BIOSORPTION OF Pb2+, Cd2+, & Ni2+ FROM WATERS BY ...

3. The metal removal is influenced by the biomass concentration in solution. The
lower quantities of biomass is enough to sequester the metals from the
solution, if the amount of biomass is increased it influences the solution
chemistry of the metals, the activity of the functional groups in the biomass,
and also the compettion between metallic ions. This phenomenon can be
attributed to the interference between the binding sites. This parameter should
be undertaken once biosorption is considered for the removal of metals.
4. Biosorption is utilized to treat wastewater if more than one type of metal ions
would be present. Hence, the presence of other interfering ions can decline the
uptake of the metal which is interested in. In contrast, the presence of Fe 2+ and
Zn 2+ was found to influence uranium uptake by Rhizopus arrhizus (Tsezos
and Volesky 1982) and cobalt uptake by different microorganisms seemed to
be completely inhibited by the presence of uranium, lead, mercury and copper
(Volesky 2007).
5. Cell size and structure , and morphology and also affects the amounts of
metal biosorbed by different biomasses. The greater the cell surface area to
dry weight ratio, the greater the quantity of metal biosorbed by a cell surface
per unit weight.
1.4.3. Advantages of Biosorption
Biosorption has several superiorities over the traditional metal removal
methods that makes it is to be more preferential:
1. Cheap: The cost of biosorbents is low as they often are made from abundant
or waste materials.
2. Metal selective: The metal-sorbing preformance of different types of biomas
can be more or less on different metals. This depends on various factors such
as type of biomass, mixture in the solution, and the type of biomass
preparation.
3. Regenerative: Biosorbent can be reused after the metal is recycled.
4. No sludge generation: No secondary problems with sludge occurs with
biosorption as in the case with many other metal removal technologies.
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