Removal of Fluorescein Dye from Aqueous Solutions Using Natural and Chemically Treated Pine Sawdust

Table 1

FT-IR peaks of the functional groups in NPS and SPS.

NPS, wavenumber (cm^−1)	SPS, wavenumber (cm^−1)	Frequency ranges (cm^−1)	Groups (bonds)	Functional groups
3423	3415	3500–3200	O–H stretching	Phenolic or alcoholic
2915	2900	<3000	Sp^3 C-H stretching	Alkane groups
1700	1690	1850–1600	C=O	Carbonyl group
1650	1650	1750–1600	C=C	Alkene groups
1450	1480	1500–1400	Sp^2 C-H bending	Alkene groups
1340	1340	<1400	Sp^3 C-H bending	Alkane groups
1250	1240	1300–1100	Sp^2 C-O	Ester
1050	1050	1100–1000	Sp^3 C–O	Alcohol
530	545	550–450	Sp^2 C–H bending	Aromatic