The removal of naphthenic acid from crude oil by the stringer method using a zinc oxide catalyst based on aluminum oxide

Most acids in petroleum are either naphthenic acids or fatty acids. Naphthenic acids are the primary contributor to the total acid number of the oil,۱ and they may causeserious corrosion to processing equipment as the temperature increases during oil refining.۲-٥ In addition, naphthenic acids may cause emulsification during therefining process, which makes it difficult to separate water from the oil and decreases the oil yield. The thermal stability of petroleum products may also be reduced due to the presence of naphthenic acids. Therefore, the removal of naphthenic acids from crude oils is necessary.٦-۷ The reaction equation of the esterification of naphthenic acids and the alcohols are shown below in Eq. (1).

Keywords:

Crude oil , Naphthenic acid , Esterification , Acid removal , Catalyst