Surimi wash water treatment by chitosan-alginate complexes

including radioisotopes, has been tested in wastewater treatment processes. Nuclear
fission products such as titanium, zirconium, hafnium, niobium, ruthenium, and
uranium can be effectively recovered using chitin or chitosan (Muzzarelli, 1977).
For example, a liter of tap water adjusted to pH 3.1 using HINO3 and contaminated
with 1.32 tg ruthenium can be treated at 2 ml/min flow rate at 20 °C and made free
of this radioactive material using a chitin or chitosan column (12 x 1 cm). In
decontamination studies conducted on the waste water from the Marcoule Nuclear
Center, France, both chitosan and chitin columns were successful in removing 86%
and 54% of 95zirconium and niobium, respectively. Muzzarelli (1977) showed that
94-97% of 233uranium present in an aqueous solution (50 ml, containing 4.2 j.tg Ur)
can be adsorbed by 200 mg chitosan.
Chitosan can also complex methyl mercury acetate from industrial water or
ionic mercury from tap water (Muzzarelli & Isoalti, 1971). Separation of
manganese and ferrous ions from nickel and copper can be also carried out by
passing the solution through a chitosan sulfate column (Muzzarelli, 1974).
2.5.6. Other applications
Due to its resistance to abrasion, optical characteristics, and film forming
ability, chitosan has important applications in photography. Chitosan can easily
release silver complexes which are used in photography so that it can easily
penetrate from one film layer to another by the diffusion transfer reversal process
(Muzzarelli, 1977).
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