For FT-IR spectrum of the natural support NBP, The peaks around 1639cm 1 are due to the C=C
stretching that can be attributed to the presence of aromatic or benzene rings in lignin. The vibrations
around 1450 1470cm 1 could be due to aliphatic and aromatic (C H) groups in the plane deformation
vibrations of methyl, methylene and methoxy groups. The bands in the range 1050 1450cm 1 can be
assigned to the C O stretching vibration of carboxylic acids and alcohols.