Zeolite Y, with a Si/Al ratio 3.1, was prepared using Iraqi kaolin and tested as a catalyst in the liquid-phase
esterification of oleic acid (a simulated free fatty acid frequently used as a model reaction for biodiesel
production). XRD confirmed the presence of the characteristic faujasite structure of zeolite Y, and further
analysis was conducted using BET adsorption, FTIR spectroscopy, XRF, DLS particle size and SEM. A range
of experimental conditions were employed to study the reaction; alcohol/oleic acid molar ratio, tem-
perature, and catalyst mass loading. The optimum conditions for the reaction were observed at 70 C,
5 wt% catalyst loading and 6:1 ethanol to oleic acid molar ratio. The oleic acid conversion using the
zeolite prepared from kaolin was 85% after 60 min, while the corresponding value for a commercial
sample of HY zeolite was 76%. Our findings show that low Si/Al ratio zeolite Y is a suitable catalyst for
esterification, which is in contrast to the widespread view of the unsuitability of zeolites, in general, for
such applications.