Gold CIP (Carbon in Pulp) and Gold CIL (Carbon in Leach) are two of the most widely used cyanide gold extraction processes.
Both technologies are mature, reliable, and capable of achieving high gold recovery — when properly matched with the ore characteristics.

This page explains their core differences, application conditions, and selection logic from an engineering perspective.

What Is the Fundamental Difference Between CIP and CIL?

Although CIP and CIL share the same gold recovery principle, their key difference lies in the timing and position of activated carbon addition.

CIL (Carbon in Leach)

Activated carbon is added directly into the leaching tanks

Gold leaching and carbon adsorption occur simultaneously

CIP (Carbon in Pulp)

Gold leaching is completed first

Activated carbon is added only after leaching, in a separate adsorption circuit

This structural difference affects:

Process flexibility

Suitability for different ore types

Operational stability

Which Process Achieves Higher Gold Recovery?

There is no absolute answer.

Gold recovery is mainly influenced by:

Ore type and mineralogy

Gold particle size and liberation

Leaching kinetics

Carbon activity and management

With proper design and operation, both CIP and CIL can achieve high and comparable gold recovery rates.

The process name itself does not determine recovery — ore behavior does.

When Is the CIL Process More Suitable?

CIL is generally recommended for projects with:

Fast-leaching gold ores

Oxide or low-sulfur ores

Low clay and impurity content

Stable cyanide consumption

Small to medium plant capacity

Why CIL?

Shorter flowsheet

Fewer tanks

Lower initial capital investment

Compact plant layout

CIL works best for simple, easily leachable ores.

When Is the CIP Process a Better Choice?

CIP is preferred when dealing with:

Slow-leaching ores

Complex or variable ore composition

High clay or impurity content

Large-scale or long-term operations

Projects prioritizing stability and control

Advantages of CIP:

Independent control of leaching and adsorption

Flexible adjustment of leaching time

Better protection of activated carbon

Improved long-term operational stability

For complex ores, stability is often more important than simplicity.

Why Is CIP Widely Used in African Gold Plants?

Many African gold deposits are characterized by:

Variable ore quality

Longer leaching time

Higher clay content in some zones

Challenging site operating conditions

CIP is often selected because it offers:

Better process control

Greater tolerance to ore variability

Easier carbon management

More stable long-term operation

This makes CIP a proven and reliable solution for many African gold mining projects.