Finding an effective and environmentally acceptable adsorbent is crucial for wastewater treating. Biochar
is a cheap and environmentally friendly adsorbent for Cd that is produced during the pyrolysis of biomass.
Many modification techniques have been employed to increase the adsorption capacity of biochar because it has
a low adsorption ability when it is unmodified due to its poorly porous structure and lack of surface functional
groups. In this study, two types of biochars (orange-shell biochar and pea-shell biochar) and two modifiers
(H2O2 and KMnO4) were prepared. A batch experiment was carried out to evaluate their removing efficiencies
for Cd from a polluted solution. The results showed the adsorption ability of Cd by the above prepared biochar
increased with increasing of their used doses and the highest removal efficiency was noticed due to application
of 1 and 2 g biochars L-1
. KMnO4 modified biochars were better in removing of Cd than H2O2 modified biochars
and both modifiers were better in removing Cd than the unmodified ones. The highest eliminating percentages
of Cd were 91.75% and 93.10% due to the use of KMnO4 pea-shell biochar at levels of 1 and 2 g biochars L-1
.
In view of our results, the H2O2 and KMnO4 modification of orange-shell and pea-shell biochars can be
considered as a promising and non-cost operative sorbent to remove Cd from water/wastewater |
