Removal of naphtenic acid from petroleum crude oil utilizing 2-methylimidazole liquid with the aid of Ca/AI2O3 and Ce/AI2O3 catalyst / Amier Khairan Shaidi

Naphthenic acid (NA) is a carboxylic acid derivative compound commonly found
in the petroleum erode oil. The presence of these compounds contributes to the
acidity of erode oils and is one of the major sources of corrosion in oil pipelines
and distillation units in erode oil refineries. Removing NA compounds from erode
oils is regarded as one of the most crucial processes in heavy oil upgrading. In
order to overcome this problem, catalytic deacidification method had been
developed and used to reduce the total acid number values in crude oil. In this
study, erode oil from Petronas Penapisan Melaka were investigated. The
parameters used in this study were different catalyst calcination temperatures,
catalyst loading, concentration reagent, reaction times and reaction temperature.
2-methylimidazole and ethanol was used as acid removal agent and monometallic
calcium and cerium doped with alumina as a catalyst. The results showed that
with the catalyst, the reduction of original TAN that was 2.43 mg KOH/g can be
reduced to lower than 1 mg KOH/g. Ca/Al2O3 with a calcination temperature of
900°C gave a better reduction than Ce/Al203 with a calcination temperature of
900°C with 83.54% of TAN reduction (2.43 to 0.4) for Ca/Al2O3 catalyst and
71.19% (2.43 to 0.7) for Ce/Al2O3 catalyst. The best catalyst underwent several
characterization methods such as X-Ray Diffraction Spectroscopy (XRD), Fourier
Transform Infrared Spectroscopy (FTIR) and Thermogravimetry Analysis (TGADTA)
for its physicochemical properties. It can be concluded that catalytic
deacidification method was efficient and effective in removing NA from the erode
oil thus lowering the TAN value less than 1 mg KOH/g.