Proton (s) | Functional group | Chemical shift, δ (ppm) | |
Oil | Biodiesel | ||
CH3-C | Terminal methyl group | 0.80 - 1.01 | 0.8 - 1.0 |
-(CH2)n- | Backbone CH2 | 1.20 - 1.41 | 1.22 - 1.42 |
-CH2CH2-COOH | β-methylene proton | 1.53 - 1.70 | 1.55 - 1.69 |
=CH-CH2- | α-methylene group to one double bond | 1.94 - 2.11 | 1.93 - 2.10 |
CH2COOR | α-methylene group to ester | 2.31 | 2.31 |
=CH-CH2-CH= | α-methylene group to two double bonds | 2.76 | 2.77 |
-COOCH3 | Methyl group of ester | - | 3.67 |
-CH2OCOR | Methylene group (C1 and C3) of glyceride | 4.09 - 4.34 | - |
-CHOCOR | Methinine proton at C2 of glyceride | 5.25 | - |
-CH=CH- | Olefeinic protons | 5.28 - 5.43 | 5.27 - 5.41 |