Sodium Cyanide

What Is Sodium Cyanide?

Sodium cyanide, with the chemical formula NaCN, is one of the most vital and widely utilized compounds within the inorganic salts category and the broader inorganic chemicals supply chain. The sodium salt of hydrocyanic acid, it presents as a white, deliquescent solid with a high affinity for water. Due to its exceptional binding affinity for heavy metal ions, sodium cyanide is globally recognized as an indispensable complexing agent in mineral processing.

At the molecular level, the carbon-nitrogen bond in this salt is a triple bond, imparting distinctive reactivity. Handling and storage require rigorous safety protocols owing to its extreme toxicity. In industrial settings, strict control of pH is an absolute prerequisite, as any drop in pH causes the release of lethal hydrogen cyanide gas.

Properties and Physicochemical Characteristics

Sodium cyanide has a molar mass of 49.01 g/mol and a melting point of 563.7 °C. In its pure state, it forms a cubic crystal lattice similar to sodium chloride and emits a faint odor reminiscent of bitter almonds; however, relying on odor for detection is strictly hazardous and prohibited.

Aqueous solutions of this compound are strongly alkaline, as it is the salt of a weak acid and a strong base. Consequently, industrial handling protocols aligned with standard procedures for bases and alkalis must be enforced to maintain solution stability. The high solubility of NaCN in water accelerates solid-liquid extraction kinetics within industrial reactors.

Technical Parameter	Value / Specification
Molecular Formula	NaCN
Molar Mass	49.01 g/mol
Melting Point	563.7 °C
Water Solubility	64 g/100 mL (20 °C)
Physical Form	White briquettes or granules

Industrial Applications of Sodium Cyanide

The primary demand for this compound is concentrated in metallurgical processing and precious metal extraction. Unlike other sodium salts such as sodium nitrite, which serve distinct heat-treatment and corrosion-inhibition roles, NaCN is utilized specifically for gold and silver recovery:

• Gold and Silver Extraction (Cyanidation): In the leaching process, sodium cyanide dissolves precious metals by forming the soluble sodium dicyanoaurate complex, separating gold from the surrounding ore. This remains the most cost-effective method for commercial-scale gold recovery worldwide.
• Electroplating and Metal Finishing: Used in copper, zinc, gold, and silver electroplating baths as an electrolyte to produce smooth, lustrous, and oxidation-resistant coatings.
• Chemical and Pharmaceutical Synthesis: Employed in organic synthesis as a key intermediate for producing nitriles and carboxylic acids.
• Steel Case Hardening: Utilized as an auxiliary chemical in surface heat treatment of steel components to enhance wear resistance.

Safety, Storage, and Hazard Controls

Sodium cyanide is an acutely toxic substance that poses severe risks to human health and the environment. Exposure via ingestion, dust inhalation, or transdermal absorption disrupts cellular oxygen transport, inducing respiratory and central nervous system collapse within minutes.

The most critical chemical hazard arises from contact with acidic conditions. Sodium cyanide must be strictly segregated from mineral acids, as acid-cyanide contact generates immediate, lethal hydrogen cyanide (HCN) gas. Storage facilities must be equipped with continuous toxic gas monitoring sensors, certified ventilation, and emergency eye wash/shower stations. Personnel must wear full-face respirators equipped with certified cartridges and chemical-resistant protective clothing.

Sodium Cyanide Procurement Guide from Moltichem

Procuring this regulated chemical raw material requires working with compliant, verified suppliers. Industrial buyers of sodium cyanide must comply with statutory chemical regulations and provide proper permits for transport, storage, and industrial handling.

Moltichem supplies industrial-grade chemicals with full batch documentation and quality assurance. Industrial procurement specialists, mineral processing facility operators, and electroplating engineers can contact our sales and technical support departments for product specifications, certificates of analysis, and purchase inquiries.