Page 358 - Advances in Eco-Fuels for a Sustainable Environment

Physicochemical fuel properties and tribological behavior of aegle marmelos correa biodiesel 313

catalyst. Thereupon, water washing was done to remove glycerol, the catalyst, and
other impurities from the biodiesel. Finally, the biodiesel was gently heated in the
rotatory evaporator to evaporate water and methanol.

11.2.4 Nuclear magnetic resonance

A nuclear magnetic resonance instrument was employed to confirm the methyl ester
formation. Proton NMR analysis was performed using a 300MHz AVANCE II
(Bruker Biospin, Switzerland) equipped with a 5mm BBO probe (Bruker BioSpin,
Switzerland). The TMS and chloroform (CDCl 3 ) were used as the internal standard
and solvent, respectively. The experiment was carried out at 25°C using the standard
pulse sequence library of TopSpin and followed by processing of the data.

11.2.5 Gas chromatography

The chemical composition of biodiesel was identified by using gas chromatography
with FID, model Trace 1110 (Thermo Scientific). The separation was carried out in
a capillary column TR-FAME, which has a 60m length, 0.22mm inner diameter,
and 0.25μm of film thickness. Helium was used as the carrier gas, and the flow rate
was maintained at 1.5mL/min. The column temperature was programmed from
120–300°C at the rate of 10°C/min. The temperature of both injector and detector
was set at 250°C. The AMC biodiesel sample was mixed with hexane solvent in a ratio
of 1:10 and injected.

11.2.6 Fourier transform–Infrared spectroscopy

Fourier transform infrared spectroscopy (FTIR) was used to investigate the functional
groupsofbiodiesel.ABrukertensor27FT-IRspectrophotometer(Germany),equipped
withanattenuatedtotalreflectancecellthathasaZnSesinglecrystal,wasusedtoobtain
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the IR spectra (absorbance mode) in the region of 400–4000cm with 24 scans.

11.2.7 Determination of physicochemical properties

According to ASTM 6751 and EN 14214 standards, the physicochemical properties of
diesel, AMC oil, and biodiesel were determined. These properties include acid value,
saponification value, iodine value, calorific value, kinematic viscosity, density, cloud
point, pour point, flash point, fire point, carbon residue, and oxidative stability.

11.2.7.1 Acid value

The acid value of raw oil and biodiesel were measured as per the standard EN 14104
titration method. In this, 50mL of a mixture of ethanol and diethyl ether was taken in a
beaker, and 1g of sample was dissolved into it. Then, 2–3 drops of phenolphthalein
indicator were added to the mixture. Finally, the beaker solution was titrated against