When it comes to modern gold extraction, CIL (Carbon In Leach) and CIP (Carbon In Pulp) are the two most widely used processes, especially for low-grade ores. While both rely on activated carbon to adsorb gold from cyanide leach solutions, their operational flow and efficiency vary significantly. Choosing the right process—and the right activated carbon for gold extraction—can directly impact your recovery rate, operating cost, and overall productivity.

In this article, we’ll break down the differences between CIL and CIP, analyze their respective advantages, and help you select the most suitable carbon and process based on your ore characteristics and project needs.

What is CIL (Carbon In Leach)?

CIL combines the cyanide leaching and carbon adsorption stages into a single tank. Crushed and ground gold ore is mixed with a cyanide solution and coconut shell activated carbon in the same leaching tank. As gold dissolves into the solution, it is simultaneously adsorbed onto the carbon surface.

✅ Key Advantages of CIL:

Simplified Process: Leaching and adsorption occur in one step, reducing system complexity.

Lower Equipment Investment: Fewer tanks and pipelines are required.

Ideal for Low-Grade or Refractory Ores: Especially effective for ores with inconsistent grade.

Higher Recovery Rates: Often exceeding 90%, making it a popular choice in many gold plants.

Reduced Energy and Operating Cost: Fewer stages mean lower consumption.

⚠️ Potential Drawbacks:

Carbon may suffer from fouling or “poisoning” due to impurities, reducing efficiency.

Larger tanks are needed, with higher mechanical requirements.

For high-grade ores, it might not be as efficient as CIP in terms of recovery speed.

What is CIP (Carbon In Pulp)?

In the CIP process, cyanide leaching and carbon adsorption occur in separate tanks. After the gold is leached into solution, the slurry is pumped into adsorption tanks containing activated carbon to capture the dissolved gold.

✅ Key Advantages of CIP:

Flexible Control: You can adjust leaching and adsorption conditions independently.

More Adaptable Carbon Choices: Allows cost optimization with a broader carbon selection.

Preferred for High-Grade Ores: Efficient and cost-effective for richer ores.

Less Carbon Fouling Risk: Since impurities can be partially removed during pre-leaching.

⚠️ Limitations:

More Equipment Needed: Separate tanks and pumps increase system complexity.

Higher Energy & Maintenance Costs: More moving parts = more upkeep.

Lower Adaptability to Ore Variability: Not ideal for ores with unpredictable composition.

Recovery Rates Can Vary: Especially in lower-grade operations.

Comparison Table: CIL vs CIP

Choosing the Right Activated Carbon

Whether you adopt CIL or CIP, selecting the right activated carbon is critical. Coconut shell activated carbon, with its high hardness, pore volume, and resistance to attrition, is widely regarded as the best carbon for both methods—especially in CIL systems where the carbon is subjected to intense agitation.

Our high-quality coconut shell activated carbon offers:

High adsorption capacity for gold ions

Excellent mechanical strength

Stable performance across various pH and ore conditions

Extended service life, reducing replacement frequency and cost

👉 Learn more about our activated carbon for gold recovery →

Final Thoughts: Which is Better—CIL or CIP?

There’s no one-size-fits-all answer. The best process depends on:

Ore grade and variability

Site infrastructure

Capital budget

Recovery targets

As a general rule:

CIL is better for low-grade or refractory gold ores and projects aiming for high recovery with limited equipment investment.

CIP is better for high-grade ores where flexibility and efficiency are prioritized.

Whichever method you choose, using the right activated carbon is essential for optimizing gold recovery and keeping costs under control.

Need Help Choosing the Right Carbon?

Contact us today to discuss your project and get a free consultation or sample of our gold extraction carbon. We serve mining operations across Africa, South America, and Southeast Asia with reliable carbon solutions tailored to your needs.