Ordinary activated carbon has limited ability to remove heavy metals solely through physical adsorption; Priority should be given to using modified activated carbon for heavy metal removal. Conventional coconut shell/coal based primary charcoal is only suitable for auxiliary use, and the effect of using ordinary charcoal alone for high concentration heavy metal wastewater is very poor. How to Choose Suitable Activated Carbon for Heavy Metal Removal?

1) Coal based granular activated carbon (most commonly used, cost-effective)

✅  Applicable: Industrial wastewater, surface water, copper, lead, zinc, nickel

Recommendation: Acid washed modified coal activated carbon(acid washed removes iron and aluminum dissolved from the charcoal itself, while increasing surface oxygen-containing functional groups and enhancing ion exchange complexation with heavy metals)

Particle size: 8 *30 mesh/12 *40 mesh (fixed bed filter tank, moderate water flow resistance)

Key indicators:

Iodine value ≥ 900 mg/g (basic pore)

Pickled, low ash content, water soluble heavy metals meet the standard

Surface modification: acidification/sulfurization modification (for chromium and mercury)

2) Coconut shell activated carbon

The pores are mainly micropores, and the adsorption of heavy metals is weaker than that of coal modified carbon

��  Only suitable for low concentration heavy metal+synchronous removal of organic matter scenarios, not recommended as the main treatment carbon for heavy metals

3) Specially modified carbon (for specific heavy metals, high-frequency demand from foreign trade customers)

Sulfurization modified carbon: prioritizes the removal of Hg mercury, Pb lead, and heavy metals to form sulfide precipitates, greatly improving the removal efficiency

Iron oxide/hydroxy iron loaded activated carbon: specifically designed to remove Cr (VI) hexavalent chromium and arsenic As (hexavalent chromium is difficult to adsorb on ordinary activated carbon and must be loaded with iron)