Environmental Engineering Reference
In-Depth Information
R
1
OH
O
R
2
O
O
OR
3
Xanthone
25
OH
O
General structure of flavanol
24
OH
O
O
OH
O
O
HO
O
O
O
OH
O
O
O
O
HO
OH
OH
HO
OH
OH
HO
OH
Gallotannin
26
2.5 Concluding Remarks
Within the current state of industry, with non-renewable resources running out
and the cost for waste disposal increasing, waste valorisation is an incredibly
important concept that is beginning to be acknowledged as the future of industrial
waste processing. Biomass including woody waste, marine waste and FSC wastes
are rich in interesting molecules. The techniques for extraction of these chemicals
is still undergoing extensive research to determine the most efficient, selective
and green methods available, and the scaling-up process required to realise an
industrial-scale biowaste biorefinery provides additional difficulties involving
the combination of chemistry, economics and legislation. Although classical sol-
vent extractions are the main quoted method for extraction, more modern and
greener techniques such as microwave-assisted solvent-free supercritical CO
2
and subcritical water extractions are currently being explored as viable alterna-
tives, with positive results indicating the retention of thermally sensitive and
volatile components. The pyrolysis of biomass through microwave treatment has
