Document Type : Research Paper


1 M.S. Student, Chemical Engineering Department, Ilam University

2 Associate Professor, Chemical Engineering Department, Faculty of Engineering, Ilam University, Ilam, Iran


This study investigated the effect of ethylene-vinyl acetate (EVA) as an inhibitor on wax appearance temperature (WAT) of crude oil in the Iranian oil field using the differential scanning calorimetry (DSC) method. The effect of EVA on the morphology of crude oil wax crystals was examined by a system equipped with an ocular microscope. The EVA inhibitor has an outstanding performance in reducing the wax appearance temperature of crude oil and prevents the crystallization process and the connection of the growing wax crystals to form a network structure by adsorbing on them. Adding 800 ppm of the EVA inhibitor caused the most significant decrease in the WAT of crude oil at a rate of 26.13 °C and formed smaller crystals and weaker structures at this concentration. Therefore, 800 ppm of the EVA inhibitor was selected as the optimal value.


Main Subjects

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