Pour Point Depressant of Fuel Oil Using Non-ionic Surfactants

摘要

Paraffin wax deposition from fuel oil at low temperature is one of the serious and long-standing problems in petroleum industry. The addition of pour point depressants (PPD) has been proved to be an efficient way to inhibit wax deposition. The influence of PPD on wax precipitation at low temperature was investigated. A different ethoxylated nonionic surfactants were prepared by reacting natural fatty acids (myristic acid and palmitic acid) with polyethylene glycol of different molecular weight. The synthesized nonionic surfactants were confirmed by NMR and FTIR spectroscopy. The surface properties of the synthesized surfactants, including the critical micelle concentration, effectiveness (pCMC), maximum surface excess (Gamma(max)), and minimum surface area (A(min)) were determined. The efficiency of ethoxylated nonionic surfactants was evaluated as cloud and pour point depressant for fuel oil was discussed. The results indicate that C16E7 surfactant posse's good cloud and pour point depressing performance. The effect of additive type and compatibility additive with natural wax dispersant on the wax crystallization behavior at low (0 degrees C) was evaluated. Photomicrographs showed that wax morphology was greatly modified to fine dispersant crystal of compact size. Correlation between wax modification and pour point depression appear to be merely qualitative in such heterogeneous fuel systems.