium nitrate

In which application does sodium nitrate accelerate hardening at low temperatures?

In construction chemistry it accelerates the hardening of concrete at low temperatures.

Technical content is compiled and updated by the SoleChem product team from public technical sources; the certificate of analysis (COA) governs product-specific specifications.