Since activated carbon has been activated, very fine holes (pores) can be seen as shown in the figure below.
These pores are divided into four types: “macropores”, “mesopores”, “micropores”,　and “mesomicropores”.
As shown in the figure below, particles such as organic substances enter the “macropores”　and “mesopores”,　and finer particles enter the “micropores”　and “mesomicropores”.
The mechanism of adsorption by activated carbon is to remove pollutants from raw water by incorporating adsorbents (particles such as organic matter) into the pores.

There are two types of adsorption by activated carbon: “physical adsorption”, “chemical adsorption”　and “physical chemical adsorption”. When activated carbon is used in the liquid phase, removal of organic substances　and odors from TA-30N　and TA-30C, purification of sucrose with bone charcoal, etc. are “physical adsorption”　and “physicochemical adsorption”,　and removal of fluorine from bone charcoal is “physical adsorption”. What is called “chemical adsorption”.

	Physisorption	Chemisorption	Physicochemical adsorption
Adsorption power	Van der Waals force	Ionic bonding, etc.	Surface charge
Selectivity	None	Yes	None
Place to adsorb	Invades pores	Mainly surface	Surface, pores
speed	early	slow	Medium

The most important thing to note about adsorption with activated carbon is that the pore size　and pore distribution of the activated carbon must match the size of the pollutants contained in the raw water.
In the case of TA-30N　and TA-30C handled by our company, the purpose of use is determined as follows based on the pore distribution.
TA-30N: Residual chlorine, odor, organic matter
TA-30C: Humic chromaticity, organic matter (especially wastewater)
However, when using activated carbon for adsorption, we will propose the specifications of activated carbon after receiving the actual raw water, measuring the equilibrium adsorption amount　and investigating the treatment capacity by passing water.