Coconut shell represents one of the newest and most promising options for activated carbon block filters. The density of micro-pores is much higher in coconut than in other forms of activated carbon, meaning it has more surface area and more general porosity. By way of comparison, it contains 50 percent more micro-pores than bituminous coal. This makes coconut better able to adsorb volatile organic chemicals, which are otherwise difficult to remove from water.
Coconut shell carbon’s purity also makes it a better candidate for activated carbon. Whereas other carbons can contribute taste due to inorganic ash, coconut contains a relatively low amount. This creates a more consistent, uniform and non-leaching carbon block that outperforms other options in terms of quality.
Manufacturing coconut shell activated carbon is also easier. Coal and wood both produce significant amounts of dust and fine carbon particles, while coconut produces less of these potential contaminants. Due to this lack of dust, and to the fact that coconut harvesting is a year-round, renewable activity that does not kill trees, this can be considered a green method of obtaining activated carbon.
The benefits of coconut-based activated carbon are as follows:
- They are renewable. Coconuts grow in tropical climates and can be preserved for many years. This makes them able to continuously produce carbon, whereas a tree by itself cannot produce more than one supply of wood in its lifetime.
- They grow throughout the year. Coconuts can be harvested three to four times throughout the year, allowing for steady retrieval of carbon sources.
- They are a green source of carbon. Think of trees as stored carbon. They take carbon dioxide from the atmosphere and store the carbon, producing oxygen in the process. By nurturing coconut trees and continuously using their shells for carbon blocks, that stored carbon is staying in solid form — not burning away into the atmosphere.
- They have high porosity. Additionally, coconut shell activated carbon has a high density of micro-pores, allowing for the best filtering of contaminants.
- They have a tight structure. Another benefit of the microporosity of coconut shell carbon is that it creates high mechanical strength in the carbon. This means increased hardness and good resistance to wear.
- They create cleaner water. The most notable benefit is that coconut shell activated carbon creates the cleanest water of any activated carbon. This is due to its porosity, total pore volume and lack of leaching.