The biodiesel products were analyzed by high-pressure
liquid chromatography (HPLC) using a Perkin-Elmer Series
200 LC-pump and a refractive index Series 200 detector
and controlled by a PC with a software package (PerkinElmer
Turbochrom Navigator). A Zorbax Eclipse XDB-C18
column (4.6 mm × 250 mm × 5m) was used and the mobile
phase was acetone/acetonitrile mixture (70:30 v/v) at a
flowrate of 0.7 ml/min. The biodiesel samples were diluted
with acetone (HPLC grade) and the injection volume was
20l.