(610e) Separation and Purification of Value-Added Co-Products In Biorefinery

Recently, there has been increasing interests in conversion of biomass to bioproducts including fuels,
chemicals, materials, and heat and power, etc. due to the shortage of fossil fuel and its increasing price, the
requirement of national energy independence, as well as the enviornmental concerns about green house gas
emissions. In order to improve the ovreall technical, economic viability and environmental sustainability of biobased
economy, similar to petroleum refineries, it is important to consider producing multiple products – in
addition to fuels and energy, value added co-products. Number of plant species contain bioactive compounds
or phytochemicals and they can be extracted as value-added co-products prior to biomass conversion.
Extraction and use of phytochemicals have been studied for many years, with more focus on pharmaceuticals
and neutraceuticals from fruits, vegetables, or other food crops/plants, while less research has been done on
saparation of phytochemicals from woody and perennial materials, which can be renewable feedstocks for
biofuel.

Phytochemicals from plants can be used in pharmaceuticals, cosmetics, neutrition, and consumer products.
Carotenoids, polyphenols and flavonols are known phytochemicals that can be used for treatment of a
number of disorders. Phytochemicals from plants are usually present in very dilute quantity. The thermo-liable
or heat-senstive properties of phytochemicals and the increased difficulty of solid-liquid extraction over liquidliquid
extraction bring a great challenge for efficient separation of phytochemicals from dilute biomass matrix.
Thus, selection of suitable solvents and extraction and purification methods for targeted active components
become critically important. In order to help understand various approaches for phytochemicals extraction,
separation and purification, and aid in the development of appropriate methods for value-added co-products,
here we provide an extensive review on the major separation methods suitbale for co-products in
biorefineries. The various separation and purification methods to be considered include solid-liquid extraction
(leaching, ultrasound-assisted extraction, microwave-assisted extraction etc.), steam distillation, pressurized
liquid extraction or near-critical (subcritical) fluid extraction, supercritical fluid extraction, as well as separation
and purification of phytochemicals from dilute solutions or extacts from biorefinery such as liquid-liquid
extraction, vacuum distillation, membrane separation, and molecular distillation, etc.