Duck feathers were washed with water, dried and cut into small
pieces. The different weight ratios of IL, duck feathers, Na2SO3, and
water were put into beakers and heated to fixed temperatureis the SEM images of the residual feathers at different
time, showing the microscopic structures. As for the untreated
feather (i.e., 0 min), the surface is very smooth and this is the reason
that the hydrolysis is difficult. With increasing time, the
smooth surface was destroyed. At 20 min, the outline of feather
could be seen, whereas, at 40 min, the structure of residual feather
was almost completely destroyed.
As for the keratin–IL solution, the keratin precipitated out when
adding some water (Fig. 3). The SEM image of extracted keratin is
also shown in Fig. 3 and the keratin does not have the compact
structure of the feathers. Therefore, besides the direct application
of keratin, because the pure keratin with loose structure is greatly
easier hydrolysis than feather, the hydrolysis of keratin to produce
amino acid with eco-friendly method such as enzymatic catalysis
hydrolysis is more feasible