• Carbonization: Coconut shells are heated in an oxygen-deprived environment, converting them into carbon-rich char.

• Activation: The char is treated with steam or chemicals at high temperatures, creating a highly porous structure with a vast surface area (500-1500 m²/g). This results in a network of micro-, meso-, and macropores.

2. Mechanisms of Purification:

• Adsorption:

  • Physical Adsorption: Contaminants adhere to the carbon surface via van der Waals forces. Coconut shell carbon's microporous structure is effective at trapping small organic molecules (e.g., pesticides, VOCs).

  • Chemical Adsorption: Surface functional groups (oxygen, hydrogen) can chemically bind specific pollutants like chlorine, which reacts to form harmless chloride ions.

• Catalytic Reduction: Breaks down chloramines into ammonia and chloride, which are then adsorbed.

3. Contaminants Removed:

• Organic Compounds: Pesticides, herbicides, VOCs, and tannins.

• Disinfection Byproducts: Chlorine, chloramines, and trihalomethanes (THMs).

• Taste/Odor Compounds: Sulfur compounds (e.g., hydrogen sulfide) and phenols.

• Heavy Metals: Partial removal of lead, mercury, and copper via adsorption (effectiveness varies with pH and carbon treatment).

4. Advantages:

• High Microporosity: Superior for adsorbing small organic molecules compared to coal-based carbon.

• Eco-Friendly: Uses renewable coconut shells, reducing waste.

• Efficiency: Effective at moderate flow rates due to optimal pore structure.

5. Limitations:

• Inorganic Contaminants: Does not remove nitrates, fluoride, or dissolved salts.

• Microorganisms: Ineffective against bacteria/viruses; requires pairing with UV or mechanical filtration.

• Saturation: Requires replacement/regeneration once pores are filled (regeneration typically industrial).

6. Applications:

• Household Filters: Pitcher filters, faucet attachments.

• Industrial Systems: Combined with ion exchange or reverse osmosis for comprehensive treatment.

• Wastewater Treatment: Removes organic pollutants and decolorizes water.

7. Complementary Technologies:

• Reverse Osmosis: Removes inorganics and salts.

• UV Treatment: Disinfects microbes.

• Ion Exchange: Targets heavy metals and hardness ions.