Sodium Cyanide (CAS 143-33-9)

Grade: Technical / Mining Grade (≥ 98.0% Active Content)

Form Factor: Solid Pillow-Shaped Briquettes (15–20 g) / Liquid Solution

Primary Uses: Precious Metals Extraction (Au/Ag Cyanidation), Pyrite/Sphalerite Flotation Depressant

Sodium Cyanide (NaCN) is the industry-standard lixiviant for hydrometallurgical gold (Au) and silver (Ag) recovery across CIL, CIP, and Heap Leach circuits. Fully certified under the International Cyanide Management Code (ICMC), it guarantees high dissolution kinetics and low insolubles.

Technical Specifications

Parameter	Specification	Standard
Active NaCN Content	≥ 98.0% Min	ISO 6227 Titration
Sodium Hydroxide (NaOH)	0.20% – 0.50% Max	Neutralization Titration
Sodium Carbonate (Na2CO3)	≤ 0.50% Max	Acidimetric Titration
Water Insolubles	≤ 0.05% Max	Gravimetric
Moisture Content (H2O)	≤ 0.50% Max	Karl Fischer
Solubility in Water	370 g/L @ 20°C	Gravimetric

Metallurgical Mechanism & Dosing

Gold Extraction (Elsner Equation)

Precious metal recovery proceeds via oxygenated dissolution:

4 Au + 8 NaCN + O2 + 2 H2O → 4 Na[Au(CN)2] + 4 NaOH

Dosing Rates: 100–500 g/tonne (Standard CIP/CIL); 500–2,000 g/tonne (Sulfidic Ores).
Protective Alkalinity: Slurry pH must be held at 10.5–11.5 using hydrated lime [Ca(OH)2] to prevent toxic hydrogen cyanide (HCN) gas generation (CN⁻ + H2O ⇌ HCN + OH⁻).

Flotation Depressant

Suppresses pyrite (FeS2) and sphalerite (ZnS) in polymetallic Cu-Pb-Zn circuits by forming hydrophilic surface complexes [Fe(CN)6]⁴⁻.

Logistics, EHS & Compliance

Shipping Data: UN 1689 | Class 6.1 (Toxic) | Packing Group I (PG I)
Packaging: 1,000 kg UN-approved wooden boxes with sealed double PE liners or 50 kg steel drums.
Cyanide Detoxification: Residual tailing streams are neutralized using the SO2/Air (INCO) method (CN⁻ + SO2 + O2 + H2O → CNO⁻ + H2SO4) or Hydrogen Peroxide (H2O2).
Certifications: ICMC Signatory, REACH, ISO 9001:2015, ISO 14001:2015, Batch COA verified.