New Generation Material for the Removal of Arsenic from Water - Advanced Materials for Agriculture, Food and Environmental Safety - page 66

Table 3.2 Activated carbons with dif erent parameters.

Adsorbent pH Concentration

range

Capacity (mg/g)
As (III)

Ref.

As(V)

2860

Activated carbon - 300 mg/L [53]

Activated carbon - - 25 [54]

Coconut shell carbon
with 3 % ash

5 0-200 mg/L 2.4 [55]

Activated carbon 3.75 [59]

Coconut husk carbon 12 50-600 mg/L 146.30 - [60]

Activated carbons from
olive pulp and olive
stone, carbon A

7 5-20 mg/L 1.393 - [61]

Activated carbons from
olive pulp and olive
stone, carbon B

- - 0.855 - [61]

Activated carbons from
olive pulp and olive
stone, carbon C

- - 0.738 - [61]

Activated carbons from
olive pulp and olive
stone, carbon D

- - 0.210 - [61]

chars were obtained from fast pyrolysis at 400 and 450 C in an auger-fed

reactor and characterized. Sorption studies were performed at dif erent
temperatures, pHs and solid to liquid ratios in the batch mode. Maximum
adsorption occurred over a pH range of 3-4 for arsenic and 4-5 for
lead and cadmium. h e equilibrium data were modeled with the help of
Langmuir and Freundlich equations. Overall, the data were well i tted with
both the models, with a slight advantage for Langmuir model. h e As(III)
removal followed the order: pine wood char (1.20 μg/g) < oak wood char
(5.85 μg/g) < oak bark char (12.1 μg/g) < pine bark char (12.15 μg/g). h is
study shows that byproduct chars from bio-oil production might be used
as plentiful inexpensive adsorbents for water treatment (arsenic remedia-
tion) at a value above their pure fuel value. Further studies of such chars,
both untreated and at er activation, seem warranted. Part of the ef orts to
generate byproduct value from biorei neries are shown in Table 3.3.

°