Synthesis of Alkyl Oleates as Pour Point Depressants for Crude Oil

• Main Author: Muchtar, Ansori
• Format: Final Project
• Language: Indonesia
• Subjects: Kimia
• Online Access: https://digilib.itb.ac.id/gdl/view/34221
• Institution: Institut Teknologi Bandung

Crude oil that is released from the reservoir flows into the oil refinery through pipeline channel. Low ambient temperatures can result in deposition of wax especially from heavy crude oil on the surface of the pipe. The wax deposition may disrupt oil transportation process because it can increase the viscosity of the oil and reduce the effective diameter of the pipe slowing the speed of the fluid flow. This problem can be overcome by using pour point depressants. In this research, alkyl oleates as pour point depressant were synthesized through esterification of oleic acid and alcohols (methanol, ethanol, and propanol) with 1:3 mol ratio. The resulting product were extracted using a mixture of water and hexane in 3:1 molar ratio. Furthermore, the remaining hexane was evaporated using a rotary evaporator. The resulting product was washed with saturated NaHCO3 solution and the organic phase was dried using anhydrous Na2SO4. The resulting esters were characterized using Fourier Transform Infra Red (FTIR), Proton Nuclear Magnetic Resonance (1H-NMR), and Carbon- 13 Nuclear Magnetic Resonance (13C-NMR). FTIR results indicated the presence of ester carbonyl groups which showed vibration around 1740 cm-1 in the products compared with the pure oleic acid which showed carbonyl vibration of carboxylic acid at a wavenumber of 1713 cm-1. The results of 1H-NMR and 13C-NMR characterization showed that the alkyl oleates were successfully synthesized. The effectivity of alkyl oleates as pour point depressant, was tested on crude oil by varying the concentrations of alkyl oleates of 500- 10000 ppm. Study of the pour point depressant properties of the crude oil tests showed that the pour point of crude oil (blank) is 33 oC. In the case of methyl oleate, no reduction of pour point was observed. Optimal performance of pour point depressants was with a value of pour point of 30 oC obtained for 750 ppm of ethyl oleate and 500 ppm of propyl oleate respectively.