The wavenumbers and their attributions present in the infrared spectra of coconut oil and bio-oil samples obtained through the thermal and catalytic pyrolytic process.

Sample	Wavenumber (cm−1)	Assignment
Coconut oil	2920–2852	Stretching bond C–H
	1744	C O stretching
	1464	C–H bending
	1373	Symmetric vibrations of the CH3 group
	1157–1110	Vibrations of the C O bond
	722	Vibration of the long saturated carbon chain compounds
Bio-oils	1710	C–O stretching carboxylic acids, ketones
	1413	C–H strain vibrations
	934–1285	O–H stretching C–O(H) stretching (carboxylic acids, alcohols, aldehydes or esters)
	2360	C O stretching (CO2)