Industry Guide
Activated Carbon in Gold Mining: CIP vs CIL
Understanding the differences between Carbon-in-Pulp and Carbon-in-Leach processes for gold recovery.
Why Activated Carbon for Gold Recovery?
Activated carbon has been the gold standard (pun intended) for gold recovery since the 1970s. The gold-cyanide complex [Au(CN)₂]⁻ adsorbs strongly onto activated carbon, allowing efficient extraction from leach solutions.
Coconut shell activated carbon dominates this application due to its exceptional hardness (>95%) and high gold loading capacity.
CIP (Carbon-in-Pulp) Process
In CIP, leaching and carbon adsorption are separate stages:
- 1. Ore is ground and leached with cyanide solution
- 2. Leached pulp flows to a series of adsorption tanks
- 3. Activated carbon is added counter-current to pulp flow
- 4. Loaded carbon is removed, stripped, and regenerated
CIP Advantages
- • Better control over leaching conditions
- • Lower carbon inventory required
- • Easier to optimize each stage independently
CIL (Carbon-in-Leach) Process
In CIL, leaching and adsorption occur simultaneously:
- 1. Ore, cyanide, and activated carbon are added together
- 2. Gold dissolves and immediately adsorbs onto carbon
- 3. Reduces preg-robbing losses from carbonaceous ores
- 4. Shorter overall residence time
CIL Advantages
- • Better for preg-robbing ores
- • Simpler circuit design
- • Lower capital cost
- • Faster gold recovery kinetics
Carbon Specifications for Gold Recovery
Critical parameters for gold recovery carbon:
| Parameter | Specification | Why It Matters |
|---|---|---|
| Iodine Number | >1050 mg/g | Indicates adsorption capacity |
| Hardness | >95% | Resists attrition in agitated tanks |
| Particle Size | 6×12 mesh typical | Balance of kinetics and screening |
| Ash Content | <3% | Lower ash = higher activity |
| Moisture | <5% | Affects shipping weight |
CIP vs CIL: Which to Choose?
Choose CIP When:
- • Ore is not preg-robbing
- • Need precise leaching control
- • Existing infrastructure supports it
- • Lower carbon consumption priority
Choose CIL When:
- • Ore contains natural carbon (preg-robbing)
- • Simpler operation preferred
- • New greenfield project
- • Faster recovery needed
Carbon Management Best Practices
- • Regular screening to remove fines
- • Thermal regeneration at 650-750°C
- • Acid wash to remove calcium carbonate buildup
- �� Monitor gold loading (typically 5-15 kg Au/ton carbon)
- • Track carbon losses (target <30 g/ton ore)
Need Gold Recovery Carbon?
We supply premium coconut shell carbon for gold mining with iodine >1100 mg/g and hardness >97%.
Request Quote →