From coconut shell to activated carbon

Step by step

• 1. Shell collectionClean shell, with little husk fibre and soil, is gathered and dried. Impurities carry through to the ash number later.
• 2. CarbonizationThe shell is heated without enough air until it becomes charcoal. This is the stage Kora states on its product pages.
• 3. ActivationThe charcoal is treated with steam or carbon dioxide at high temperature, or with a chemical agent, to build fine pores.
• 4. FinishingThe carbon may be washed, dried, crushed and sieved to a mesh range, then tested and packed.
• 5. ReuseSpent carbon can sometimes be regenerated by heating. One large producer lists this as a service.

Under research, not yet verified · General process outline for learning. It is not a Kora process statement and not a specification.

Why coconut shell is used

Coconut shell is dense and gives hard granules, which is why it is a common feedstock for gold, water and air grades. An ICC market review lists India, the Philippines, Sri Lanka and Indonesia as the main producing countries.

In that review, Indonesia exported about 20,077 tonnes of coconut-shell activated carbon in 2017, behind India with 93,868, the Philippines with 70,353 and Sri Lanka with 39,591.

Verified · ICC market review read 2026-10-20. The figures are for 2017 and are dated.

What changes between batches

Shell source, carbonization temperature and time, and activation conditions all move the numbers in the glossary: volatile matter, ash, iodine number, hardness. That is why a number without a date, lab and method is hard to compare.