We all like coconuts. But how much do we know about its shells? They are indeed biomass waste and if treated properly, can be very sustainable products.
Like its name, coconut shell activated carbon comes from the coconut shell. To create its activated carbon form, the coconut undergoes a steam activation process. During activation, it creates millions of pores at the surface of the carbon thus increasing the total surface area. Coconut shell carbon has mainly micro-pores to meso-pores and due to its unique distribution of pore diameter; coconut shell activated carbons are very popular in the gas phase purification and potable water purification industries.
Activated carbon manufactured from coconut shell is considered superior to those obtained from other sources, such as wood, coal or peat. This is mainly because of the small macropores structure which renders it more effective for the adsorption of gas/vapour and for the removal of colour and odour of compounds. Indeed, coconut activated carbon has higher iodine number that gives it better adsorption ability for molecules.
The activated carbon is extensively used in the refining and bleaching of vegetable oils and chemical solutions, water purification, recovery of solvents and other vapours, recovery of gold, in gas masks for protection against toxic gases, in filters for providing adequate protection against war gases/nuclear fall outs, etc.
Although steam activation and chemical activation are the two commonly used processes for the manufacture of activated carbon, coconut shell based activated carbon units are adopting the steam activation process to produce good quality activated carbon.