Macro-algae, especially brown algae, are reported as being very
effective biosorbents in the removal of heavy metals from wastewater,
with performances similar to those of commercial ion
exchange resins, and their availability in almost unlimited
amounts in the ocean can be a major factor for their commercialization
[11,28,31–35]. In Portugal, large amounts of brown algae,
such as Ascophyllum nodosum, Fucus spiralis, Laminaria hyperborea
and Pelvetia canaliculata, are found on the beaches, creating an
unpleasant environment for locals and tourists. Therefore, their
application as natural cation exchangers for heavy metals can be
economically attractive.