However, these resources need to be processed to some extent
to be able to be used as raw materials for the preparation of
biocomposites; even natural polymers such as cellulose, chitin, and
starch need first to be extracted from their natural origin and modified accordingly to the desired properties. These processes
will ideally be performed in the near future in an integrated facility,
a so-called biorefinery. Similar to the advent of petrochemical plants
in the 20th century, the 21st century will see a paradigm shift for
energy and chemical production based on biomass in biorefineries
[34]. Biorefineries are integrated operating plants capable of
accepting different streams of biomass feedstock for energy generation
and conversion into valuable chemicals and materials through
different physical, chemical, thermal, and enzymatic processes
[34e36]. Biorefineries for energy and material production must
not compromise at any point the food chain supplies; the choice
of biomass feedstock should therefore involve a wide range of
renewable resources including low value plants, energy crops and
by-products from food crops, sawmills, palm oil production, marine
wastes and food wastes [35]. The operations that may be performed
in a biorefinery facility will involve (i) the extraction of valuable
chemicals from biomass; (ii) the isolation of natural biopolymers and
their further modification; (iii) the hydrolysis of biomass and further
fermentation into so-called bio-platform molecules (bPM) that will
be used as building blocks for value-added chemicals; and (iv)
the use of chemical co-products from fuel biorefineries, thermochemical
conversions of biomass by pyrolysis, or gasification