3.2.2. Aminolysis Reaction

Aminolysis reactions of a variety of feedstock (viz. WSO, AF, VSO, KO, and JO), FAMEs derived from them, and methyl laurate (ML) with varying molar concentrations of diethanolamine and catalyst amounts were performed at 90◦ C. All reactions were carried out until the completion of the reaction by varying one parameter at a time in order to establish the reaction conditions required for complete aminolysis in the minimum possible time. The amide derivative produced during the aminolysis reaction was characterized by FTIR and proton NMR and quantified by FTIR spectroscopy. The amide

derivative of methyl laurate was additionally analyzed using a mass spectroscopic technique. FAMEs prepared through the transesterification of a variety of vegetable oils and mutton fat were characterized and quantified by proton NMR spectroscopy.

Fatty acid amide derivative of WSO: yield > 99%. FTIR (cm−1): 3406 (νOH), 1617 (<sup>ν</sup>C=O); 1H-NMR (CDCl3, δ ppm): 5.3 (m, -CH=CH-), 3.77 (m, -CH2OH), 3.46 (m, -NCH2-), 2.7 (m, -CH=CH-CH2-CH=CH-), 2.31 (m, -CH2-CO-), 2.0 (m, -CH2-(CH2)n-CH-), 1.6-1.25 (m, -(CH2)n- ), 0.95 (m, -CH=CH-CH3), 0.87 (m, -CH2-CH3).

Fatty acid amide derivative of fatty acid methyl ester of WSO: yield > 99%. FTIR (cm−1): 3406 (νOH), 1617 (<sup>ν</sup>C=O); 1H-NMR (CDCl3, δ ppm): 5.3 (m, -CH=CH-), 3.78 (m, -CH2OH), 3.48 (m, -NCH2-), 2.7 (m, -CH=CH-CH2-CH=CH-), 2.3 (m, -CH2-CO-), 2.0 (m, -CH2-(CH2)n-), 1.6-1.25 (m, -(CH2)n- ), 0.95 (m, -CH=CH-CH3), 0.87 (m, -CH2-CH3).

Fatty acid amide derivative of animal fat: yield > 99%. FTIR (cm−1): 3406 (νOH), 1617 (<sup>ν</sup>C=O); 1H-NMR (CDCl3, δ ppm): 5.34 (m, -CH=CH-), 3.77 (m, -CH2OH), 3.46 (m, -NCH2-), 2.3 (m, -CH2-CO-), 2.0 (m, -CH2-(CH2)n-), 1.6-1.25 (m, -(CH2)n- ), 0.87 (m, -CH2-CH3).

Fatty acid amide derivative of fatty acid methyl ester of animal fat: yield > 99%. FTIR (cm−1): 3406 (νOH), 1617 (<sup>ν</sup>C=O); 1H-NMR (CDCl3, δ ppm): 5.3 (m, -CH=CH-), 3.75 (m, -CH2OH), 3.47 (m, -NCH2-), 2.3 (m, -CH2-CO-), 2.0 (m, -CH2-(CH2)n-), 1.6-1.25 (m, -(CH2)n- ), 0.87 (m, -CH2-CH3).

Fatty acid amide derivative of Karanja oil: yield > 99%. FTIR (cm−1): 3406 (νOH), 1617 (<sup>ν</sup>C=O); 1H-NMR (CDCl3, δ ppm): 5.3 (m, -CH=CH-), 3.77 (m, -CH2OH), 3.46 (m, -NCH2-), 2.7 (m, -CH=CH-CH2-CH=CH-), 2.31 (m, -CH2-CO-), 2.0 (m, -CH2-(CH2)n-CH-), 1.6-1.25 (m, -(CH2)n- ), 0.95 (m, -CH=CH-CH3)0.87 (m, -CH2-CH3).

Fatty acid amide derivative of fatty acid methyl ester of Karanja oil: yield > 99%. FTIR (cm−1): 3406 (νOH), 1617 (<sup>ν</sup>C=O); 1H-NMR (CDCl3, δ ppm): 5.3 (m, -CH=CH-), 3.78 (m, -CH2OH), 3.48 (m, -NCH2-), 2.7 (m, -CH=CH-CH2-CH=CH-), 2.3 (m, -CH2-CO-), 2.0 (m, -CH2-(CH2)n-), 1.6-1.25 (m, -(CH2)n- ), 0.95 (m, -CH=CH-CH3), 0.87 (m, -CH2-CH3).

Fatty acid amide derivative of jatropha oil: yield > 99%. FTIR (cm−1): 3406 (νOH), 1617 (<sup>ν</sup>C=O); 1H-NMR (CDCl3, δ ppm): 5.3 (m, -CH=CH-), 3.77 (m, -CH2OH), 3.46 (m, -NCH2-), 2.7 (m, -CH=CH-CH2-CH=CH-), 2.31 (m, -CH2-CO-), 2.0 (m, -CH2-(CH2)n-CH-), 1.6-1.25 (m, -(CH2)n- ), 0.95 (m, -CH=CH-CH3)0.87 (m, -CH2-CH3).

Fatty acid amide derivative of fatty acid methyl ester of jatropha oil: yield > 99%. FTIR (cm−1): 3406 (νOH), 1617 (<sup>ν</sup>C=O); 1H-NMR (CDCl3, δ ppm): 5.3 (m, -CH=CH-), 3.78 (m, -CH2OH), 3.48 (m, -NCH2-), 2.7 (m, -CH=CH-CH2-CH=CH-), 2.3 (m, -CH2-CO-), 2.0 (m, -CH2-(CH2)n-), 1.6-1.25 (m, -(CH2)n- ), 0.95 (m, -CH=CH-CH3), 0.87 (m, -CH2-CH3).

Fatty acid amide derivative of methyl laurate: yield > 99%. FTIR (cm−1): 3406 (νOH), 1617 (<sup>ν</sup>amide-C=O); 1H-NMR (CDCl3, δ ppm): 3.8 (m, -CH2OH), 3.5 (m, -NCH2-), 2.3 (m, -CH2-CO-), 1.6-1.25 (m, -(CH2)n- ), 0.87 (m, -CH2-CH3); EI-MS (electron ionization mass spectrometer) (*m*/*z*) (intensity (%), fragment): 287.2 (3, M), 270.3 (100, M-H2O), 227.22 (10, M-CH3(CH2)3), 175.2 (10, M-CH3(CH2)7), 132.2 (12, M-CH3(CH2)10), 114.2 (5, M-CH3(CH2)10OH).

#### 3.2.3. Synthesis of Fatty Acid Methyl Esters

In order to yield FAMEs for aminolysis, the same catalyst was also utilized for the transesterification of a variety of triglycerides (waste cotton seed oil, jatropha oil, and animal fat) with methanol, as shown in Scheme 2. All transesterification reactions were carried out in a refluxing unit consisting of a two-necked round-bottom flask (100 mL) fitted with a water-cooled condenser, an oil bath, and a magnetic stirrer. In a typical transesterification process, vegetable oil or animal fat (triglyceride) was mixed with methanol (in a 9:1 molar ratio with respect to triglyceride) with 5 wt % of Zn/CaO and heated at 65 ◦C until the completion of the reaction.

The catalyst was removed from the reaction mixture by centrifugation (at 8000 rpm) after the completion of the reaction, the rotary evaporated was used to recover the excess methanol, and then everything was kept in a separate funnel for 12 h to separate the FAMEs from the glycerol. The FAMEs

were thus obtained, further analyzed, and quantified through methods reported in the literature [32] using 1H-NMR data.

The FAMEs were synthesized through the transesterification of a variety of triglycerides with methanol (9:1 methanol/oil molar ratio) by using 5 wt % of the same catalyst at 65 ◦C (Scheme 2).

**Scheme 2.** Transesterification of triglycerides using the 2-Zn/CaO-400 nanocatalyst.
