12
1.6 Physicochemical Characteristics of Activated Carbon
As earlier pointed out, the nature of activated carbon can be easily influenced by its
mode of production and properties of the raw materials used as precursors for its
synthesis. The choice of material, the process used in activation, and factors considered during synthesis will define the physical constituents and general performance
of the produced activated carbon (Leimkuehler 2010). Mohammad-Khah and Ansari
(2009) have shown that among the significant properties of activated carbon, the
constituent of the ash, the phenomenon of the surface chemistry, and the activating
carbon pH are the significant chemical properties of activated carbon.
1.6.1 Physical Characteristics of Activated Carbon
(i) Surface area (m
2
/g): The nature of the surface of activated carbon can be
observed by an electron microscope by revealing its structures. The microscope reveals carbon particles that are extremely complex and porous. Instances
where carbon particles displayed structure that is graphite like and coarse show
that the distance between the particles is barely separated in few nanometers
(Pradhan 2011). The surface area available for adsorption of carbon is usually
Table 1.4 Parameters influencing the performance of activated carbon
Parameter
Unit
Description
References
a
BET surface
area
m
2 /g Textural property as the total surface area
per unit weight of the AC
Müller (2010), Roman
et al. (2013) and
Sudaryanto et al. (2006)
Pore volume m
3 /g Average size of a single void in the AC
consists of micro and mesopores
Alslaibi et al. (2013), Dias
et al. (2007) and Danish
and Ahmad (2018)
Particle size μm or
mm
The finer the particle size, the larger the
surface area of the carbon and possible
increase in microporosity
Alslaibi et al. (2013)
Fractal
dimension
Degree of roughness or irregularity of the
surface of the AC
Dıaz-Dıez et al. (2004),
Hesas et al. (2013) and
Yakout and El-Deen (2016)
Adsorption
capacity
cm
3
/g Performance parameters of AC, determined
via any or all of the followings: adsorption
of methylene blue (MB index), acid blue
29 dye (AB29), phenol adsorption, and N 2
adsorption at 77 K
Dias et al. (2007), Hesas
et al. (2013) and Yahya
et al. (2015)
Yield
% or
gg
−1
Percent of carbon in the precursor that is
left in the AC
Foo and Hameed (2012)
and Alslaibi et al. (2013)
Surface
functional
group
Hydroxyl, carbonyl, amine, and alkenes
Iftekhar et al. (2018) and
Danish and Ahmad (2018)
a
BET - Brunauer–Emmett–Teller, AC – activated carbon
B. Oladipo et al.
1.6 Physicochemical Characteristics of Activated Carbon
As earlier pointed out, the nature of activated carbon can be easily influenced by its
mode of production and properties of the raw materials used as precursors for its
synthesis. The choice of material, the process used in activation, and factors considered during synthesis will define the physical constituents and general performance
of the produced activated carbon (Leimkuehler 2010). Mohammad-Khah and Ansari
(2009) have shown that among the significant properties of activated carbon, the
constituent of the ash, the phenomenon of the surface chemistry, and the activating
carbon pH are the significant chemical properties of activated carbon.
1.6.1 Physical Characteristics of Activated Carbon
(i) Surface area (m
2
/g): The nature of the surface of activated carbon can be
observed by an electron microscope by revealing its structures. The microscope reveals carbon particles that are extremely complex and porous. Instances
where carbon particles displayed structure that is graphite like and coarse show
that the distance between the particles is barely separated in few nanometers
(Pradhan 2011). The surface area available for adsorption of carbon is usually
Table 1.4 Parameters influencing the performance of activated carbon
Parameter
Unit
Description
References
a
BET surface
area
m
2 /g Textural property as the total surface area
per unit weight of the AC
Müller (2010), Roman
et al. (2013) and
Sudaryanto et al. (2006)
Pore volume m
3 /g Average size of a single void in the AC
consists of micro and mesopores
Alslaibi et al. (2013), Dias
et al. (2007) and Danish
and Ahmad (2018)
Particle size μm or
mm
The finer the particle size, the larger the
surface area of the carbon and possible
increase in microporosity
Alslaibi et al. (2013)
Fractal
dimension
Degree of roughness or irregularity of the
surface of the AC
Dıaz-Dıez et al. (2004),
Hesas et al. (2013) and
Yakout and El-Deen (2016)
Adsorption
capacity
cm
3
/g Performance parameters of AC, determined
via any or all of the followings: adsorption
of methylene blue (MB index), acid blue
29 dye (AB29), phenol adsorption, and N 2
adsorption at 77 K
Dias et al. (2007), Hesas
et al. (2013) and Yahya
et al. (2015)
Yield
% or
gg
−1
Percent of carbon in the precursor that is
left in the AC
Foo and Hameed (2012)
and Alslaibi et al. (2013)
Surface
functional
group
Hydroxyl, carbonyl, amine, and alkenes
Iftekhar et al. (2018) and
Danish and Ahmad (2018)
a
BET - Brunauer–Emmett–Teller, AC – activated carbon
B. Oladipo et al.