Abstract:
One of the common contaminants of industrial wastewater is dye pollutants
that come from textile, paper and leather industries. Currently much
attention has been paid in utilizing low cost biosorbents for dye removal in
wastewater. The feasibility of utilizing Macaranga indica (MI) leaf powder
as a potential adsorbent for the removal of methylene blue (MB) was
investigated in this study. The parameters such as contact time and pH
were optimized for the determination of adsorption capacity of MI leaf
powder. The surface characterization of the adsorbent was carried out by
determining the point of zero charge (pHpzc) values. Possible enhancement
of adsorption capacities was investigated by the chemical modification
which is one of the most outstanding and efficient techniques used to
enhance the surface properties of biosorbents. NaOH and EDTA were used
for chemical modification of MI leaf powder and the maximum adsorption
capacities were determined. The maximum adsorption capacities for
unmodified MI leaf powder and its NaOH and EDTA modified forms were
12.31, 149.25 and 250.00 mg/g respectively. The extent of the adsorption
of MB by the unmodified and modified MI leaf powder was influenced by
ionic constituents in the medium and pH. Langmuir and Freundlich models
were used to describe the adsorption process. The results revealed that dry
powder of MI leaf is a very efficient low cost potential biosorbent for the
removal of MB and similar cationic dyes from aqueous solutions such as
wastewater.
