124
E. Emekdar and U. K. ¸
Sahin
Active biochar/carbon structures that have well-distributed pores, high surface
area, and good surface properties use the physisorption methods but oxygen around
the surface can enhance the absorption according to adsorbate characteristics.
Radaei et al. produced activated carbon with 572.53 m
2 /g surface area from the
waste of pomegranate by using 37% phosphoric acid acids for the removal of Reactive
Blue 19 dyestuffs. Their adsorbent whose amount is 3.5 g/L could adsorb maximum
98.16% dyestuff under conditions with pH 11, 5 min of contact time, and 300 mg/L
initial dyestuff concentration [27].
Kahka and Piri used a waste of citrulluscolosynthis which is a kind of watermelon,
to yield a bio-adsorbent for reactive red dyestuff. The waste of the plant is modified
by using sodium hypochlorite. The best condition for maximum adsorption is with
pH 2, 1.75 g/L initial adsorbent amount, 90 mg/L initial dyestuff concentration, and
70 min of contact time, and they could yield 36 mg/L adsorption capacity [28].
Jin et al. convert municipal solid wastes into biochar by using pyrolysis for
removing arsenic (As(V)) that is a heavy metal. They examined the effects of potassium hydroxide on the activation of biochar. They observed that activated form has
very high adsorption capacity than nonactivated biochar as 30.98 mg/g which is 1.3
times of it because this activation brings functional groups and more surface area to
the pure biochar [71].
Rajapaksha et al. formed biochar with steam activation from an invasive plant
(Sicyos angulatus L.) for sulfamethazine (SMT) in water. They observed that the
most effective parameter is process pH for biochar properties. The best adsorption
which is 37.7 mg/g is yielded at activated one with pH 3, and this capacity referred
to 55% growth compared to pure biochar [74].
Li et al. investigate the formation of biochar from Enteromorpha prolifera (EPAC)
in one step with oily sludge addition for methylene blue dyestuff. With this production, they yielded better surface area, pore, and adsorption capacity as 910 mg/g and
prove the importance of pH levels [75].
Zhang and Lu studied on biochar formation from coconut shell at 450 degree
for 2 h with wet impregnation and calcination for Reactive Brilliant Blue KN-R
remove. Their biochar is modified with TiO 2 , and its crystals are dispersed suitably
and removal ability enhanced than untreated [76].
Ramie bars are used by Cai et al. for removing Safranine T. Their adsorbent is
prepared by pyrolysis of ramie at 500 degree for 20 h after titanium butoxide is
treated. With this modification, pore volume, surface area, and adsorption increase
than pristine biochar thanks to homogenous TiO 2 particles [77].
Chicken feathers are a source of biochar that belongs to Li et al. for Rhodamine B
removal. They used pyrolysis for 1 h at 450 degrees with tetrabutyl titanate treatment.
This method increased surface area and degradation rate due to the TiO 2 particle
surface of biochar [78].
E. Emekdar and U. K. ¸
Sahin
Active biochar/carbon structures that have well-distributed pores, high surface
area, and good surface properties use the physisorption methods but oxygen around
the surface can enhance the absorption according to adsorbate characteristics.
Radaei et al. produced activated carbon with 572.53 m
2 /g surface area from the
waste of pomegranate by using 37% phosphoric acid acids for the removal of Reactive
Blue 19 dyestuffs. Their adsorbent whose amount is 3.5 g/L could adsorb maximum
98.16% dyestuff under conditions with pH 11, 5 min of contact time, and 300 mg/L
initial dyestuff concentration [27].
Kahka and Piri used a waste of citrulluscolosynthis which is a kind of watermelon,
to yield a bio-adsorbent for reactive red dyestuff. The waste of the plant is modified
by using sodium hypochlorite. The best condition for maximum adsorption is with
pH 2, 1.75 g/L initial adsorbent amount, 90 mg/L initial dyestuff concentration, and
70 min of contact time, and they could yield 36 mg/L adsorption capacity [28].
Jin et al. convert municipal solid wastes into biochar by using pyrolysis for
removing arsenic (As(V)) that is a heavy metal. They examined the effects of potassium hydroxide on the activation of biochar. They observed that activated form has
very high adsorption capacity than nonactivated biochar as 30.98 mg/g which is 1.3
times of it because this activation brings functional groups and more surface area to
the pure biochar [71].
Rajapaksha et al. formed biochar with steam activation from an invasive plant
(Sicyos angulatus L.) for sulfamethazine (SMT) in water. They observed that the
most effective parameter is process pH for biochar properties. The best adsorption
which is 37.7 mg/g is yielded at activated one with pH 3, and this capacity referred
to 55% growth compared to pure biochar [74].
Li et al. investigate the formation of biochar from Enteromorpha prolifera (EPAC)
in one step with oily sludge addition for methylene blue dyestuff. With this production, they yielded better surface area, pore, and adsorption capacity as 910 mg/g and
prove the importance of pH levels [75].
Zhang and Lu studied on biochar formation from coconut shell at 450 degree
for 2 h with wet impregnation and calcination for Reactive Brilliant Blue KN-R
remove. Their biochar is modified with TiO 2 , and its crystals are dispersed suitably
and removal ability enhanced than untreated [76].
Ramie bars are used by Cai et al. for removing Safranine T. Their adsorbent is
prepared by pyrolysis of ramie at 500 degree for 20 h after titanium butoxide is
treated. With this modification, pore volume, surface area, and adsorption increase
than pristine biochar thanks to homogenous TiO 2 particles [77].
Chicken feathers are a source of biochar that belongs to Li et al. for Rhodamine B
removal. They used pyrolysis for 1 h at 450 degrees with tetrabutyl titanate treatment.
This method increased surface area and degradation rate due to the TiO 2 particle
surface of biochar [78].